Thread: SS M90 misfiring due to tune?

With my Intense PCM, my STFT is -0.7 to 4.6 at idle. My LTFT is 12.5 at idle. I'm contemplating just biting the bullet ad getting HP tuners and learn it myself. This is so frustrating.

You'd also want to invest in a wideband.

Although arent you trying to sell one?

Either way. Those tunes are wrong or you have mechanical issues.

STFT's dont mean much. Pay attention to the LTFT's.

Originally Posted by matt5112

You'd also want to invest in a wideband.

Although arent you trying to sell one?

Either way. Those tunes are wrong or you have mechanical issues.

STFT's dont mean much. Pay attention to the LTFT's.

Yea maybe I'll just keep it. I don't have a spot left in my gauge cluster though. Need to find a place to mount it.

HUD pod or in the cubby below the ashtray?

MAF table could be off by that much too.....I've seen it that way. But even with the Intense pcm, it suggests something isn't right.

Kinda off the wall, but have you checked the O2 sensors? If it's going bad, it can throw a tune off also.

Originally Posted by Reptile

MAF table could be off by that much too.....I've seen it that way. But even with the Intense pcm, it suggests something isn't right.

Kinda off the wall, but have you checked the O2 sensors? If it's going bad, it can throw a tune off also.

Hmmmm. I'll have to look into the O2 sensors. Reptile, where is your shop?

I'm near Kansas City, MO

my LTFT's were all around 12 all the time.

Even with no vac leaks, exhaust leaks, brand new O2.

Tune was off since it was tuned with an exhaust leak first time around.

Wouldn't it throw a code if the O2 sensor had a problem?

Well sure, it can, and it should, but I've seen where they won't throw a code. It mostly does it when it doesn't "switch" like it should. What I was getting at, is that I've seen an O2 sensor make a difference of +- 8 just by switching. Denso, Delco, they seem to read different.

But then again, I've seen stock tune cars, factory everything go +12 on a scan.