95 GMC 5.7 rough cold idle problem
 

I have a problem with my 1995 5.7 when I first start it up in the mornings. It idles real rough like it is flooded and will die when I put it in gear. (If I idle it up to about 1000 to 1500 rpm it runs smooth.) It will do this until it gets to normal operating temp then I can kill it and start it back up and everything works fine. This engine was just recently rebuilt and it has flat top pistons, 30 over, went one step up on the cam, stock heads, new distributer, cap, rotor, wires, plugs, fuel filter, fuel pump and so on. It has 1500 miles on it and ran great the first 1000 miles then started this. I have checked th IAC and it ohmed out good.

Any ideas???????

Are you getting an engine light. It could be a temperature sensor not telling the computer to richen it up on cold start. I had one go the opposite way and it would run rich all the time till it died. I would imagine it could do what your saying as well and not be richer on start up causing a cold natured situation.

No it is not showing a check engine or anything like that. I am going to try replacing the computer temp sensor this afternoon. If its not that I guess the next thing to try is the ECM. I just do not know what else to try.

I think the problem is solved. I changed the computer temp sender and it cranked up and ran just fine this morning. Outside temp was 25 this morning so I know everything was chilled.

Nice! It feels good when you fix it yourself huh?!?!?!?!

Yes it does! I was just about at witts end with this one.
Thanks for your input though!