Thread: LTFTs changed, why?

So last time I scanned my car it was like 2 or 3 weeks ago and my trims were right on spot.

Today I scanned it again and now the LTFTs are in the -22s STFT are still on target.

I haven't done any changes since then. Why could this be?

yes

^yup

got it. I didnt think it would make that much of a difference. I will just have to create a diferent tune for every season. thanks.

i think it was between 20 and 25 Celsius during the day when I tuned the MAF table, always let the trims relearn. The trims were on target during the rest of the tuning process (a few weeks). Right now it's between 24 and 34 C during the day.

I actually scanned today during the hottest hour of the day in traffic and with the A/C turned on to get the ETCs near 100 C. I wanted to make sure that I wasn't getting any KR at that temp.

I'm not sure what you mean with that. Do you mean letting it sit for a while? If that's the case, then I don't know I only noticed that today on the way back from the office. I haven't scanned it again since then.

I haven't deleted the evap either.

Here's the average LTFTs that I got today:

No, I actually deducted timing at higher IATs and also deducted timing to the ECT/spark table past 90*C since I was getting some KR at this point. So the objective of doing this scan was to check if it actually worked, and it did.

I also scanned it again the a couple of days later and the LTFTs were back in place. I guess they change when driven at higher ECTs and with the A/C turned on.

I don't use HP tuners by the way, it's DHP too.

Oh I see now, that explains it all. Then I can leave it as it is for now. I may not need to pull timing at higher ECTs once I get the IC installed.

Thanks