1984 "Oil/Choke" Problem!!!!

[Chev97fan]

I just purchased 1984 Buick LeSabre with 3.8 V6 with 101,000 miles on it and it ran fine for about a week. The problem it has developed goes something like this:

I warm up the car for 2-5 minutes, then drive down the road without any problems. It rides smooth and cuts through traffic like a knife through butter. This situation lasts for about 10-15 minutes, then the car's "dummy light" will come on, showing in bright red "OIL-CHOKE." ...The car immediately begins losing power and a clacking sound emerges on the driver's side of the engine. (The clacking reminds me of bad lifters in the decibels department.) It feels like its running on only 4 cylinders instead of 6, as it is supposed to do.

It takes up to 30 seconds then to go from 0-45 mph....Sounds bad, huh? It sure is! ...I've replaced the rotor, cleaned the cap (no cracks) and had the ignition coil tested, which passed.

Anyone know what my problem is?....I'd be forever in debt to your service. Thank you!!!!

[Mechanic_of_URL]

Correct me if I am wrong, but it sounds (to me) like an oil pump going bad, or the carburetor may have a bad gasket.

[public]

coils and plug wires can be heat sensitive. They may function fine when cold. I would start with a good tune up. Plugs, wires, cap, and if this does not do it then a coil. Also check your EGR valve, when bad they can cause detonation. Good Luck.

[avatar307]

I do believe that on the older cars that still have a distributer and rotor, and "tune up" involves new points, new plugs, new rotor, new cap, and new wires. Usually sold together in a "tune up kit." The wires would very likely be bad, especially if they are the originals.

The EGR Valve, just FYI, should be open when the engine is first turned on. EGR is Exaust Gas Recirculation. The purpose is to introduce hot exaust gas into the air intake to warm up the air and produce a more efficient fuel/air mix.

Once the engine is at operating temp, the EGR valve should close. If it does not close, it can cause the air to become too hot, resulting in detotations/misfires in the cylinders. (At least I believe they occur from the air being super heated when the problem is related to the EGR.) Those detonations/misfires are not only bad on the engine, but it would cause the power output to drop (like running on 4 cylinders).

I'm about positive your EGR valve is controled via engine vacuum. You may have a bad vacuum tube going to the EGR or somewhere in line to the EGR from the vacuum source.

Now I've never seen an "OIL-CHOKE" light, but I'm guessing it was a means of saving costs by combining too lights in one. The light likely means "your oil pressure is too low" and/or "fuel is being introduced into the engine faster than it can be burned."

With the engine not burning the fuel correctly, running on 4 cylinders instead of 6, etc, both of these conditions would exist. -- Your oil pressure would be low, because the engine is not producing enough RPMs/power to pump the oil effectively. -- Your foot on the gas pedel determines how much fuel is introduced into the engine from the carberator. With the engine not running at the speed/efficency it should be, the carberator would be dumping in more fuel than the engine could consume. Thus, you'd be flooding the engine, causing an "over choke" condition.

[buickmastermind]

Try spraying some carb-cleaner into the top of the carburetor. It seems like a carburetor problem. The choke is probably sticking, and you might have to take the air cleaner off, and clean the mechanics on the exterior of the carburetor, thourghouly cleaning and using a rust dissolving spray when neccessary. I have seen similar problems from a vacumn leak, pointing to the hose between the EGR valve and the carburetor/throttle. Not to scare you, but it could also be a carburetor gasket going bad, but that is not likely.

[mrmonsta2001]

I have the same problem w/my 85' lesabre the oil/choke light basically stays on sporadically while I drive. Took it to a transmission shop the mechanic stated that the engine has low oil pressure and that it's just a matter of time before the engine has to be replaced.