Honda Element Part 3 You can't fix them all
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- čas přidán 8. 09. 2024
- I've given up on this old Honda. Its time for it to go back to it's owner. He's gonna take like it is and see if it ever sets a code or not.
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One thing I have learned about Honda and their use of wideband sensors...they use the downstream O2 narrow band sensor for fuel control. We often ignore the downstream sensor as just used to monitor the cat but on Hondas it is also used to supplement fuel control. I ran into an issue on an 08 Odyssey that was running lean. I changed both upstream wideband O2's which didn't help. I then changed both downstream O2's and the fuel trims came back to normal. So, the downstream sensor is definitely used for fuel control on Hondas.
I know Nissan does this maybe if this car comes back we will try some testing with that.
I’m pretty sure all manufacturers do this by now, but an instructor once told us Chrysler was the first to do this back in 96. When working on a Chrysler, you may have seen a pid when scrolling through data called “O2 goal voltage”. I might not be 100% on the theory, but this is what I remember: When the cat is new, it works it’s best at stoich. But as the cat ages, it gradually requires a different air/fuel ratio to operate at it’s best. As the computer learns that the converter is operating less efficiently over time, it changes the goal voltage, meaning it bases fuel strategy not at 14.7:1, but as required in order for the cat to work most efficiently. So of course, if you have a biased rich or lean rear O2 sensor, you can end up with the same issues as a bad front sensor.
@@autodiagyt Down stream should hover between .6 volts. Watching the O2 through all 3 episodes. I can see it was not behaving correctly. Probably had oil on it?
Awesome video series! I agree that incorrect injectors are a real possibility. These ~160HP Accord/Element/CRV K24's came from the factory with 270CC injectors while the ~200HP TSX K24 and the ~200HP K20's in the RSX-S and 8th gen Civic Si came with 310CC injectors. The 270CC and 310CC injectors are physically interchangeable and the ~15% difference in flow rate is darn close to the fuel trims you were seeing. Also, as tight as those exhaust valves were, a compression and leak down test would IMO be worth doing to ensure that the valves and seats weren't damaged from the insufficient clearance, which is always a possibility when the valve lash is that tight.
Great suggestion
I’d give it an oil change and an Italian tune up. Very cool informative series. Love learning from you and the YT teachers!
There is a little wiggle in the vacuum gauge, so a cyl is not contributing the same as the others. With the exh valves being tight, they probably have some damage & less than perfect sealing. Plus 200K miles, does not help. I would ship it, and see what happens.
Cant ship a car thata not fixed. And 14 long term isnt fixed. It really shouldnt exceed 5%. And if the short term isnt changing then an injector is dumping unmetered fuel will explain why its worse when cold
It uses the MAP sensor and the TPS to determine how much fuel to put in. The computer trims is based on how the exhaust looks. I would check to see if the throttle body needs cleaned, clean it do a PCM reset and relearn the idles. If the throttle body it holding open a little because it it dirty it is holding open the TPS sensor more.
I had cleaned the tb months ago it trying to fix the stalling issue.
Ivan@PHD had a video recently about throttle reset and idle relearn.
@@autodiagyt
Nice how you interact with your audience and confirm/rule out their dartboard guesses on what the cause is for the customer complaint.
I'm just a DIYer and this is out of my league, but learning why some shops have to charge a minimum of an hour diagnosis time
That's kinda why some newer techs also have to be comprehensive with all these computer controlled modules sensors and outputs
Hopefully, the customer will provide an update down the road.
You're one of the few technicians that I watch. Your a Master Tech keep up the good work
I agree the trims are still too high. Your total trim of 20% will eventually turn on the check engine light. Injectors definitely could be excessively fuelling, a resistance check might show something. Higher fuel pressure could cause this, a bad regulator or restricted fuel return line, bad fuel could even skew the trims. I believe even a slightly restricted exhaust could cause it also .. between watching Ivan,Eric O.,Paul Danner, Diagnose Dan and Bernie Thompson on ATS, I've learned a lot and learn more and more every day... These guys are awesome... I'm sure one of them has a video out that would explain things better..
MAP confounded me for months on my personal car. It was reporting false info. Took a chance and replaced it and it was the FIX !
