Fuel Injector Not Pulsing "Intentional Shut Down" an SD Premium video
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- čas přidán 22. 08. 2018
- This is a 2011 Honda Odyssey 3.5L with a cylinder #3 misfire.
This lecture is part of my Chapter 18 "Fuel Injector Testing" playlist on ScannerDanner Premium.
You can subscribe here for a 14 day free trial: www.scannerdanner.com/join-sc...
Video breakdown:
0:32 intentional shut-down of a fuel injector introductions
1:07 fault codes, cause of the misfire (bad spark plug)
2:04 misfire data on scan tool
3:53 under hood connections with the scope
5:11 first view of the fuel injector waveforms on the scope
6:00 zeroing the amp probe
6:28 electrical "noise" on the injector circuit with the key on
6:40 electrical diagram of all the components running on the fuel injector fuse
8:27 fuel injector current ramp patterns
9:20 review of direction taken to troubleshoot this misfire
11:04 "Zach's Subaru" with faulty injector driver video link www.scannerdanner.com/scanner...
12:20 open fuel injector discussion
12:48 second mention of the Subaru video
13:50 how to sync an injector waveform
17:00 open circuit diagnostic testing procedures
21:16 intentional shut-down can look like a bad computer driver
23:24 initial start-up is critical (intentional shut-down strategy)
25:05 view of the initial start up and drop-out of the injector pattern
28:00 detailed analysis is not possible for where we took our measurement
30:00 what output circuits react this way (intentional shut-down)
Related videos:
SD Premium Chapter 18 "Fuel Injector Testing" playlist
www.scannerdanner.com/scanner...
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdanner.com/join-sc... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC. - Auta a dopravní prostředky
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Anyone who is a subscriber to this channel but is not on SD Premium is missing out on more than they expect. SD Premium is worth 10x the fee. Hell, I dont even really watch youtube anymore but I still subscribe to the premium purely as minimal payback for the extensive education Paul has provided over the years.
Learning diagnostics but not subscribing to SD Premium is analagous to learning to be a card dealer but never going to a casino. You will think you're prepared but will quickly find your skills are way below requirement in the real world.
Thank you so much Matt!
So which ones premium content is better? ScannerDanners or yours? :D
Thanks boss, I subscribed to you once but the series needed more content after the third month. I will sub to Danner and check it out. Thanks for the extra push.
This channel is a technicians dream and i would be lost without it
@@AveClubSound SD is the king. Math, he is excellent, he knows the things
When you are not a mechanic, know very little about cars... And yet you understand every bit of this video.... It's because the explanation was neat and perfect. That is what a good instructor does. Thanks Paul.
chungaleta1234 it’s true, paul is extremely gifted when it comes to transferring his knowledge to others. 👍
This is what I strive for. To make it easy to understand. Thank you so much!
Always got my back, don't you my friend? Thank you Steve!
Always Paul.
@@ScannerDanner I appreciate the reviews and how you get right to the point,,My sole purpose with schooling,,was repo,,shoot me now,,idc,,
Both tests the misfire counter stopped at 99, I think what Nic says totally makes sense. That's the limit, then the computer says shut down that injector. No reason to count after that. Great video, thanks for sharing!
This video reminds me years ago first watching SD in the classroom. Back then this wouldn't have made much sense to me. I guess I have learned a thing or two all these years later because it all makes total sense. Enjoyed the vid Paul, thanks.
Before finding your channel, I never knew an engine computer could kill an injector due to a misfire. Just that single piece of knowledge alone saved me countless hours of frustration, lost time, and money! I've learned a whole lot more than just that on the Premium Channel, though!!
Another AAA+++ vid, brother! 👍👍
it does make sense though if you have a injector firing with no spark your going to have severe cylinder wash or possable hydro lock maybe
I am an automotive college student and I have never watched an entire class on CZcams, this is the best instruction I have watched... ever. When you lifted the amp clamp up and then told your students how you zero'd it was subtle but awesome. Our teachers would fix it, and not mention how... which would make us puzzled when it was our time to play with the machine and tried zero'ing it without knowing how. You're awesome!!
ScannerDanner Premium subscribers will recognize this video. I am using this as a promotion to show others an example of the types of case studies and classes I am bringing to SD Premium. For those of you interested, there is a 14 day free trial which you can subscribe to here www.scannerdanner.com/join-scannerdanner-premium/subscribe-to/3-scannerdanner-premium.html
ScannerDanner i personally enjoyed the case study you did on a Lexus using a pressure transducer. Great stuff.
