RE: '86 coupe, tapping under car
 

Here's an update on the "tapping" problem. I replaced the fuel pump, pulsator, and strainer. Still have the tapping noise.
Two questions: I bought a new fuel pump relay. The Chilton manual doesn't tell me where the relay is and I really don't want to dig around looking for it. So: can anyone tell me where the fuel pump relay is located on the '86?
Second question: I am going to set up a pulse dampner for the fuel return line. Does anyone out there have a car that had had TSB #86234 done to their car?I'm looking for more info/photos about how Chevrolet fixed the problem. Also, does anyone know of a generic pulse dampner that might fit this type application. Jeg's and Summit don't seem to have anything like this.
Thanks,
Ed

RE: '86 coupe, tapping under car
 

Fuel pump relay is one of the relays next to the master cylinder. Still haven't cured your tapping noise? Does it do it at idle? Can you put it on a lift and listen while it is running?

RE: '86 coupe, tapping under car
 

Did you govern your fuel pressure down a bit?

RE: '86 coupe, tapping under car
 

Found the relay - thanks.
I did reduce the fuel pressure prior to installing the new pump and pulsator. It didn't make a difference.
I drove the car quite a bit for the last two days. When cold, the tapping is still there. It goes away when it warms up.
I think I'm going to try to do my own TSB on the car. Just need to find the right filter/accumulator.
I'll keep y'all updated...
Ed

RE: '86 coupe, tapping under car
 

I'm far from being an expert but it still sounds like a bad exhaust gasket (if they even exist today) they were nick named "donuts" they would make a ticking sound until the car or manifold warmed up. Think about it all the fuel line stuff you checked, shouldn'tbe effectedby warming up.

RE: '86 coupe, tapping under car
 

Read farther back up this thread, we already discussed that. But thanks for the input. :D

RE: '86 coupe, tapping under car
 

I have an 86, and it does the same thing. Someone told me once that it's the pulsator in the tank, but It wasn't worth the effort to pull the pump and see.
another person told me to put a fuel filter in the return line at the tank, and it would go away. haven't done that.
It only happens in winter until the car is warmed up to approx. closed loop about 160 degrees. it's annoying, but it goes away!