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Discussion Starter #1
Like a few users of the BOE tune I've been having intermittent stalling/idle issues. I've replaced the typical things recommended and I've detailed that in the large Torque200 thread. Even after that I still have stalling and idle issues. I found a post on how to check for vacuum leaks via the fuel trims. I see that Fastworks has an option for this in the data logging, but I can't seem to get this feature to work. Per the thread below it seems the base FW software comes with this ability. Am I reading that correctly?


I'm getting very frustrated with this issue. I bought the the tune in August last year, took a while to get it, and when I did I haven't been able to fully enjoy it. It almost isn't worth the money given my troubles. I swapped back to the original tune and the car has no issues now other than a VIN mismatch CEL.

Any help is appreciated. I'm trying to work this through BOE in parallel and will continue to do so, but aren't having any result. My symptoms can be found in the thread below.

 

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Discussion Starter #2
Small update for those that might find this thread helpful. I finally got around to checking some data between the stock tune and TQ200 via OBD. It seems my STFT is way off with TQ200. Below is a screen shot from idle when the TQ200 tune was installed. Stock idle STFT hovered about 0.
 

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LTFT is basically the integral (summation) of STFT. So if you have a nonzero STFT then you'll see the LTFT slowly change. This drives the STFT down since the LTFT is compensating for the STFT, and eventually they will stabilize when STFT=0 and LTFT=/=0. Seeing your STFT pegged out (well, beyond pegged out. Service manual says the max is +/-17%) and yet the LTFT=0 tells me that it is in open loop. If you unplug the pre-cat O2 sensor, does it idle differently? And that rpm seems very high; is raising idle part of the tune or is the engine still cold? If it is cold, it could simply be that the O2 sensor isn't active yet
 

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Discussion Starter #4
This was taken after about 10 minutes of driving and logging on the base tune. This doesn't include the 20 minutes drive to the shop. After that, I turned the car off and loaded the BOE tune. I then let the car idle and that's when that picture was taken. I'd say the car was warm.

I dont see why I'd need to unplug the o2 sensor and check. The car runs fine on the base tune. If the base tune was having issues I could understand that suggestion.
 

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The car runs fine on the base tune. If the base tune was having issues I could understand that suggestion.
The idea now is to figure out if that -29.7 STFT is "real" or not. Since the base table changed with the tune, the trims are of course going to be different, but hopefully better. That's part of the idea of getting a tune. If it is real, the new base table then it means is wrong by nearly 30% and the ECU senses that with the O2 sensor and corrects it. Because it corrects it, it runs better than if it didn't. Now, if you unplug the sensor, the ECU is no longer correcting for the 30% error you reported and will run worse.
 

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Discussion Starter #7
Update: BOE finally got back to me after constant friendly reminder emails (no sarcasm) I sent them. I'm not sure what Phil changed, but at idle my STFT is pegged at 0 or slightly negative. I let the car idle for 10 minutes and gave it some revs. There was no quick drop in RPMs after letting off the throttle and it didn't sputter at all while idling. Seems to idle about 800 rpm. I haven't gone for a drive yet, but first test results are ok.
 

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Update: BOE finally got back to me after constant friendly reminder emails (no sarcasm) I sent them. I'm not sure what Phil changed, but at idle my STFT is pegged at 0 or slightly negative. I let the car idle for 10 minutes and gave it some revs. There was no quick drop in RPMs after letting off the throttle and it didn't sputter at all while idling. Seems to idle about 800 rpm. I haven't gone for a drive yet, but first test results are ok.
Does it start up right away without having to crank it once or twice now?
 

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Discussion Starter #9
I never had a starting problem. The prior version of the tune fired right up each time.
 
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