I just bought myself a 2000 series pico to learn to use it and get better at electrical diagnostics. I may join your premium channel to learn more like this. Although I work on heavy equipment, a lot of systems are similar.
You will not be disappointed. I have many heavy equipment guys using my material. Thank you! Hope to hear from you there.
Do you do many European vehicles
Excellent content Paul , Thank You Sir !
Der Mister Danner i must congratulate you on having this 2011 newer Honda vehicle on your channel . Newer vehicle's are what most auto techs see these days . Please keep up the great work and thank you .
Had this happen today w/a stepdaughter's car. melted igniter coil that also broke. I suspected it had purposefully shut down the fuel injector, but didn't want to have her drive it until I could confirm. I went home to check (happier using my computer to search, and phone kept dying), and she had called a tow truck before I could tell her to drive it to my house. Having destroyed 2 cats with a bad (brand new, non-OEM) distributor cover on a 99 suburban, I'm GLAD this feature is in new cars. Thanks for confirming this on the exact same engine I was working on.
In real estate it's location, location, location. In repairing cars it's diagnosis, diagnosis, diagnosis. Professor Paul the diagnostic master. Nice.
Gotta love this guys teaching . Can’t say enough great things about your vids dude. You teach me so much . Thank you 👍🏻
Thank you Mr. Paul, that was really a fascinating demonstration that I hadn't known about. You are my dream instructor.
God bless
I’m a professional tech for 15 years know shortcuts but my mind was blown with this!!!!! I’m a new subscriber but we can never stop learning. Keep doing what your doing you are helping all of us in the shops keeping our customers on the road much appreciated for the knowledge. Feel back in school again
thanks so much wayne!
@scannerdanner I just wanted to thank you for your knowledge and class here. I purchased your book. So my vehicle 04 corolla had the p0301 cylinder misfire #1. I started being a parts changer starting with coil packs spark plugs fuel injectors...was stumped...took my car to the toyota dealership and they tried to sell me a 4,000 head gasket job that would have been a waste of time...would still have the issue. I'm glad i had my car towed back home..then I saw your video... I tested the fuel injector wiring as youve shown using a noid light and found no pulse on injector 1. The wire had an open ground where the banks tie together. If I had not seen your video I would have continued changing parts. I am eternally greatful for your knowledge! Thank you!
Excellent video Paul. Really like the new format. Nice info to know on my 3.5 Hondas. First time IV heard anyone mention it . Thanks 👍👍👍❤️
Thanks Paul that’s new to me after all these years of automotive fixing experience
excellent video Mr Danner. thank you for sharing your knowledge. God bless you every day
I do a lot of work on BMW and I ran into one that had an injector leak while the engine was off so buddy went away for a week and when he returned try to start it no go it wouldn’t even turn it hydro lock the engine long story short the car was going to scrap yard for “SEIZED” Engine missed diagnosed I like your videos you go all the way to the root I love it great work!
Thank you Paul. Good job brother. I appreciate your videos. Have a good weekend.
You can deny it if you want to but i think you are a genius when it comes to car diagnosis. you make diagnosis look simple. thanks for making the Automotive industry migrate from old school to new school. keep the fire of greatness burning. God bless you.
Thanks so much man
Love to watch this guy specially when he is explaining I wish I take few classes with u
Thanks for sharing this .guys like you that can explain complicated issues with out ego .
Glad you enjoyed it. Thank you!
Really great explanation and vid, Mr. Danner. That has to be the coolest "whiteboard" I've ever seen!
Agree!
Amazing demonstration. Thank you.
Thank you for sharing, professor.
Awesome case study Paul. I enjoy all of your posts. One of the things I picked up on is it seems that after 99 misfires when the counter stopped counting on the scanner is when the computer turned off the driver. 99 misfires must be the criteria for turning the injector driver off.
Perfect video literally. There is no perfect in this world I know but this is the farthest as diagnostics video can go in quality in all aspects. That is the case with all of your videos.
I'm sure there are diagnosticians as good as you are, but for transfering that knowledge, there is no match to your videos.
Greetings from Serbia.
Wow thank you from Serbia!!
Wow this can save a customer too much money this infos are very valuable thanks paul
Thank you for sharing this kind of knowledge to us :)
the best instructor ever
This is a great lesson to be teaching those lucky students. I had a Nissan 3.3L (VG33E) one time that kept shutting off random/different injectors. I knew enough to know that the ECM was "doing it", but couldn't get diag time to figure out why. Cust had already thrown plugs, wires and dist. at it, and was out of money. (as usual...grrrr). Anyway, I watch your vids to keep sharp, those kids are so lucky!
i reacon your getting quicker paul cheers mate !!
