I have fuel trickling out of the throttle body (plenum chamber) into the air cleaner inlet hose--enough to fill the corrugations and then overflow onto the engine. I rotated the butterfly dampener valve and was able to view gas trickling down. Any thoughts on what the problem is, and how to fix it, cheaply.(!)

Welcome to AF, check for fuel in the hose to the fuel press. regulator, for starters. BTW, do not run the engine like this, as by now the fuel may have contaminated the oil.

Thanks for the welcome AND the advice!

I disconnected the fuel pressure regulator vacuum hose, and fuel indeed is coming out. I also disconnected the vacuum hose assembly to the throttle body, and it is evident fuel has been passing through the line that connects to the fuel press regulator.

I am always open for 2nd opinions, and would like to know if you agree w me that the fuel press regulator diaphragm needs replacing. I'd like to limit my disassembly, so I await, and hope for, your confirmation.

TIA!

The regulator diaphragm is bad, replace it and change the oil and filter.

Thanks again!

I couldn'g get the diaphragm by itself, so I am going to replace the entire fuel pressure regulator. I'll let you know how it turns out.

I'm very impressed by this website!

After some delays, I am glad to report that all is well with the Olds. this was my first repair since acquiring this car, so I had a little learning curve to adjust to. There are some strange quirks, such as rotating the motor, but nothing too difficult. Admittedly, I understand why mechanics charge what they do.

I would never have been able to pinpoint this problem without your help. The Haynes manual and a 1990 Chevy Lumina (same motor) service manual were pretty inconsistent and extremely vague. I would have been very disappointed if I actually bought these, especially the factory service manual--what a joke!

Thanks again for your help!

Good results, glad to help, those manuals are basically useless, an online subscription to alldata.com is a much better way for anyone.