Thanks Matt!! Nice and simple! As you may recall, I have this issue, sent my ECU back to Holley from Australia just to have them send it back saying no problem with it 😕 I can now add some compensation back around the idle rev range as I had to zero it out. Thanks mate!!!
Another quality video from Leech Motorsports. My car has the opposite problem, it stays at 9.6 AFR until the sensor heats up, it tries to idle but will usually die before the sensor is warmed up, if I keep my foot on the gas then it will stay running. After the sensor warms up and starts reading it idles. Looking forward to the next video.
@@stephenmaggard1280did you ever figure this issue out? I am having a very similar problem. Should cl comp be 0% in 1d table or more to allow it to actually pull more fuel away ?
I have this issue also. 9.6 afr with no change until 30 seconds in it want to die. Then the sensor will start reading and engine will even out. What was your solution to fixing this?
I have been chasing this exact issue since you tuned my car years back. I’ve learned a few things… but don’t know what to make of it. Holley warrantied my O2, no difference. I sent my computer to them, they said no problems. I think it’s 100% in the heating logic. I learned the following: if I go key on, engine off for that same 20 seconds… the problem won’t be there when I start the engine. If I watch the lights on the ECU the O2 light will be yellow, then turn green eventually. If I start after the green, no problem. It’s as if the heating circuit is lazy, not the sensor itself. Now here’s another odd thing… I went down the “maybe my starting voltage is low” line of thinking… replaced battery, re-did grounds (and added 3 more), changed to low amp draw starter… no change. During this time, I noticed that if I put my battery on a trickle charger for 15 minutes, the issue went away! I don’t have any draws and it’s always at full voltage after sitting for any extended periods. It also will seldom (very rare) display “heating” instead of “initiating” on the handheld after a long hot drive. Very rare, and very random. Anyways- don’t know why it took so long for me to find this video. Going to implement the change now. It’s a real bummer Holley doesn’t have a fix for this!
Working great after implementing. Over the past 2 years dealing with this- I noticed that the hotter the engine, the shorter the 35.6 hang time. I used a 2D table with time and CTS. Seems to be working great!
My Terminator has been doing this after driving for a while! Especially on the highway when I give it some gas to pass or something. GAH YOU ARE MY SAVIOR
The two most common reasons I hear for this happening is Holley EFI has a shit heater control strategy, and sensor placement. Most guys, myself included, just stuck it into an old narrow band bung on the header collector. Which sits at about 3 or 9 o'clock on the pipe. Ideally a wideband wants to be at 2 or 10 o'clock. Something about moisture running out of the sensor at 2 or 10, that just sits there at 3 or 9.
do you have a log you can show of this scenario? i'm just wondering if the ECT sensor is in an air pocket or something? i can't imagine the o2 is causing this problem?? but whatever the cause, good fix! almost like OEM.. :)
I will have to do a log and see if I can see this, I have never noticed it on mine. I do have the fuel pump prime set on 5 seconds. I normally turn the key on and wait until it finishes before I crank.
I was wrong mine does have a lean spike when cranking. Doesn't get all the way to 35. Toped out at 23.8. mine dropped out of closed loop after .13 second. I wonder what the fuel and spark are doing during the Syncng?
I wouldn’t worry too much about lean spikes during crank. But if it stays lean more than about 1 second after successfully starting, something is wrong. In your case, if it goes to the 20s and stays there for any measurable amount of time, I would look for tuning related issues in the startup enrichment settings and the top left corner of the fuel and target afr maps.
That’s a pretty high number. You are likely to spend very little time operating the vehicle above 20% throttle, so closed loop is only going to work on heavy throttle situations. That may or may not be what you are looking for.
@@LeechMotorsports good point! I was thinking that once it started cl compensation, it would continue. I'm out of 1D tables with flex fuel and boost builder things. I'll go back and watch what you did in the 2D table and set something up. Thanks for your response!
I don't have this issue because i have my idle area + or - 5% because I don't want it adding or taking away any fuel at idle since the map is fairly spot on around idle.
That's ultimately the correct long-term solution. But because this can get in the way even early in the tuning process, this workaround may still be of value to many. Agreed though, giving these things huge authority over fuel correction is a TERRIBLE idea. Too many times I've seen others bring in tunes from other "tuners" and the max correction for closed loop AND learn are +-100%. Lol.
On my 92 f-150 I put the terminator x,had it tuned and ran it for months, a few nights ago this happen.why would this happen? Do you think my o2 sensor went out? Or a injector went out?
While there can be truth to "false" o2 sensor readings when there is a lot of overlap between the intake and exhaust valves, the overlap alone isn't going to cause the readings to go to full rich or full lean, as described in this video. As for the 113 LSA number specifically, that isn't what's going to cause weird readings... it's the valve overlap amount. And while lowering the LSA of the cam will directly increase overlap, the duration numbers are going to play way more heavily into that. The quick formula I use for determining valve overlap is: ( ( (Int Dur + Exh Dur) / 4 ) - LSA ) * 2 So a 113 LSA with something like a 226 duration int/exh at .050" lift is still at 0 degrees overlap at .050". But 113 LSA with a 254 duration int/exh at .050" lift pushes 28 degrees of overlap at .050" lift, which will definitely start to mess with o2 readings. Moral of the story is that it's all about the complete cam specs, not just the LSA.