So I can see this happening to if you took your volt meter and tested to see if voltage was present back pinned at the pcm connector for that control wire and all you saw was 0 volts . I would then try to disconnect that connector with the key off with my meter still hooked up and then turn the key back on and see if battery voltage becomes present. This will either verify if theres an open with that injector circuit or a short to ground in the driver itself. This will also help determining if you need too take the intake off or not. I do say I definitely love watching your videos cause you physically show how too not over think things and use the basic steps to set your self in the right direction when is comes to diagnosing any problem. Keep up the good work !!!! Your an awesome teacher and I would have loved to have had you as an instructor back when I went to school !!!!!
I would add one word of caution to this. When you disconnect the PCM, you may be losing power feed to the injector circuit which will add a variable to your voltage check. Make sense? This is why I use a test light connected to B+ for this test you are describing. To eliminate that variable.
@@ScannerDanner very true. I just looked up the diagram and the pcm does control the main relay which then my method I posted wouldn't really work by disconnecting the pcm connector. So then the test light would be the best option for that scenario i listed ( with the pcm still connected)
It was still a great thought process and test, it just has a variable is all. Nice job man.
PRODIGY Sir ScannerDanner
Thank you 👍
Take care and have a great day
Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧
it's always a good idea to start by looking at "ignition" components when there's misfires, before jumping to conclusions. perhaps I'm just old school, but it works for me 99% of the time :))
exactly what we did, thanks!
Not a car guy. Whatever is under the hood all look like a maze to me. But somehow, I was able to follow along and sometimes predict the next diagnostic action before SD reveals the next step. I think it's because ScannerDanner is a great teacher who guides us with a clear, logical, problem-solving mindset. Doubt if I'll ever put this knowledge to use but really enjoyed the lesson. Thanks!
Awesome!
After a hard days work it's nice to have a danner vid . SaaWeeet
Very nice video! Mice do like to get under those intake manifolds. First thing I look for in a miss on a V6 Honda is a nest.
Nice classes S.D.
u done it again u the man Paul 👍
Thanks for share this class Paul, Regards =)
this is education... great video!
thank you so much Paul !!!
Very nice video thank you.
That was a great lesson.
COMO SEMPRE... OUTRO VÍDEO EXCELENTE. PARABÉNS
Aleksi
Hi, I have a Chrysler neon 2001 with a remote problem. The times are working well and some times do not work and I have checked the coel does not send electricity to the candles
Great Video Paul. So for those of us without a amp clamp for our scope, could we just go to the misfiring cylinder driver wire at the pcm and scope the voltage while running see it at 14V. Then at startup we should see the driver pull it to ground till it shuts it down. In a vehicle this new the computer should be good at identifying which cylinder is misfiring from the misfire data or the P030x code.
As a guy that does this on the side I don't buy tools until I have to have them for a specific job, but I am really thinking about one of those clamps for my scope, and I really need a better scope too.
Sure, you can watch voltage waveforms and make the same determination, but it is certainly not as easy as pulling a fuse and reading waveforms from the fuse box. You can get an inductive low amp probe from my friends at AES for less than $100 and it will work just as well as my Snap-on an Pico ones will. I actually have this listed on my tools page of my website. Hope that helps
I have a 92 4 cyl Camry w 450k miles that I've owned over 15 years. Twice I had misfires and the car immediately overheated and had great loss of power. On one night, the cat was glowing red and the other (day) time oil was smoking off the second cat under the car. I think the computer has limited brain (what was avail in those days) and kept the injector squirting even though the plug was fouled. The ox sensors told the computer it was running rich so it probably cut back on fuel. With the continued misfire, no amount of leaning would bring the ratio into norm so it continued to lean it more... Hence the overheating. Both times I changed the plugs and it ran perfectly afterward. It would be nice if the programming logic was released to techs. I barely discovered and have subbed your channel. My thanks to you for such great detail and the explanation of the waveforms on the scopes.
Thank you!