Watched the Honda Element videos. The comments on the Map Sensor value is interesting. I know map values can affect fuel control. Not being sure if the sensor was accurate, I would have used a hand held vacuum pump to change the value a bit and see how the LTFT reacted. Just a thought .I don't really work on Honda much either, just from domestic experience. I like your approach to diagnostics and your videos.
That vaccume gauge connected to valve cover was flickering back and forth is telling you your valves are not sealing. With the fuel trims i would say intake valve is leaking and sucking raw gas back in intake being ingested by cylinders that are sealing
I had a Chevy with -20% fuel trim. Turns out they had premium fuel in there and it was working just fine. I also found out they have a PID for fuel volatility which read high volatility.
I would run a scope down each cyl first thing in the morning. If you see fuel, it's an injector. If you see oil then stem seals. You can also look at valves for carbon. I personally think you will find a bad valve seat from tight valves.
I worked on vehicles most of my life diagnosing is critical had a vehicle that would miss/jerk at 35 mph checked everything out it was a brand new vehicle with 1000 miles on the clock checked timing mixtures had a word with the top engineer explained to him what was happening he said did you check the valve clearances I said three times he asked what I set them to 8 thou inlet 12 thou exhaust he told me to reset them to 9 inlet and 13 exhaust road tested the vehicle all fixed I did not realise how critical an extra one thou would be keep up the good work peta
Just a thought, if the exhaust valve gap was too small, there is a strong possibility that the valve is burnt. It got burnt because it's dwell time against the valve seat (exhaust valve heatsinking) is too short.
Absolutely great videos. I am always looking forward to you posting new ones. Thank you
My thought too.
Great series and thanks for taking the time for sharing.
At this point I believe there are multiple factors causing the issue. The car has 200,000 miles and nothing is perfect and the combination of all the little things are contributing. New injectors might help, but the engine still has 200,000 miles on it.
My Honda was running rich without codes. I cleaned the throttle body and map sensor and it fixed it.
Thanks for sharing this case. In my opinion this type of cases are the most valuable, there is so much to learn and "enjoy", on one had that not all is 'roses all the time', and also the responses from the community to come up with possible things to look for.
Thanks for sharing. At 4:59, you have int and exh wave forms . the best way to verify for proper valve over lap or valve adjustment is engine cranking only cold and warm they looks different. I have even gotten data the has point me to carbon deposits on intake on GDI engines, engine running is not the best scenario since the engine espeed increases, idle control valve , engine load or rpm changes . Great diag there is always a vehicle is going to kick our but no matter what
You rock! .....oil change will make a difference, valves should be a tic loose..not ticking but a 'tic' on loose side of spec
We see at 3400 ft the value you see on the scan tool on the map. And that value is normal for us at 3,400 ft.. But I've never seen it that low with 21 inches of vacuum. I do feel your pain it's a tough deal.
On that Honda key on engine off in OBD2 what's the barometric pressure 26 28? corrected for your elevation. Our barometric pressure reads 26 at 3400 ft. Old school vacuum gauge do the math on it and see if it's in sync. 21 in of vacuum You must live on the beach. In the scheme of things I think I'd try an OEM map sensor first and if it don't fix it so what.
I’m at 1,000ft and it reads in psi and it’s pretty close to what my phone app shows. This was covered in the first video.
well at least it seems like the cold start is a fix nice . don’t you have a local place that will test those injectors , over here it’s not big bucks to have a set tested . but i guess the dealer don’t won’t to spend big money on a repair. eat into any profit one the car . have to say your a great inspiration my friend i have had nothing but can faults this week lucky i have been going through your videos over the last month so have been remembering things i had forgotten about can network and how to test ( getting old 🤣🤣🤣)
It’s more work to take them out and test them then it is to just replace them lol
@@autodiagyt slightly more expensive and if it’s a fail you gotta eat it 🤪🤪🤪 but i hear what your saying labour wise 👍
I'm still leaning towards too much EGR flow. The oxygen depleted exhaust gas is is mimicking a rich condition. O2 sensor is sensing less oxygen in the exhaust. The engine is then corrected to run lean but the EGR is masking the pre-ignition.
