I have a 1987 Camaro Z28, 305, Edelbroch Carb, Edelbroch intake manifold, Edelbroch headers, HEI distributor, Advanced Pulley System, Edelbroch exhaust. Once the outside temperature goes below 60 (and worse the lower it gets especially during the winter), the engine seems to stumble for a bit until it can finally get to the 1800 RPM start up speed. It starts up no problem.

As you can see in the video, the engine (cold) starts but stays at a low RPM for a carb'ed engine. The engine and tach bounce around quite a bit. While this is happening blue smoke is coming out the exhaust. Eventually, as the RPMs slowly climb to where they should be on a cold start, the engine is smooth and no smoke at all is coming out of the exhaust.

This has been happening for years. Mechanics never get to see this even when they keep the car overnight and cold start it in the morning. It seems the car has to sit for a few days and temps outside have to be cold otherwise this will not happen. This NEVER happens during the warmer months of the year.

Any ideas? Oh, at 48 seconds in the video that was me hitting the gas for a second.

http://www.youtube.com/watch?v=LybkYgRk7wk

 

The car runs rich on cold starts, that's how they're designed, to help keep them running until the engine gets up to temp, so that culd have something to do with your "blue smoke". Could also be your valve seals not being perfect and expanding as the car warms up. I'd say as long as it gets to the 1800 and runs fine once it's there, you're probably ok. It's just the nature of carbed cars. hehe Mine runs like crap until unless I give it a good 2 min to run at high idle (no neighbor complaints yet, but I'm waiting...) to warm up.

 

I guess it's just a little embarassing. As you can see in the video, it's takes quite some time to get up to the normal cold warm up idle. It will actually be smoking up until the car's done literally bouncing and rocking and configures itself and gets to 1800prm. Also, if it was a fixable problem, I'd like to fix it obviously lol.

 

the blue smoke in the morning is usually a sign of bad valve seals. 1800 seems like a high idle to me. but yea, its the nature of a carb. gotta warm it up for a few.

 

With an electric choke, it should jump to high idle without struggling to get there. Since it's not, the choke/carb might need a rebuild.

Now, without the higher idle, when you put it in gear and it's cold, it will die. I also have a 67 Camaro with no choke on it. I have to hold the gas pedal at 1800-2000 RPM for a couple of minutes or the car won't idle at all and will stall and die as soon as it gets in gear because there isn't enough fuel to keep the ignition running when it's cold.

 

Thanks guys. Hopefully I don't have to touch any seals until I get the engine rebuild sometime in the (distant) future. I'm thinking of showing the video to the mechanic since it can never be replicated and I will suggest the choke or carb being rebuilt. The Edelbrock carb might be around 10 years old, but with only a few thousand miles (which prob means nothing). One of my mechanics told me that the high polished Edelbroch carbs have an issue with warping, not sure how true that is.

 

Blue smoke is oil, but the running problem is just an adjustment. Find an old mechanic and he can set up your choke so that you push the gas pedal once, turn the key, and that's it. He will need to have it after it's been sitting overnight.