Lucky to see your video as First nice video I learn lot from you image my life
Great Video on an off-the-wall occurence that would have you pulling your hair out and replacing many components. Thanks and Keep up the great work
yes true i seen this in some cars where miss fire could cause the car to shutdown engines thanks man brilliant work
I understand you were trying to point out how the pcm shutting down the injector can cause misdirection and/ or a misdiagnosis but I was doing the same thing your students were arguing with you through this video because they knew what was wrong. The most recent thing that taught me this lesson was a buddies clk430 that sat up because his wife lost the key. Misfire codes on a couple cylinders but focused on 1, confirmed spark with a test light then went straight for the injector. Watched the computer try to spray the injector for about 5 seconds from startup then stopped leaving me with WOW that's an aggressive strategy. Balance test confirmed a completely clogged injector. I don't own any snapon scanners but even the elcheapo elm327 with scanmaster software shows the upper limits of mode 6 stuff could you check to see if the misfire counter has a 99 count as it's upper limit. Thanks for another great video and your awesome channels.
And may you can know if you have a bad ecm or intentional shut off by disconnected cam shaft poison sensor in some cars.
One day I was working in Sentafe 2007 3.3L with P0341. And I have a cylinder 3 misfire but I don't have a code or intentional shut off for the injector, when I replace cam shaft poison sensor, the new code occur which is P0303 and intentional shut off for injector 3, and the problem was clogged injector 3.
just shut the engine off and restart it to determine intentional shut-down or not
Nice job 👍👍👍👍👍
I understand that the PCM is shutting off the injector for the misfiring cylinder to protect the Cat.
I would also say that if the injector were to continue to operate, you'd get cylinder wash down from the raw gas, also.
Thanks Paul Danner
Thank you Jesus
Thanks!
Is it possible for the injector driver on a GM 6.0l vortec to shut my #6 injector down even on start up? Because, when I turn truck off i can never get the noid to light or pulse at all. Feed/ control are both reading proper voltage KEY ON ENGINE OFF AND KEY ON ENGINE ON. I’m getting 14.2 at the ECU on the ground controlled negative KOEO... but noid light won’t light up... my dash went out last month and I’m only getting flashing blue needles, related??? I don’t know 🤷🏻♂️
This is a common issue with the J35 engine it happens to the Pilots and others also. Honda has a TSB campaign for the Odyssey for piston ring replacement.
Haven't received anything from you in a while...send them. Great class
Did you sign up for my email list? www.scannerdanner.com/scannerdanner-premium/scannerdanner-premium-email.html
This will enable you to know when I upload new content on SD Premium.
Great information thanks you!!!!!!!!!!
What a crafty computer.. lol. Clever these Japanese! Great video, more food for thought.
Hi Paul. Do you have any case studies diagnosis regarding on diesel CRDI fuel injectors? Thank you for awesome videos
I have a friend producing some diesel content on SD Premium for us. Here is my current playlist:
"Diesel Engine/Powertrain Diagnostics"
NOX Sensor or DEF Injector Leak?
2015 Mercedes Sprinter DEF System Problems
2017 Ford F-350 Superduty 6.7 Nox Sensor:module Testing (P020ee)
2013 F-550 6.7 Powerstroke - Variable Geometry Turbo Diagnosis
Really? 8 Bad Glow Plugs?
2015 6.7 Powerstroke EGT Blues
2014 F-450 6.7L Powerstroke, Reductant Heater Circuit Fault
I'm sure down the road we can get some material up on the system you're referring to.
www.scannerdanner.com/join-scannerdanner-premium.html
Awesome content. I'd be curious to see if the misfire counter stopped at the same time the intentional shutdown occurred. That would prove the other gentleman's theory. Additionally, is that the same point "Misfire Cyl4" went from "no" to "yes" (3:00 in the video, left side)? Again, thank you for sharing you knowledge.
Dan, the reason the misfire counter stopped is likely due to the fact that the ECM disabled the injector. When that occurs the ECM knows it is causing a misfire and doesn't report it. You probably already figure it out, but just in case.
Thank you. This issue is the same in the renault symbol
Great video once again! So if a bad spark plug caused the injector to shut down ( think I heard correctly) . Would the engine be running lean?
nice video thanks
I have a 92 Suzuki Samurai with EFI using a throttle body. Everything runs perfect. Then I add an MSD 6a 6200. I connected the two "+ & -" wires to the MSD input wires, and the MSD output wires onto the coil as shown on the MSD diagram. Also the MSD battery connection. Then tried to start engine. Engine starts and runs, but only if I continually pump the gas. Also, the check engine light stays on and the tachometer stoped working. I'm assuming that there is a missing electrical pulse to the computer, that the MSD is blocking or not providing. Have you got experience with adding an MSD box to this type of system? Or any advice on where I can possibly get help.