No egr on this engine. Egr is accomplished with vvt.
THANK YOU FOR the step by step diagnostic. As I can use this kind of information for Guidance and instructions on what to and NOT to do. Sorry you couldn't bill for all your time.
If there’s no misfire or stall you’ve done your job . If you would’ve done the valves right out the gate you probably wouldn’t even know about the imperfections. Your extensive diagnostics led you to something that wasn’t the customer complaint. They just want to be able to sell it. Now they can so good job👏
Wish I had half your understanding and capabilities in the diagnostics and tool department.
First, I’d probably try unplugging the rear o2, reset the trims and drive it. If the trim is still racking up, that would pretty much rule out a bad rear o2. If that turns up negative, I’d also like to see an injector waveform, as well as voltage being fed to the injectors for the hell of it.
I’ve seen a plugged cat cause a rich condition as well, (with an obvious drive ability issue which was the original complaint, not an engine light with a trim issue) but either way I’d like to see how it would react with the cat disconnected. You never said it lacked power, so probably not the issue though. Sorry, I didn’t watch all 3 videos start to finish, so maybe you already did some of these
Speed density highly relys on map at that low value i noticed the calculated load pid was 28 at ldle ,thats a little high for idle and could cause extra enrichment 🤷♂️
Hello. I had a Honda just like this with moderate (-) fuel trims and after checking the fuel pressure it was too high. turns out someone messed up doing the fuel pump and had the return line pinched.
Hopefully this video series does real good for the channel, cos i got a feeling your not billing for all the time you have into this honda.
No definitely not sadly.
MAYBE IT'S TIME FOR YOU TO ADD AN AUTOMOTIVE 5 GAS ANALYZER TO YOUR TEST EQUIPMENT LIST . JUST ONE QUESTION WITH THE ENGINE RUNNING HIGHER FUEL TRIMS WOULD THAT NOT SHORTEN THE LIFE OF THE CATALYTIC CONVERTER. THANK YOU FOR YOUR TIME AND LOOKING FORWARD TO THE NEXT DIAGNOSTIC !!!!!!!!!!!!!!!!!!!!!!!!!!!
With Pcv and evap disconnected short trim was normal at idle but whent negative -10 when u rev ..maybe has something to do oxygen sensors
My 2011 honda pilot has 178k miles on it.fuel trims still perfect
Kinda bummed the customer bailed on this one. Typical used car dealer behavior. I agree with some others. Change the oil. Check for over fueling pressure regulator. Thanks for the videos. Much to learn on this channel.
I've got a Ram right now that is a similar problem. Tota ft's -50%. All sensors reading correctly. Most importantly the MAP and O2's since it's speed density. Misfires on 1 and 4. Customer installed their own plugs. They were knock offs. We put new ones in it. No change. RC test showed cylinder 1,5 and 7 are lower. But not extraordinarily so. All injectors ohm tested equal. Between 12 and 14 ohms. Within spec. So I'm currently trying to think outside the box. Cuz it's got me a bit stumped.
Sounds like the customer installed some knockoff injectors as well.
@brycelund4112 We installed new injectors on cylinders 1 and 4 that are the ones counting up on the misfire monitors. No difference. And resisted tests shows all injectors are equal. Obviously that doesn't mean they're flowing the same. But that's where I'm headed next. Going to unplug just injector 1 and then 4 to see if my ft's clear up. If so those injectors are skewing the ft's for that whole bank. And would also mean the newly installed injectors are also shit. We'll see.
I know you said all sensors reading right but if your misfires and rich condition is on one bank, I would recheck the o2 sensor readings. Had a 12 ram that shop gave up on it doing pretty much everything they could to fix a rich & misfire codes. What I saw on o2 voltage made me do some tests and I discovered someone has connected the front o2 to the rear o2 plug and vice Versa. Connectors are the same and they were just hanging and not secured. After swapping the plugs and restarting the engine, It took a good 10 minutes for the engine to work right again. Still had some -14 trimming but the oil change fixed it. Good luck
I'm facied these issue before
Due to engine seized there is mixture going inside engine case after that going to intake manifold through PCV valve
Just remove the pipe between pcv valve and intake manifold after actuator and use a plug or anything else to block the suck fresh air from the pipe and check short fuel trim
You could have the fuel pressure too. One time someone put a Chinese Ebay fuel pump and the fuel pressure was much higher than normal, causing the injectors to spray more fuel than a base amount. That caused the PCM to trim down the fuel .I would also check the fuel pump pressure. And if someone put non-OEM injectors in. It could be a combination of the two. Remember, you only need one bad injector to ruin the whole bank trim.
