new carb

[Guest 1onesy]

I have an 85 riviera with the 4 barrel that has all kinds of idling problems and whatnot.I don't want to deal with all the components and trying to figure out which ones are bad.So, can I replace my carb with an aftermarket one like edelbrock so i can disconnnect the computer plug and all that hosing and emission junk that does not function correctly anymore?

[sosuzguy]

Did you ever have any luck with this? There's a few things that can make it idle wrong that doesn't have anything to do with the carb.

[Guest 1onesy]

I've checked all the hoses yet the idle goes up and down and sometimes just stalls out

[sosuzguy]

the egr valve isn't bad is it?

[Guest 1onesy]

How do you know if its bad?

[sosuzguy]

I press up on the bottom of it and the engine stumbles then when I let go the engine goes back to idling correctly. There is a trouble shooting for it in the service manual. You can also take it off and visually check it out.

[Guest 1onesy]

so if the engine don't stumble its bad?

[sosuzguy]

if it didn't stumble then your egr didn't open or is blocked somewhere.

[Guest 1onesy]

thanks i'll check it out

[Guest pfloro]

If you live in an area which requires emissions testing and a visual inspection, you will not be able to remove the emission gear. Although a bit daunting at first, the GM CCC (Computer Command Control) system of that era is not really complicated. Your computer controlled Rochester 4bbl is a fine carb once it's rebuilt (if necessary) and properly adjusted.

Owning a car of this era requires a desire to 'get into it' or a trusted mechanic who is willing to troubleshoot for you. Jayson is knowledgeable about CCC and the factory service manual is your best friend (or your mechanic's!).

I am the original owner of an '84 Toronado with the same engine & CCC system (189,000 miles). It certainly needs attention from time to time, but it's all stock & runs very well.

Paul

[Guest TwoDoorBuickMan]

There is an item that can make these cars idle rough, use extra gasoline and at times cause black smoke from the exhaust when it fails. I have found it to have failed on about 50% of the cars I have owned with the 307 Oldsmobile engine. It is a Canister Purge Valve. If you are looking at the carburetor from the front of the car, the valve will be below the carburetor to the left. It is a black plastic control valve about 1 1/2 in. across with 4 vacuum hoses coming from it. 3 of the hoses go to the carburetor and one goes to the emission cannister through a temperature control valve. It can fail in several ways and can draw raw gasoline vapors directly from the vent chamber and send them into the intake manifold through one of the vacuum hoses. The valve can be checked with a vacuum pump.

There are some other ways to tell if it has failed. If the car is running, the hose going to the vent chamber may be cold or even iced up. You can remove this hose from the carburetor and plug it up to see if the car runs better. Another way to tell if it has failed is to remove the hose at the canister that goes to the valve. The car should idle and run better if the valve is the problem.

Autozone has these valves for $12.99. I always carry one in my tool box.

[sosuzguy]

Perfectly stated!