I'm thinking this is a carb issue, but not completely certain.

1987 Camaro Z28, 305, Edelbroch carb, intake manifold, headers, exhaust, HEI distributor, advanced pulley system, 104k.

This issue has happened for several years and no one can seem to pinpoint the problem, nor can I always prove it by leaving the car overnight at a mechanic. When the car sits for over a day, week, week, etc and the weather is cold, I start the car and instead of the idle jumping to 1800rpm or so as it should being carbed, it will sit at near regular idle speed for about two minutes and slowly get to where it should be. In the meantime, the idle is bouncing, the car is rocking, smoke is puffing out...

http://www.youtube.com/watch?v=cBkr4...ature=youtu.be

Notice at :30, sounds like I have a mean cam in there...but stock

Notice at 1:40, completely smooths out and smoke changes to white (because it is cold out).

Usually it starts with blue smoke, but for some reason this time it was darker and smelled more of gas (running rich?)

One mechanic told me the carb could be warped and it is typical of a polished (edelbroch) carb.

Any suggestions would be appreciated. It ONLY happens on a cold start and then the car runs beautifully. This is an embarassing problem. Neighbors probably choking inside their houses lol. HELP!

 

Electric choke? Do you pump the throttle a couple times before cranking? That also sets the choke.

And at about 30 seconds, god I love how it sounds, haha.

 

Pop the hood, remove the air cleaner, cycle the throttle & watch the choke & the linkages. Does the choke linkage go to the fast idle setting? Is the choke closing all the way? Is the choke getting 12volts? Are the linkages clean?

 

I think is sounds sick.. thats how my 305 TPI sounded and I had alot of great feed back. Maybe it just needs a good rebuild, is it a stock short block or long block? Maybe could use new rings and/or have the heads gone though. Just tell your neighbors that how race cars start when is cold out.

 

SD and Robby - Yes, I pump the gas a little just before a (cold) start. And I love that :30 second sound too but that's only happening because there's a problem! A rebuild could be in order, I'm thinking moreso with the carb. Car runs great otherwise.

ex - Should I be cycling the throttle prior to the start or just after it is started (while it's having that problem)? I do know that if I start the car and let it do it's thing like in the video, it will eventually get over 2000rpm and if you blip the gas it will get down to 1800rpm. So that could mean that it's set for the higher rpm idle, but something is restricting it to get to that point(?) I'll have to get a reader to measure the volts. Would putting up a video of the carb during the cold start be useful? I usually only get to my car on weekends. Hopefully next week I can check it out again.

 

Do you know that you have to pump the pedal once to set the choke?

 

It wasn't apparent in the video, but I did pump the gas before starting the car. My driver's side is against a wall so I didn't want to bang the door rushing out to make the video.

Also, if I didn't mention it before, this carb has an electronic choke.