My 1986 2.8l firebird is loping at idle and during acceleration, and when cruising at highway speeds. It feels kind of like its surging/loping and idle rpms bounce around by +/-200 rpms.

I just changed the drivers side manifold gasket, and had to remove the plug wires on that side, is it possible one of the drivers side plugs/wires is garbage?

What should I check first?

Thanks,

Jdvorsky

 

My car was doing the same thing. So, I changed the rotor,cap, wires, plugs, and cleaned the Idle Air Control Valve. I used Seafoam in the Intake Manifold. DIDN'T FIX IT...

Now I am changing the injectors, fuel filter, and cleaning the intake.

I hope your isn't as bad as mine...

 

I'd look at the tune up parts & replace them if in question. Firing order is 123456. #1 is at the front pass side, #2 is at the front drivers side.

 

When you did the gasket set, did it seal properly through there? If you didn't get it right, the engine will know....

 

Looked at the spark plug wires today after work and they were all garbage, 1 was sliced open and 2 broke taking them off.

So I changed those out and that fixed most of the problem, still idles a tiny bit rough but I think it was doing that before the huge idle+ driving problem happened.

 

Cam lope bruh