Thanks
Change it back to stock. That MSD ignition system will do NOTHING for your engine. Only a heavily modified engine with very high compression ratios or if you added a supercharger or turbocharged it, would you need the additional energy for the plugs to fire properly. That's what that MSD system is for. On a stock engine, all you'll do is wear out your spark plug sooner.
friend has a honda civic with acura tsx engine and we found number 2 injector had no control,turned out to be a cop coil caused ecu to shut down injector to prevent hydro lock but we came too close to replacing the ecu after seeing no control at pcm.by chance we found it was the cop not firing and another friend who was into these honda builds had brought up the ecu shuts down injector control when severe misfires happen on cylinder
Whats up scanner danner, Was wondering if you kindly help me out or point me the direction on my 2010 ram 1500 5.7l . Been getting p0300 random misfire. Cylinders 4 and 6 voltage drops in a couple seconds like your video. I ordered new ecm did the same, order another just in case first ecm was bad. Still the same, changed spark plugs, getting rich codes now on bank 1-2 . Changed intake temperature sensor/maf , crank/cam shaft sensors. Still throughing too much fuel i can smell in tail pipe. Any suggestions or thoughts brotha
Compression test should be next
Forgive me if you have already done this (I didn’t find it), but is there a chance that you could post a video covering the diagnostic equipment that you use? You won’t offend me if you go into great detail about each tool, but I would also be satisfied with a basic list of the fancy stuff beyond a test light and meter. I currently do not have a way of viewing waveforms and think that is the next step in my education. Just not sure which direction I should go. My laptop is ancient and I doubt I will keep a bench top oscilloscope around when I need it. I think I want something with more precise viewing than a handheld fluke scope would offer and the most limiting factor is that I am a cheapskate with high-dollar taste. :D
In GM's , this condition is accompanied by the cooling fan commanded on by ECU as well .
Brilliant
SO IN THE INJECTOR CONTROL CABLE AND THE CORRESPONDING CONTACT IN THE ECM WHEN IT IS IDLING WE SHOULD SEE 14 VOLTS IN ALL CARS?
More good stuff
I have a 1999 Chevy suburban that I just replaced the spider injector but still not running. The vehicle will run if I put gas in the throttle body. Any suggestions would be appreciated.
What is your fuel pressure. It has a service port, buy a gauge and test it. You can get one for like $30 for that set up
What can be the cause on a cummins 5.9 engine if it has all injector fault codes and check engine light on and the engine cranks but wont start
ALRIGHT COOL THANK YOU 👍 👍
Completely random, but I wonder how hard/easy was it for you to be able to set up the Verus to be controlled by the Smartboad? I think its nifty, and good info as always.
Paul where would we find that info. While doing troubleshooting. Is it referenced somewhere? How would we know? 👍
now you do :-), just remember this moving forward
toyota done it for the long time, if the igf cant igt for 8-10 cycles , pcm will shut down the injector, great infors for the misfire data and the intentional shut down on the honda, 1 quick questions, sir.
since all the new car will shut down the injector if theres misfire. so we cant really look at the fuel trim to determine the problems?
I have had that happen lol it will kill injectors
Just for my clarification Paul (20:13), if there is 0v at the PCM side I understand it could be an open circuit. But on the other hand if a driver turns on wouldn't 14v drops to 0v as well? Or we are looking at constant voltage change on and off (14v to 0v)? If we see 14v and then 0v that tells us a driver is working, correct?
Yes 0v could be an energized circuit all the time but here is the difference.
1. The amperage waveform we saw would be riding over top of a constant 1 amp baseline (we had 0v for a base)
2. The exhaust would be billowing white smoke from a constant spraying injector.
Hope that makes sense. Im just going from memory on this one
@@ScannerDanner Thank you, yes it makes sense. As always appreciate you taking time out and answering questions.
Iam going through the same thing with my 2011 honda odyssey...with number 4 injector misfire...changed the injector, plug the coils...the computer is still shutting down the injector...help please..thanks bro ..I have your book..could not find it in there...thanks
So it fires on start up? Do a compression test next on the number 4 and compare to another cylinder, preferably on the opposite bank but not necessarily needed, depending on the results. Pick an easy cyl to compare to first.
Thanks for the info Paul I learned something new. I really didn't know that later cars has the advance pcms to shut off injectors to protect the cat.. do all manufacturers do that now?
