car lost power and RPM drop and car stalled

[eddie]

Hi,

 

I am new to this site and I need help.

My Opel Manta GTE2.0 coupe runs fine for over 30 years.

Now there is a problem. when it runs for about an hour, the RPM will flicker quickly and the RPM drops and finally the car will stalled. However, if I wait for a few minutes and restart the car, it runs smoothly again.

What do I need to do.

 

Thank you,

Eddie Goh

Singapore

Manta owner since 1980

[moodoo]

Hi Eddie,

I had a similar problem with my engine a few years ago. It would run fine for a while, then start to cough, splutter, and the engine would die. After a few minutes (maybe 10 or 15) it would restart, and be OK again, but the problem could happen again a short time later. 

It turned out that the wiring to the fuel pump was damaged, at the connector where it goes into the pump. It meant that instead of all the strands of wire carrying the current, there were only 2 or 3 still connected. So those pieces of wire were getting hot, resistance was increasing, and eventually the pump couldn't draw enough current, and the car would die. Once it stopped, and the wiring cooled down, it would be OK again for a while. 

Another thing that someone suggested to me at the time was to check the pick-up filter in the fuel tank. If it were sucking dirt, the filter could get clogged. Once the car stops, the dirt could tend to fall away from the filter and back into the tank. Then it could get enough fuel to restart, until again the filter became clogged.

Also, check the ignition amplifier. It is mounted to a heatsink in the engine bay, and there is supposed to be some heatsink compound underneath it. Eventually the heatsink compound dries out, and the ignition amplifier can overheat. I guess maybe this could produce a similar failure to what is happening yours?

Hope this helps...good luck!
Fin

[cam.in.head]

I was going to say ignition amp too or associated wiring to and from the coil paying attention to the green wire that also feeds tacho. Any issues in this area especially shorting the green wire to earth would cause the tacho to flicker as it is this very green wire that the tacho reads from. Fuel starvation however woukdnt make the tacho flicker ,more a gradual fall off of revs / hesitation .

[Shug]

I had exactly that problem. Was ignition module overheating. As fin says, Make sure its securely mounted to aluminium plate and has heatsink compound applied.