1999ssls1

iTrader: (71)

I have an InconTT 370 trans am. I am having a problem with it cutting out while reving in neutral and while in gear at 3600-4000 rpms. The car starts sputtering almost like it has a 2 Step in neutral when you rev and at 3600-4000 rpms in any gear, but only if you stay at that rpm. If you just start out at idle or anything below say 3k, it does fine. It is not doing anything strange on the scanner either. Anyone know what is happening?

Thanks

black98ws6ta

iTrader: (77)

If the car is tuned with a maf I would say the car is going into pe and goes pig rich at that rpm.

1999ssls1

iTrader: (71)

Sorry. It is a OLSD tune. Like I said it doesnt do it if you just stay in it from idle or under 3k.

black98ws6ta

iTrader: (77)

It still may be fuel related..do you have a wideband on the car? If so I would expect for it to be doing something funny when it is acting up.

1999ssls1

iTrader: (71)

No I do not. It was dynoed about a month ago and the AFR was 11.5. What should I look for?

black98ws6ta

iTrader: (77)

I would assume rich in that area, but could also be lean.

1999ssls1

iTrader: (71)

Why would it only do it sometimes though?

black98ws6ta

iTrader: (77)

In your origional post you did not say that it only does it sometimes. If you recreate the same load and same senario and it is intermittent, then you may have another problem. BUT...you can be at the same rpm but under a different load and the a/f be two totally different numbers, possibly causing the problem.

To go any further you may need a wideband, or a very accurate discription of what it is doing. Narrowband 02 sensors may also tell you something if you still have them.

1999ssls1

iTrader: (71)

When I said sometimes, I meant only in neautral or hitting it at a given rpm. It feels great if I go from from a lower rpm, it then has 0 problems. The car was tuned at a reputable shop. Do you think its ok to beat on if I hit I start a lower rpm? I still have the factory o2s.

black98ws6ta

iTrader: (77)

I just think it has a bad spot in the tune, but would reccomend a wideband to verify before moving any further. You can look at the 02's while it is acting up.

1999ssls1

iTrader: (71)

Do you have efilive? I can show you the tune.

tomz28

iTrader: (20)

put a wideband on it like NOW it can help you out in so many ways and dont beat on it i could cost you in the long run

sevanseriesta

iTrader: (34)

if you are in OLSD why do you still have factory 02's they are no longer doing any reading

Silver_TransAm

iTrader: (2)

What?

SD only takes over when you go into boost. The rest of the time it drives like normal using all sensors. Thats why sd is preffered.

Just try disconnecting an o2 and find out, it runs like ****. Ask me how I know.

black98ws6ta

iTrader: (77)

OLSD means open loop speed density, which means it does not use any 02 sensor readings for correction. Closed Loop must be how your car is tuned.

If you car does not have a maf it is sd, all the time. If it is closed loop the 02 sensors help correct any error in the tune.

Silver_TransAm

iTrader: (2)

Oh ok. Did not know there was a OLSD and SD.

I have no maf. Mine must be Closed loop then.

Which do you think is better? and why?

Just curious.

Sorry.