87 GTI running on three cylinders

I have a 85 GTI golf with a 1987 16 valve motor swap. I think it is running on three cylinders. The car as no acceleration/power if I give it gas! It sparks out of the tail pipe and smokes if you try to give it gas. I can only do 40 miles per hour.

I checked the timing and it is dead center.

I replaced the catalictic converter hoping that it was clog however it is still doing the same thing.

I have taken it to 2 different mechanic and they cannot figure it out! Saying it might be a computer problem or fuel injectors!

Help - Does anyone know what it could be?

Sparks out of the tailpipe? Do you mean backfires?

Sparks out of the tailpipe? Do you mean backfires?
yes thats it

Backfires are usually caused by a bad distributor cap or rotor button. The spark goes to the wrong cylinder. I would try that first before moving on to more complex issues.

when you first start it up for the first time in a day how does it run?

if it runs ok and then goes to crap, check your coolant temp sensor. this will cause it to run really rich, and not run at all. on your engine it might look like there is a 5th injector off the intake manifold. that is for the cold start. what it does is when it is cold it puts in fuel to the intake acting like a choke until the engine starts to get to a certain temp. once it gets to a certain temp it shuts off. if it is faulty it will either not work at all or just shove in too much fuel constantly, possibly causing backfires, and a ton of black smoke coming out the back, hard idle, you rev the hell out of it and it doesnot want to go...... it can be a bitch to figure out. also what are you running? CIS, Motronic?

my car did something similar.

do you have a Bently Manuel?

Backfires are usually caused by a bad distributor cap or rotor button. The spark goes to the wrong cylinder. I would try that first before moving on to more complex issues.


We figured it out! It was two spark plug wires that were on backwards which caused it to miss fire. The car is running but screaches while driving. It sounds like the pulleys are touching and I tighten all of them but it still makes the screaching sound. It will have to do for now!

Thanks for all your replies!
Mystery solved!