well i just picked this car up the other day, my first ls1, the issue im having is that when the car has been sitting all night and is cold(which these past couple days means its about 29 degrees out. the car will start right up then chug out and die. but if i hold the revs up to like 1500-2000 or so, itll keep running, but you can feel it running like crap...after a couple minutes or so once it starts to warm up a bit itll run fine, like nothing ever happened. anywhere i can start looking to diagnose this? btw this is on a bone stock 98 ls1, still got the paper air filter

 

I had a couple of cars do that in the past. Nothing on my camaro yet. But with my other cars it was a bad egr.

 

yeah i never thought of that, i was thinking maybe something to do with the AIR system because its only right at startup, or the IAC or MAF. Im gonna snag the maf off my 94 and see what happens as well as try and clean out the throttle body. is there any way to unhook the egr on an ls1? like unplugging a sensor or something so i can diagnose it?

 

I havent a clue. I had those probles on a 95 t-bird it had a 4.6L V8 in it. the EGR was sticking when cold but after it warmed up it ran fine. I took it into a dealer thats what they said it was so I replaced my self and it went away. Never really got in to the EGR on my camaro yet so I don't know if there are even any similarities between the Ford and GM setups.

 

Surprised you're not throwing a SES light - if you don't have a scanner I'd bring it by Auto Zone and have them check for any codes just to be sure. Don't think it's the AIR system, you can disable that by just removing the AIR PUMP fuse under the hood - will throw a code though (P0412 on mine) then go back off by itself after a few cold starts. Don't have EGR on mine but you can probably temporarily disable that too by just unplugging the electrical connector.

 

Is the car stock? If so I would start by swapping the IAC.

 

This was my first thought too.

 

98s have a startup table but used to not be able to access it, HP tuners can now access it and change the A/F and idles so u might wana get it tuned anyway.

 

well i swapped in a granetelli maf i had laying around, blasted the crap outta the throttle body and iac porrts with brake cleaner, and popped in a new air filter. it fired up and held a great idle, although it was warm i could tell that something was different as it shifted alot smoother and there was better throttle response. on to plugs and an air lid...