Help!!!! LTFT's and STFT's

erod550 · Postby **erod550** » Thu Apr 19, 2012 9:14

I seriously doubt you'd get a CEL if you'd left it alone. The ECU is doing its job adjusting and 11.8 AFR is fine. I was running 12.1-12.5 with my pro-tune. Direct Injection is able to run leaner than port injection because the mix is done right in the cylinder.

But I know how it goes with not wanting to feel uneasy with the car even if you know nothing is wrong. It's the reason I got rid of my HKS SSQV. It sounded like compressor surge even though I know that's just how the thing sounds. It worried me all the time even though I knew nothing was wrong so I got rid of it and got a Synapse.

But really, thousands of these cars are running an intake with no AP with no problems whatsoever.

hcbr929rr2 · Postby **hcbr929rr2** » Thu Apr 19, 2012 9:14

yeah i figure I'm buying my AP in about two weeks, it took me 20min to swap back to stock, I don't mind wasting 20min for peace of mind lol

tbot · Postby **tbot** » Sat Apr 28, 2012 9:14

sounds to me like a leak, even the smallest one will through your trims off. had that happen to me over the various installs i've done and there's something a miss. fuel trims should be as close to 0 as possible. Basically whats happening is your maf is reading a certain amount of air coming into the engine and fuel is added based off that. trims will adjust based on the afr the car is reading. so basically your ecu is telling you its adding a shit ton more fuel than what the maf is saying it should have, meaning more air is entering the system after the maf has made its reading. even with a CAI your trims should be close to 0 (+ or - 5ish) even without remapping the ecu. a sri on the other hand usually throws it off because there's not enough tube for the air to straighten out properly and doesn't get a good reading.

either way, check everything again, and reset the ecu by disconnecting the battery for 5 minutes and see what happens. you will be able to tell rather quickly based of ur STFT if there's still an issue. Also note, the stft is added on top of the ltft iirc.

hcbr929rr2 · Postby **hcbr929rr2** » Mon Apr 30, 2012 9:14

well I went back to stock and my LTFT's are -3.9 up to +3.0, which seems to be exactly where they should be, I ordered my AP this morning, as well as the Cobb TIP, the only place I could think I may have had a leak would have been where the TIP meets the turbo, cause thats the only connection I didn't check since I didn't take the stock TIP off the first time. So when I install the SRI/TIP combo next weekend I'll have the AP too, everything should go smooth that way

erod550 · Postby **erod550** » Mon Apr 30, 2012 9:14

If it's worth anything my stock TIP pulled right off the turbo without even loosening the clamp. It was already loose. I'm not the only person that found their stock TIP loose like that either.

hcbr929rr2 · Postby **hcbr929rr2** » Mon Apr 30, 2012 9:14

I've heard that before, guess I'll find out when I swap to the cobb TIP, but wouldn't my LTFT's be a little whacky even now if that clamp was loose?

erod550 · Postby **erod550** » Mon Apr 30, 2012 9:14

Yes. If all that changed was the intake and your fuel trims are fine now, you probably don't have a leak. It's probably just the MAF housing size issue discussed earlier. And Cobb SRIs come with an air straightener (newer ones anyway) so that shouldn't be an issue either. The AP with calibration for the Cobb SRI should fix things right up for you.

Help!!!! LTFT's and STFT's

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