I would do an oil change, throttlebody service, and Italian tuneup.. allow the valve to rotate making it seal correctly!
If it was wrong injectors prob would be setting a rich code . in my experience.. I had 240cc injectors instead of 190cc in an older civic ...
There are shops that can flow-test injectors. Obviously the injectors are all functioning, but might be partly fouled (dripping, not spraying).
The engine is not actually running rich. From your last video it was running at Lamda 1. Long term is a memory trim and can take time to re learn unless you do a fuel trim reset and start from there. I think your over thinking it.
I'm still going with #3 injector. The ecu is getting delayed information from the O2 so it throws a #4 misfire. The fuel trim isn't bad enough to be multiple injectors in my opinion.
The misfires have completely went away
Jake I seen Eric O solve a fuel trim problem because the vehicle ecm was stuck in E-85 mode the computer was adding more fuel thinking it was alcohol but the O2 sensors were seeing gas he did a reset in ecm somehow 🤔
I’ve reset the ecm several times.
@@autodiagyt
Be interesting to see if you run it on E-85 would the fuel trims be right 🤔
@@marcokahny709 if there was a e85 station close I might would try it lol. Closest one is 45 minute drive away.
@@autodiagyt
I know you're dying to know what would happen
You might be on to something there on the injectors? Sounds like the owner is good with it. Thanks for posting.
I'd try cleaning everything that can be cleaned. MAF, IAC, throttle body, change air filter. With that many miles, a good cleaning of all the sensors that can be cleaned wouldn't hurt a thing. Maybe if everything is dirty, they are each contributing to the problem but not to the degree that you can detect by testing. A can of cleaner is cheaper than injectors and may fix the issue. I like to rule out stuff like that before I go spending money. Great case study. Thank you for all your hard work making these videos.
MAP sensor is indirectly used to control Injectors instead of MAS , and i noticed the vacuum gauge is higher than normal engine ! means a restricted intake ! i might be wrong though.
Your intake pulse sensor trace at the 5 minute mark shows that you adjusted the valves correctly. The “M” at the top of the red trace is what I’m talking about. Particularly on #4 intake pulse.
Did you take a look at the IAT? If air density is misscalculated it might think that the engine is getting more air. Also unplugging o2 sensors and reading it with a standalone one line tuners use could help
Great video series and true conclusion! Yeah, not everything is fixable..
About fuel trim - maybe it's fuel rated issue and is ok with that type of fuel and can be solved by fueling in different station or with other octane fuel.. 😉
In my car, ECU by manual, can accept any type of gasoline and is self adjusting, but I never put in it nothing less than 95 and never looked at long term, short term live stream for my car..
Hi there , I’ve watched parts of ur videos because being busy my end I normally watch them all the way through, so I’m going to say something that you may have done so bare with me on this . On alldata it does say to do a throttle body relearn because the ecu is staying where it is regarding the rich condition. Apparently it takes some time to complete. Be great if you could comment back please .
Yes I’ve done the relearn several times. I just cleared codes and reset everything again today so that it’s ready for the customer to pick up and after the idle relearned it’s still back to -16% LT trim.
Pat on the back my friend... i am for you just like all who post those great comments~Keep up the awsume work and tedious filming and the great patience you have 😎👍
Check for exhaust leaks, especially near the o2 sensor
Awesome MAP check teaching!
Oh and engine vacuum is 18 inches of mercury. So it's healthy. And it agrees with scandata. Next is disconnect injectors 1 and 4 and see if ft's clear up. May have faulty cylinders and or injector flow is somehow incorrect. Either way at this point there are no obvious reasons for the rich condition.
