TheBigAL

A friend of mine recently put a 125 kit on his LT1. At the dragstrip it always goes into limp mode at about 60 mph when he sprays it. Right after we left the track tonight he pulled out on the road and from a rolling start it did fine. What might be causing this? I dont really have any experience with nitrous. Just trying to help him out.

joelster

I'm assuming it's a dry kit. Possibly causing the MAF to read way off. Can he jet it lower?

nitrous2fast

iTrader: (2)

What is your definition of "limp" mode?

There is an abuse mode for the trans.....

TheBigAL

That may be the problem. he says it causes it not to shift out right and said it sometimes hits the rev limiter.

TheBigAL

I think the nitrous kit only came with the jets for 125. So you think the 125 is too much for a dry kit? How about if the car was tuned?

TheBigAL

The service engine soon light comes on whenever it happens. I forgot to mention that.

RamAir95TA

iTrader: (2)

Have it scanned.

LT1FirebirdSLP

iTrader: (2)

Gunna need to know what codes you are throwing.

myltwon

iTrader: (1)

If you stroke the motor it won't go into limp mode.





What year car is it? Likely it's the "stall wall" issue that many have had. Basically the tailshaft is flexing on the transmission slightly causing the VSS to lose signal. Problem is since the transmission is looking for a specific mph to shift at but isn't reading a signal it throws the transmission into limp mode. This issue has to be tuned out, making the transmission only shift by rpm not mph on the 1-2 shift.

LUNATIK LT1

holy **** I just pissed myself, nice start to my friday here at the shop

- Have you checked your tps voltage? I had a similar problem long time ago where under wot it would "bang" into 2nd then go into a limp mode. ---- oops this is a later reply. forgot to hit submit......