Hello everyone,
I just finished replacing the valve cover gaskets on my, original to the car, 350 small block with the original quadrajet. I used Fel-Pro non-cork gaskets. After I was done, it fired right up and idled great.

Yesterday, I took it for a long ride. Again, it fired right up and ran great. About 15 miles into the ride, I stopped for coffee and when I attempted to back out of the parking space, it stalled. It fired right up, I put it into reverse and it stalled again.

From then on, whenever I had to stop ie red light or stop and go traffic, it wanted to stall when I hit the accelerator.

I meticulously documented, with pictures, the disassembly so that everything went back where it belonged.

I didn’t adjust the carb in any way. I did have to replace the carb choke heater connector because I broke the old one but I can’t imagine that that would have anything to do with the problem.

I can’t understand why the problem started so far into the drive, I would think that it would have started as soon as I started the drive if I had made a mistake putting it back together.

It’s a 1981 L81 that’s all stock with the exception of the exhaust system.

Thank you for reading my post.

 

When issues arise after heat is introduced, sometimes its a module. But when modges get hot, they usually shut down for several minutes until cooled. Yours did not do that.

Fuel perculation is a common issue on C3s in the summer heat. The fuel gets so hot it actually boils out of the carb, via the bowl vents. There are a few remedies to correct this if that is the problem.

Next time your event happens again, pop the lid off the air cleaner and see if vapor lock is taking place. These types of issues are hard to track down.
But my money is on the carb.

Good luck

 

Thanks HeadsU.P.

How do I determine if vapor lock is taking place, what am I looking for?

 

Fuel will bubble or percolate out of the bowl vents. Will look like a old style coffee maker.
Obviously a dangerous situation with gas boiling over and on down to the Intake.

If hood clearance is not an issue a insulating spacer between the carb and the Intake carb pad help immensely.
Other tricks are blocking off the heat cross-over under the carb.
A heat shield under the carb.
And making sure your fuel return line is intact and operational. That system in itself makes warm fuel return to the tank for cooling, then pumped up to the carb again.

 

I may have found the problem. I check the vacuum lines as best I could and they appear to be fine.

I removed the EGR and it appears to be stuck open. I spray it with carb cleaner and let it soak, the plunger wouldn’t move.

I install a new on and she fired right up and idles good but I haven’t taken it for a long ride because it won’t stop raining.

I’ll keep you posted.

This the underside of the EGR, it looks like there’s carbon buildup inside there.

 

Thanks for the update...it will help someone with the same problem

Rookie question to members: Is the EGR valve REALLY needed (other than GM thinks so)?
In the old days my friends would remove/block the passage off on their engines.

 

Short answer: No.

 

smog zealots answer to nox emissions.
new engines, ls base, use cam timing to achieve the same thing.
if you don't have smog test req'ts them block it.

 

The problem has been solved…it was the EGR valve. The rain finally stopped long enough yesterday to take it for a long ride to Rockport, Gloucester and Newburyport and the car ran great. No hesitation at all.

Thank you to everyone who gave suggestions of where to look for the problem.