Unfortunately, the sniper systems do not currently support Time-based 2D tables. That said, I've never seen this issue on a Sniper system, only on the Terminator X systems. Can you confirm this is an issue you are actually having on a sniper system? Would be good info to know for future reference, and maybe I can find a slightly different approach that would work for you.
@LeechMotorsports thanks for the response. Turned out to be a bad o2 sensor. Got a new sensor and went away, then went to get a dyno tune. The basic tunes created are too rich, I think that's why they foul so soon.
@@carlosangel8773 Agreed. Seems like most handheld tunes I run across have target AFR in the 13s, even on stuff with stock or very small cams without a lot of valve overlap. That combined with really low timing creates a scenario where plugs and o2 sensors like to take a dump quickly. Glad you got it resolved.
That’s different. Likely just a tuning issue where you need more fuel in the low kpa decel areas of your base table and/or richer target in the same area. Also, you may actually want it to be lean during decel as long as the fuel returns smoothly as you approach idle.
I see that often as well. In your situation, do the exact same thing but set up the advanced table to override the cl comp - limit override instead of cl comp +
@@LeechMotorsports I am similar. AFR reads 10.8-11.2 and stumbling, while wideband LED is blue. As soon as the led goes green the engine smooths right out, if I just leave key on until it goes green runs perfect right away. I notice CL COMP is -50 while led is blue and it’s running rich/stumbling. Do I want to do the same with cl comp - as well?
Thank you so much!!!!
My garage no longer stinks at start up!
Thanks Matt!! Nice and simple! As you may recall, I have this issue, sent my ECU back to Holley from Australia just to have them send it back saying no problem with it 😕
I can now add some compensation back around the idle rev range as I had to zero it out. Thanks mate!!!
Oh yes. Your car was the one that really inspired this experiment. Hope this helps.
Already added it to the tune and works a treat 👍👍 Thanks again!!
This is exactly the video I've been waiting for! I have this problem, but I've been ignoring it. But I'm fixing it right now, thank you!
You guys are AWESOME! Thank you for all your hard work! 💯👊🏾
Thank you for keeping up with these videos. You have helped a lot on my fox 93 with terminator.
Finally. I’ve been trying to figure this out and been around and around with Holley for two years about this.
This info is gold! Thank you sir.
Another quality video from Leech Motorsports. My car has the opposite problem, it stays at 9.6 AFR until the sensor heats up, it tries to idle but will usually die before the sensor is warmed up, if I keep my foot on the gas then it will stay running. After the sensor warms up and starts reading it idles. Looking forward to the next video.
If you are confident the 9.6afr is a false rich condition, then try this same technique but with the cl comp - limit override.
I have the same issue and doing the same thing but with the cl comp - limit and it took it away.
Did you ever figure this issue out? Dealing with the same thing. Should cl comp limit be 0% or should it be higher to allow it to pull more fuel away
@@stephenmaggard1280did you ever figure this issue out? I am having a very similar problem. Should cl comp be 0% in 1d table or more to allow it to actually pull more fuel away ?
I have this issue also. 9.6 afr with no change until 30 seconds in it want to die. Then the sensor will start reading and engine will even out. What was your solution to fixing this?
This is perfect for folks. I really wished the Terminator X/X Max had more tables.
I have been chasing this exact issue since you tuned my car years back. I’ve learned a few things… but don’t know what to make of it. Holley warrantied my O2, no difference. I sent my computer to them, they said no problems.
I think it’s 100% in the heating logic. I learned the following: if I go key on, engine off for that same 20 seconds… the problem won’t be there when I start the engine. If I watch the lights on the ECU the O2 light will be yellow, then turn green eventually. If I start after the green, no problem. It’s as if the heating circuit is lazy, not the sensor itself.
Now here’s another odd thing… I went down the “maybe my starting voltage is low” line of thinking… replaced battery, re-did grounds (and added 3 more), changed to low amp draw starter… no change. During this time, I noticed that if I put my battery on a trickle charger for 15 minutes, the issue went away! I don’t have any draws and it’s always at full voltage after sitting for any extended periods.
It also will seldom (very rare) display “heating” instead of “initiating” on the handheld after a long hot drive. Very rare, and very random.
Anyways- don’t know why it took so long for me to find this video. Going to implement the change now. It’s a real bummer Holley doesn’t have a fix for this!
Working great after implementing. Over the past 2 years dealing with this- I noticed that the hotter the engine, the shorter the 35.6 hang time.
I used a 2D table with time and CTS. Seems to be working great!
I had this issue and it turned out to be a bad header gasket and a bad collector gasket. Changed those and AFRs went back to normal.
I had this problem, and this worked
Thanks
Going to try first thing tomorrow!!
My Terminator has been doing this after driving for a while! Especially on the highway when I give it some gas to pass or something.
