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Discussion Starter · #1 · (Edited)
hello everyone,

I'd like to ask You guys to take a look at pictures below.
Yesterday I decided to veryfy CE light before starting the engine and I saw it flash 7 times.
This is the adaptation problem, I know that, but I ran PCMscan to see what's going on and it turned out that STFT and LTFT are on crazy levels.

I heard that Trionic 5 might show wrong fuel readings on OBD2 but on the other hand there's this p0171 error that would mean wrong air/fuel mixture so all of the STFT/LTFT readings could be quite right, although they're too high.

Strange is that cars runs smoothly, no problems at all, neither with starting the engine nor driving or accelerating.
Sorry fot picture's descriptions in polish but I hope it's quite clear which is what.

Do You have any suggestions on this matter, or maybe some advices?
Is this possible that it's caused by some vacuum leak ?

thanks
 

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Discussion Starter · #2 · (Edited)
Isn't there anyone who could check his LTFT values on t5 ?
Or could confirm if it's possible to get such high numbers like I do ?

I'm a bit lost and don't know if I should look for any vacuum leak or try to search for the cause somewhere else.

I just saw that my previous images were heavly resized so I'm showing the picture with LTFT and other settings. Maybe someone could comment this situation.
 

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I'm not experienced enough to know the T5 trim levels. I've never tuned or looked at the numbers.

Start with the basics:
are you sensors in nominal range? check resistances
how old is the sensor?
while the car is idling, spray carb cleaner around the intake area and see if you get rpm spikes, if so, find the vacuum leak.
 

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Discussion Starter · #4 ·
Fc saab, thanks for Your response.
After long research I managed to get some info on LTFT t5 values on Trionic forum. As the t5 is not able to show more than 25% trim, we need to use a formula as follows:

100 = 25%
-100 = -25%

Should be something like this (i.e. for -62%, and 91% LTFT values):
-62 = ((25/100)*62) = - 15,5%
91 = ((25/100)*91) = 22,75%

In other words - we need to divide read values by 4.
It could be useful info for people who get high readings on t5 cars.

In my case values are still too high but I found out that my apc valve was bad and caused to overboost. It was leading to fuel cut while high engine load, what was probably the main reason for high injection times and also rised LTFT values.
 

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Glad you figured it out and thanks for posting the formula - I didn't know that it needed to be divided by 4. I've gotten that same code by accident when mapping for larger injectors when T5 couldn't trim fuel by over 25% which was needed at that time. So has your LTFT dropped since the new apc?
 

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Discussion Starter · #7 ·
Hi,

Not yet. As this is t5 APC I'm leaning towards changing it to t7. To do that I'm waiting for my cousin, who is supposed to bring me one from England in few days, and then I'll have to find someone to make the appropriate soft corrections and Ecu modification. T7 are said to be much less prone to damage than t5 (at least that's what I heard..)

But as soon as I get it, I'll post back and write the results.

I was one told about cleaning, but is there any special way I should do that?
Spray with dust air? Or dismount it and clean the whole thing inside?
I'd definitely prefer cleaining it only to swaping and making all these mods...
 

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Fc saab, thanks for Your response.
After long research I managed to get some info on LTFT t5 values on Trionic forum. As the t5 is not able to show more than 25% trim, we need to use a formula as follows:

100 = 25%
-100 = -25%

Should be something like this (i.e. for -62%, and 91% LTFT values):
-62 = ((25/100)*62) = - 15,5%
91 = ((25/100)*91) = 22,75%

In other words - we need to divide read values by 4.
It could be useful info for people who get high readings on t5 cars.

In my case values are still too high but I found out that my apc valve was bad and caused to overboost. It was leading to fuel cut while high engine load, what was probably the main reason for high injection times and also rised LTFT values.
Late to the party, but my LTFT numbers are very high, too (in the high 30s IIRC)...according to Torque Pro...

I had heard rumors that the T5 OBD II port give 'wrong' numbers...but the info was vague. The info in your post is clear and sums it up nicely. Thanks!
 

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hello everyone,

I'd like to ask You guys to take a look at pictures below.
Yesterday I decided to veryfy CE light before starting the engine and I saw it flash 7 times.
This is the adaptation problem, I know that, but I ran PCMscan to see what's going on and it turned out that STFT and LTFT are on crazy levels.

I heard that Trionic 5 might show wrong fuel readings on OBD2 but on the other hand there's this p0171 error that would mean wrong air/fuel mixture so all of the STFT/LTFT readings could be quite right, although they're too high.

Strange is that cars runs smoothly, no problems at all, neither with starting the engine nor driving or accelerating.
Sorry fot picture's descriptions in polish but I hope it's quite clear which is what.

Do You have any suggestions on this matter, or maybe some advices?
Is this possible that it's caused by some vacuum leak ?

thanks
Your baby, sir, is now 15 and probably needs maintenance in many areas, particularly in the rubber items .. CV boots, vacuum lines, etc. .. so , the CE lite system is emissions based, not on how well the car is running ..A vehicle could be running like crap, but if this affects emissions NOT , then no CEL
, at least right away .A bit strange , I know
You car is a 2000 .. should it not have OBD 2 which generates a PO xxxx code ?
 

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Discussion Starter · #11 ·
Like I wrote , it was p0171 error.
But after resetting ecu it never came back.

I've changed all vacuum pipes recently. My car is also very low mileage (around 100k) and all look quite fresh inside. But I'll take a closer look at all hooses again.
 

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Discussion Starter · #12 ·
By the way, I have a question:

Does anybody know if using hooses with smaller diameter may affect the performance and the APC ability of giving the appropriate amount of boost to the wastegate? Smaller hoose - bigger pressure, but less air, am I right ?

I have 3mm inner diameter in one of them (Apc -->wastegate) and I'm just wondering if this may cause the car to malfunction in some way.
 
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