What I once had seen fail was the variable valve adjustment aisin on a Renault mechanically first was wrong timing then fail after as Renault have no fix timing marks
Timing has been verified while running
the only thing left is the injectors and I've seen enough videos where it's usually 1 maybe 2 bad injectors that are adding a considerable amount of extra fuel causing the fuel trims to be out of wack.
Is that particular Honda have California emissions, or is it ULEV or SULEV? Being a density-charge type map system, the downstream O2's tend to affect drivability more than most other vehicles. But I think given the mileage on that one, you may have done all you can do, without pulse testing all the injectors and using a 5 gas analyzer.
Ok...would be a good Bernie Thompson case study! Get in touch. LOL
Your vacuum gauges is reading way higher than the map sensor. There is your problem.sometimes they get obstructed or the diaphragm leaking. Remove it and use a hand vacuum pump, pump at 20 and see if it matches the scan tool, also see if it holds the suction.
The mechanical gauge and map sensor do read the same. I'm pretty sure I explained it in the video that the map sensor is reading in absolute pressure and the mechanical gauge is reading gauge pressure.
@@autodiagyt your right, i checked my tsx and the higher the vacuum the lower the psi.mine also is around 4.9 at idle .
maybe a bad seal at the spark plug to block, this would let extra air come into the engine and make the computer think it was lean on that cylinder, then pull fuel away?
This kind of reminds me of my own Audi A5 2.0T 2015, but reversed. It's been running lean with LTFTs of +10-12 percent and it's been driving me mad, don't know what it is. Smoke test in air intake did not reveal air leak. No codes at all.
Could a valve seat(s) or valve(s) be damaged from from running tight for too long?
What was the rear 02 sensor showing? Some vehicles will help the PCM for decision of fuel injector on time.
Anyway, I like your decision about injectors later on.
To me the O2s are agreeing. Downstream seems to act and read how I'd expect.
I think the fuel trims won't even set a code until they get to 20% (I'm not certain on that).
I have seen several videos on aftermarket injectors being over sized and spraying too much fuel. I wish we had a known good injector balance test on this engine, to compare with your test; but I couldn't find one.. I think you're probably right: someone likely put in aftermarket injectors to get "more power baby" -- without a tune... and now it's just flooding everything. :) .. If it never gets any worse than - 10%, then it's fine, and shouldn't throw a code. But the problem is-- when you revved it and showed -10% short term on top of -10% long term.. That long term will eventually relearn and adjust to a -20% trim. But maybe it will never be driven long enough in that higher RPM for it to ever make that adjustment. Ship it
He would need a volume gauge ,or he could bypass to measure cup in a 15 second time to measure volume then multiple it to the min,or hr.
Sean Tipping sent me. You have great editing skills, great video series!
Awesome thanks did you listen to the podcast?
@@autodiagyt yes sir I did.
Seen used engine with all the wrong injectors cause trim issues .check the part numbers on them
blueskiesmobile4253 is right about an oil change . Could be some fuel in it that the ecm is seeing via the pcv .
I removed the pcv from the equation in the video and show it still had a negative trim.
Hey man, great video. Say, I might know the problem. In vehicles, there's this thing called a cold start injector, which injects more fuel into the engine when it's cold. Sometimes the little valve gets stuck, and it's common. You just gotta pay attention to it. If it restarts after stalling, then it's a cold fuel injector problem. If not, then it could be an intake head valve stuck closed, and it's "choking" the engine
_"In vehicles, there's this thing called a cold start injector, "_
Some early electronic fuel injected injected cars used an extra injector for enrichment (my 1992 Toyota MR2 Turbo did), but I've not seen an engine use this in a _very_ long time. Enrichment is now performed by the ECU injecting more fuel via the normal port or direct injectors.
Only a few things can make it rich alot of stuff can make it lean
change oil and clean throttle
Brake servo, Injector?.....11.6psi before starting and drops to 3.6psi after it's warmed up and running.
The map sensor readings are in the normal ranges and if it was out it would set code for it....net post.
