1987 cabriolet idles rough and will not accelerate

Karl, have you confirmed good fuel pressure? It sounds like a weak fuel pump to me. Is your Check Engine light on? If so what are the codes in the computer?

Removing and flushing the tank is the only sure way of cleaning it all out .

At that point, I think the best thing to do would be having the carburetor taken off, take it apart, put it in some gunk remover (Carburetor Cleaner sold in 1 gallon barrels), then wirebrush it all out, make sure all the jets are clean, buy a carburetor repair kit, and put it all back together with new seals. At how old your car is, it would probably be best for it. On the cheap side, all that needs to be done is having the carburetor's throttle accelerator pump fixed (Squirter). A shop should be able to do all this, but it's not hard, either.

I would check the fuel filter, which is under the car, below the passenger side rear seat.

heh, you might want to change the title here as I am pretty sure you cant idle under heavy acceleration.
However I think you were on the right track with the plugs and wires. You didnt mention the cap though and that is usually the biggest culprit in damp weather. Put a new cap and rotor on it and see if that doesnt do the trick.

search forna repair book at a parts plaace or online-a bad idle can be a number of things-from an ajust to a electrical tuneup-replacing parts without good info equals $$

large vacuum leak from mnifold

I just had the same problem. Replaced the fuel filter,still crappy idle and no acceleration. I replaced the fump pump along with the wiring harness and the fuel pump screen and my cars purrs like a kitten,has back to normal acceleration and idles better than before. Hope this is some sort of help to you. I did it myself. Total cost, a little over $120. Good luck. By the way, your fuel pump should be pushing out about 65 lbs of pressure. is it ???

I would suggest hat you replace the timing belt. The noise that you hear is the belt.

Check the hose between the inletmanifold and the pipe to the brakeservo it normally gets old and a crack in so the engine sucks false air on cylinder 4, causing engine to run rough or uneven.