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Huge changes in LTFT's

1803 Views 3 Replies 3 Participants Last post by  ms6ftw
I got my DH a month ago and was checking everything out. I noticed my LTFT's were +3% at idle, PT acceleration was +14.7%, and cruising was +11.7%. My first thought was "that's gotta be off" even tho I had no idea what this meant. These have been my numbers for the last month with no changes After reading the tuning section of the forum, I've determined it's pretty imperative that I get an AP and I plan to place an order for one next week. This thread is a 2 part question.

1) I live in Florida so the temperature has crazy changes here. It was 50's-60's high, then randomly in mid Feb. we get a whole week of high 70's. Since the warmer weather im getting higher numbers in my LTFT's as high as +16% cruising and 5% at idle. I know that warmer air means less molecules per square inch, ect but wouldnt that make my car lean out the fuel trims to adjust to less air? I purchased the car with an MS CAI and I added a SU test pipe but I'm not sure if the filter has ever been cleaned. It also has the hydroshield on it. Could a dirty filter + hydroshield prevent the car from breathing that much? Would cleaning the filter see even a minor drop in FT's? As far as I know the LTFT's are the ECU's adjustments to meet target AFR's and reduce KR, but I have NEVER had KR (possibly because FT's are so high lol) and I figured LESS fuel would be added if less air is being pulled into the system because of temp., dirty filter, humidity, etc.

2) When I do get an AP, should I just calculate the MAF on a stock map or would I be able to run stage 2 with just the test pipe? ( read a thread somewhere a while back that claimed you could "get by") I know COBB says that you need a full exhaust but I dont have the funds for that right this second and I kinda want to stay away from stage 1 because of the super aggressive timing.

Sorry for the long winded post, but thanks in advance to anyone who can answer any of the questions :lol:
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I would be more inclined to buy a DP before the CBE as I plan on going full exhaust anyways, and for the price of a used catback, I can get a DP. But as far as boost leak, I forgot to mention I recently installed a Forge BPV and my FT's didn't change, but I was spiking 19psi occassionally and would hold ~15psi for longer, whereas the stocker would spike 17psi and would hold for less time. Not sure why this is. I dont have a boost gauge YET, and these numbers are coming off the DH (not sure how reliable it is). I don't think I have a boost leak. Since i've installed the test pipe I have the "I smoke while idling for a few minutes" symptom, but now that it's warmer, Im smelling a little hint of burning oil after driving. Not sure if maybe just the blow by oil is being burnt off, or the warmer weather is making my oil more prone to being pushed through the seals.(still using 5w30). I'm not smoking at all unless idling at a light for 3-5 minutes, but when I do, it's pretty thick lol. If it is the blowby, would that oil effect FT's?
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