Jake good morning. Have you tried an injector leak down test and compare the results of each injector? Maybe you have or I missed it but maybe comparing each inject would be helpful. Whatever it is seem to be affecting both the short term and the long term. Maybe they will say change them or it will live for another day. 👍
Yes they have been checked
@@autodiagyt thanks Jake 👍
I would agree with some of the people on here with the down stream 02 sensor. You can try and short the signal wire of the 02 sensor and see if the fuel trims change. You should be able to drive lean and rich my using positive and negative terminals. Juat use your body as reaistance so you dont short anything out. If you wet the tip of your finger it will pass current better. Ita a great cheap way to test 02 sensors.
Calculated load looks a little high. I would remove map, and make sure passage is not caboned up. I would disconnect evap purge line and pcv, and look at trims again. Blessings!!
I would not do injectors. I would also check exhaust backpressure.
All of that is covered in this video
psi * 2.02 =inHg for map, 17-22 inHg should be at idle. seems low. That would scew the fuel strategy.
So you think there is to much vacuum?
Small correction here 1 psi = 2 inHg , so that should be psi / 2 = inHg.
I also thought vacuum was too high. Is there timing adjustment on that model or is it computer controlled? My uncle once told me 18-20 inHg at idle.
Jake, my engine m276.820 on W212 E400, from MB is on purpose set at "slightly rich" as per its med177 ecm variant coding. LTFT commonly at -8 to -10%. While STFT depends on how agressive i drive, as WOT will give open loop lambda control., can be zero % at grandma style driving to -5% if lead footed.
Is there similiar honda propeitary data like i mentioned, if one can get honda oe scan tool .?
Worst case scenerio just get one and pop it in, it's better to waste one instead of four.
Hondas are very picky about valve adjustment
I have a couple questions. does it get worse with time like the cat is not flowing enough causing fuel trim issue. also does it have an egr that could be sticking causing a rich condition and what is the routing of egr for previous work. for example I had a guy do his own headgasket but put the egr mount gasket on backwards so it was constantly sucking exhaust even with egr blocked off.
No egr on this one. Incylinder doesn't show a back pressure issue either.
I wonder if the vtec valve is not shutting and running on the larger cam profile
Vtech is working correctly
A suggestion: It could be a crack at exhaust pipe before sensor. This should explain the rich thing... so the sensor measure oxygen and, like this, you'll have fake rich mixture with a fake air entrance. engine looks like pretty nice for it's mileage. For testing this suggestion, with engine not hot, to reduce risk of flame, you could use a wd40 or a brake cleaner spray to analyse if the oxygen sensor will have some perturbation.
test: spray it over the exhaust side, trying not leave admission get it, and take a look if the oxygen sensor have fluctuations at the measured values. the spray should indicate a very rich value for some moments, if there is a crack. It's like testing admission for fake air entry. Success always!!!
Note: The admission red waves are not exactly the same, one cylinder, before valve clearance correction, had a round shape at it's upper part.
By fake air entry, I mean air leak... 😅
- Check part numbers of injectors to see if they are the right ones for the car.
- Mass air flow sensor off
- O2 sensors off
- Exhaust leak near o2 sensor
- VVT off
Run some K44 through it!
Have you ever thought of looking at the calculated MAF in the ecm and measuring it with a diy maf sensor with arduino?
No I have not. Seems like alot of work to make it and implement it on different vehicles. I'm really not tech savvy at all and wouldn't even know where to start with an Arduino
When times get better for me, i am going to buy a bosch one and convert the Voltage to mass flow and display it on a small screen. Then just adapt it to the cars intake before the air filter.
Of course this will tell you only that it is flowing more/less air. This could be a bad MAF, MAP, IAT, Leakage, or a bad calculation since the engines VE (Volumetric Efficiency) changed from stock because of a damage like Valves, Timing …
All three videos, I recommended looking into the MAP being slightly skewed, like a dirty MAF.
There is no MAF on this engine and I showed the MAP in this video is accurate with a mechanical gauge reading
Intake metering is what's most likely causing the A/F sensor to see "rich". (I know it doesn't have a MAF, as I was using it for a comparison) Something on the intake side is skewed.
@@HouseCallAutoRepair if it is I’m not seeing it. To me it looks like it has a lot of vacuum and if it’s skewed it’s reading less then actual so that would put it lean on the AF sensor.