GAH YOU ARE MY SAVIOR
Fixed my problem
The two most common reasons I hear for this happening is Holley EFI has a shit heater control strategy, and sensor placement. Most guys, myself included, just stuck it into an old narrow band bung on the header collector. Which sits at about 3 or 9 o'clock on the pipe. Ideally a wideband wants to be at 2 or 10 o'clock. Something about moisture running out of the sensor at 2 or 10, that just sits there at 3 or 9.
That's interesting 👍
I’m leaning toward heater control logic. But it’s just one of those things we can’t directly see and manipulate in the tune, so it’s hard to say.
Super cool info!
do you have a log you can show of this scenario? i'm just wondering if the ECT sensor is in an air pocket or something? i can't imagine the o2 is causing this problem?? but whatever the cause, good fix! almost like OEM.. :)
Good video but I tried what you described tonight an it did not work. Still dumping fuel when engine is warm. Help
I will have to do a log and see if I can see this, I have never noticed it on mine. I do have the fuel pump prime set on 5 seconds. I normally turn the key on and wait until it finishes before I crank.
I was wrong mine does have a lean spike when cranking. Doesn't get all the way to 35. Toped out at 23.8. mine dropped out of closed loop after .13 second. I wonder what the fuel and spark are doing during the Syncng?
I wouldn’t worry too much about lean spikes during crank. But if it stays lean more than about 1 second after successfully starting, something is wrong. In your case, if it goes to the 20s and stays there for any measurable amount of time, I would look for tuning related issues in the startup enrichment settings and the top left corner of the fuel and target afr maps.
I just enabled the TPS to enter Closed Loop. I set it to 20% and it seems to have covered up my issue.
That’s a pretty high number. You are likely to spend very little time operating the vehicle above 20% throttle, so closed loop is only going to work on heavy throttle situations. That may or may not be what you are looking for.
@@LeechMotorsports good point! I was thinking that once it started cl compensation, it would continue. I'm out of 1D tables with flex fuel and boost builder things. I'll go back and watch what you did in the 2D table and set something up. Thanks for your response!
I don't have this issue because i have my idle area + or - 5% because I don't want it adding or taking away any fuel at idle since the map is fairly spot on around idle.
That's ultimately the correct long-term solution. But because this can get in the way even early in the tuning process, this workaround may still be of value to many. Agreed though, giving these things huge authority over fuel correction is a TERRIBLE idea. Too many times I've seen others bring in tunes from other "tuners" and the max correction for closed loop AND learn are +-100%. Lol.
On my 92 f-150 I put the terminator x,had it tuned and ran it for months, a few nights ago this happen.why would this happen? Do you think my o2 sensor went out? Or a injector went out?
I've heard a cam with a LSA lower than 113 can create a false lean condition for the O2 and causes the system to dump fuel. Is this true?
While there can be truth to "false" o2 sensor readings when there is a lot of overlap between the intake and exhaust valves, the overlap alone isn't going to cause the readings to go to full rich or full lean, as described in this video.
As for the 113 LSA number specifically, that isn't what's going to cause weird readings... it's the valve overlap amount. And while lowering the LSA of the cam will directly increase overlap, the duration numbers are going to play way more heavily into that.
The quick formula I use for determining valve overlap is:
( ( (Int Dur + Exh Dur) / 4 ) - LSA ) * 2
So a 113 LSA with something like a 226 duration int/exh at .050" lift is still at 0 degrees overlap at .050". But 113 LSA with a 254 duration int/exh at .050" lift pushes 28 degrees of overlap at .050" lift, which will definitely start to mess with o2 readings. Moral of the story is that it's all about the complete cam specs, not just the LSA.
Good video, problem is on my sniper I cannot find the time under the x axis. Another tab I could use or is this only useful for the terminator?
Unfortunately, the sniper systems do not currently support Time-based 2D tables. That said, I've never seen this issue on a Sniper system, only on the Terminator X systems. Can you confirm this is an issue you are actually having on a sniper system? Would be good info to know for future reference, and maybe I can find a slightly different approach that would work for you.
@LeechMotorsports thanks for the response. Turned out to be a bad o2 sensor. Got a new sensor and went away, then went to get a dyno tune. The basic tunes created are too rich, I think that's why they foul so soon.
@@carlosangel8773 Agreed. Seems like most handheld tunes I run across have target AFR in the 13s, even on stuff with stock or very small cams without a lot of valve overlap. That combined with really low timing creates a scenario where plugs and o2 sensors like to take a dump quickly. Glad you got it resolved.
Mine is running great but goes full lean when I let off the throttle?
That’s different. Likely just a tuning issue where you need more fuel in the low kpa decel areas of your base table and/or richer target in the same area. Also, you may actually want it to be lean during decel as long as the fuel returns smoothly as you approach idle.
I'm having a similar issue but my afr sticks at 9.6 for 20 seconds
I see that often as well. In your situation, do the exact same thing but set up the advanced table to override the cl comp - limit override instead of cl comp +
@@LeechMotorsports I am similar. AFR reads 10.8-11.2 and stumbling, while wideband LED is blue. As soon as the led goes green the engine smooths right out, if I just leave key on until it goes green runs perfect right away.
I notice CL COMP is -50 while led is blue and it’s running rich/stumbling. Do I want to do the same with cl comp - as well?