Need Help Bad. I just had a new ls1 installed and the car will not stay idling unless you stay on the gas. This is a forged ls1 (347) with 9.0:1 compression with a comp cam 220/224 114lsa in an automatic built by one of the sponsers. The way it idles sounds like it has a cam bigger than a T-Rex cam. The car backfires really bad to the point where you can see fire out of the exhaust. If you put in reverse it dies, and if you put it in drive it will move for a second or two and die. The car has been set to idle at 750 rpm in gear and 850rpm in p/n with HPTuners. The crank position relearn has been performed. And the computer is throwing a P0336 code. Furthermore, now my dash rpm gauge does nothing, it stays at zero. Could there be something wrong with the engine.

Any suggestions would be great at this point.
Thanks

 

Who installed her? Don`t mess it up, take her to someone that knows how it should be! Good Luck.

 

check the ground wires that bolt to the back of the driver's side head. there should be 3 of them I think. Those wires control ground to the gauges and to the ignition. I found out myself how bad they can make life if not hooked up properly.

 

Did you plug the MAF and IAT sensors in? Both will cause similar simptoms, also ground for the coil packs, and like Timberwolf mentioned, the ground wires on the back of the head, although I'm pretty sure your car won't start at all without them getting some contact.

 

Your car is running really rich is what it sounds like. You can flip the idle screw over on the tb and open it up more to let the car idle. You need to check the grounds and get some tuning done.

 

I have an update and its bad, place a new crank sensor in ran fine for a few a seconds and all went to hell again. My installer has done several ls1 engine swaps and also is a a damn good engine builder. The crank is screwed up at the crank trigger and the reluctor wheel is cracked. There was a hole drilled in the crankshaft reluctor wheel. I'll take pictures later today and post them

 

So how was a hole drilled in the reluctor wheel?

 

The guy who installed it is both GM and ASE cert and has worked for GM for at least 5 years and has BUILT many local LS1's, including the turbo motor in our LS1 which has performed flawlessly. The guy knows what he is doing and personally I wouldnt trust anyone else to do work...so I know thats not the prob. I know of a handful of engines he has built and not one has failed.

Anyway, I spoke with him today and he said its something with the crank, i know because of the way it was built, it at least damaged the pos sensor when they started the car...more details later.

As for the sponsor who built the motor, I dont want to jump to early conclusions so we will leave that aside for now...have yet to talk to them...

Also the car had the stock motor in it when it arrived for the new motor to be put in, so that sorta rules out any PCM or electrical probs.

EDIT: I didnt see that thriller had posted...sorry kinda redundant

 

Give the sponsor a call first before anything. I KNOW they CAN and WILLl help you out. Have you called them yet??? I know when most things go south sponsors like to hear it from the customer, not on a message board.
Kyle

 

omg are you serious?

Who assembled your motor?