Amazing and maticulate diagnosis👍What about EGR valve leaking and diluting mixture? Just a thought man.
No egr on this engine
cool
If you can get a known good car and check that data against this one - may give you some other clues - valve adjustment is critical though - have seen correct valve adjustment result in a completely different running engine
burned valves, should have adjusted the valves sooner.
Check the (MAP) sensor voltage with either a scan tool or a volt meter.
Test at the Green/Red wire. Normal voltage is 2.8V to 2.9V (KOEO) and 0.85V to 0.90V at a hot idle (KOER).
Double check engine vacuum. If the MAP voltage is reading too high at idle, suspect tight valve adjustment (you did that).
With an oscilloscope, check the burn time (vertical lines with oscilloscope) at the secondary circuit, measuring all 4 spark plugs.
Check Spark Plug quality. Find out if there is a throttle body adaptation. Check oil quality.
1.0 to 2.0 ms is considered normal, anything wider is considered too long at idle.
Investigate fuel quality for ethanol.
Complete an OBD drive cycle and check again.
I would send a shout to Ericthecarguy. He used to be a Honda tech.
After a few completed drive cycles with no check engine light or code spending your good. Surprised you haven't had Vtec solenoid problems and stolen cats
The vtech solenoid has been replaced on it at some point. It looks really new
well if you had the data parameters you could check the injectors dwell time at a particular speed and calculate fuel flow to give you the a/f ratio and see if it matches what you are seeing and then figure what it ideally should be blah tee blah tee blah lol.
It’s all Bernie. I’m not that smart lol
After watching 3 parts and reading the comments. "5 gas analyzer" would be like a good way to test and confirm the front and REAR oxygen sensors . But i undertand you don't have one . Second(this is going to be a long one) - Since the fuel trims cuts more fuel when you load the engine or increase the RPM , i would be interested in scoping the secondary ignition under load or higher rpm. Because in Part 1 you only scoped it at idle. And FOR ME it was clearly showing the rich waveform. Because at the end of the burn line ON EACH CYL there was not enough "nose up" . But even worse , on number 4 cyl( video Part 1 - 16:04 ) you can see there's not even a tiny "nose up" at the end of burn line. And again on this same cyl 4 , the end oscillations are very little compared to other cylinders indicating either that the coil had to deliver nearly all of it's energy to try and burn the richer mix in cyl4 (and there's no energy left to "oscillate") . Or SECOND - the coil is SLIGHTLY weaker than the others. The "weaker coil" path could be eliminated by swapping the coils between 4 and any other of the three and checking the waveform again. If the same waveform is present on cyl4 with swapped coil from other cylinder i would go towards slightly leaking injector 4, only when engine is operating(since static injector leak down tested OK). I would then suggest the customer to buy only 1 brand new OEM injector and replace it on number 4 cylinder. Then again - secondary ignition waveform to compare the new injector to other cylinders. If there's differences between the new injector and the other 3, i would go for replacing the other 3 injectors since the high mileage. It's a nice test if one doesn't have injector test bench.
I forgot to film the secondaries again but after the valve adjustment they all matched each other. #4 didn’t stand out as being different. It was possibly just pushing a little bit of air out of the cylinder causing a slightly richer air fuel ratio.
Air filter clogged? Some rag is stuck in the air intake pathways? Feels like not enough air, and computer removes "extra" fuel.
Seems there's not much more you can do Jake, without starting to change parts to test.
Have you checked for excessive fuel pressure? If it's not an injector issue, excess fuel has got to come from somewhere 🙂
Engine running it maintains 52psi I didn’t see a spec for it on alldata but i possibly am not looking in the right place. But 50-55 is generally what I see on most returnless fuel port injection vehicles.
@@autodiagyt That leaves for partially leaky injectors, I guess.
What is the history of this car (it does not say in the description). When did it start doing this?
Auction car no known history
I was thinking high fuel pressure causing it but when u went to cruise speed the trims went more negative and car had power so exhaust wasnt the promblem and egr leaking maybe stretched timming chain ?
No egr on this engine and the timing I spot on with a known good waveform I found.
Were the valves tight as usual on Honda's?
Grasias
Hi, have you asked ericthecarguy? He's a Honda trained tech