If so what years did they start doing that, if you know
96 and newer OBDII vehicles and not all of them react this way
Here in canada we have a service bulletin for cylinders 1,2,3, and 4 misfire due to carbon on the spark plugs from excessive oil burning on the v6 VCM motors. to correct the issue we would have to remove 1,2,3, and 4 pistons and replace the oil control rings. i believe there is a warranty extension for this issue.
yes sir, thank you. For this lesson, I didn't care about what caused the plug to foul or of the oil burning issue
I have seen bad injector coils(shorted/low resistance) cause driver/ecm to heat up and not work, but that was back in the days of throttle body injection, which usually meant the whole car suddenly quit, let it cool and it would run again for a while, then eventually burn the ECM/driver permanently.
I suppose it's possible with today's setups, but likely very rare due to all the integrated circuits and compact surface mount parts.
the difference in identifying that condition would be to simply shut the car off and restart it
What if the misfire really is a fuel related misfire and is a bad injector or injector with a defective spray pattern would the PCM still disable the injector in the interest of preserving the cat_converter?
possibly, but the key in recognising this condition is what do the injectors do on initial start up?
in engineering school they introduced us to the Fourier Series.. ie any waveform can be generated by combining sine waves. I wonder if an electronics tech can build a circuit or program a filter to look at the base noise and completely take it out, leaving the sought after wave. Spy audio does the same thing to filter background noise for clandestine eavesdropping. I see your tool eliminated most of it but it would be nice to have a clean signal.
the problem here is this is NOT noise, it is actual current flowing to other circuits
@@ScannerDanner "noise" in this case is signal coming from other sources we are not interested in... Clarification of my term.
Can t you make a separate circuit for the injectors to get rid of the noise?
Awesome video, thanks for sharing. But I have a question- All OBD2 cars don't do this, right? Thanks.
That is correct, not all of them do this and there are also other variables too. The main take-away from this video is to just know that this can happen and to not let it affect your diagnosis. Thanks!
Thanks for answering my question, and keep making these awesome videos! I have learned so much from you.
I know this is off topic but I have been digging for a while and cant seem to find it.. I feel certain one of your videos I watched a few years back, you used a scrapped fuel tank pressure sensor as a pressure/pulse sensor for your scope. Can you please point me at that link.. Thank You for sharing your awesome work. Cheers
found it czcams.com/video/levTV3XM7sI/video.html
Thank you!
Off topic, but those other current spikes seem a little extreme. They're occuring fairly close together (at a high frequency of occurrence). I can't imagine a MAF doing that, or any of the other things you mentioned, except maybe the ECM itself. I guess it would have periods of high processor load on that time scale while calculating pulse width, ignition timing and fuel injector firing calculations, keeping a time correlation with the actual injector ramps. I'd be looking to track that down, just out of pure curiosity. I wish pico made a four channel scope for a decent price. I won't even go into my rant about their pricing on the "automotive" scopes and their of letting people use those software based features on their cheaper scopes. There is no technical reasons to restrict the automotive version of their pc software to a certain line of scopes.
One thing that gets me why did the plug have oil on it like you said then you switch the plugs misfire changed from 3 to 4? Also wish you would have showed o2 data. Coil with 14v is showing continuity threw coil of injector also you could check ohms on injector threw fuse an output of ecm. But simple data could diagnose this without scope.
Hey danner. How would you know that is not bad transistor turning off because of the heat
It comes back on immediately at start up
I have a 97 Buick LeSabre it cranks and then shut off can you help me
Not unless you can tell me what it's missing when it doesn't restart.
can you make video about how to test car sensors using test light ???
U cant ,get a meter are scope
Have you considered subtitling off mic questions from you students? Just in case we miss the question, in order to put your answers in context. Thanks as always.
I have been working on making sure you guys can hear my students questions and also repeating them for you guys as well. Believe it or not, this video is from 2016. The 2018 stuff I am recording now is really, really good. Multiple cameras and when a student asks a question, I switch to another mic. Thank you!
You can identify defective injector by measuring resistance of injector 3 to ecu wire connector. Maybe ECU was more accessible.
resistance measurements will only tell part of the story and in a lot of cases can be completely useless, just a word of caution.
When an ohmmeter reading shows "good" it can still be bad. When an ohmmeter reading shows "bad", only then can you rely on the ohmmeter.
I like to say "resistance checking is not pass or fail....it is fail, or do more tests" :-)
@@ScannerDanner Good to know. I've seen a lot of people solely reply on the ohm meter and see it often in flow charts.