Rough Idle

**thacher2189** · 02-13-2012, 11:11 PM

1994 Camaro z28

head gasket had a small leak. Replaced both head gaskets, water pump and opti. Have everything back together now and I have what I think is a vacuum leak. When i start the car it revs to about 3000 RPM then drops back to a rough idle around 1000. Then when idling it'll randomly jump around up to 2000 and back down. Sounds like it has a mild cam in it. Brakes are really hard, like the booster isn't getting enough vacuum. I have replaced a couple vacuum lines on the manifold. Not sure what to do next, just runs like crap now.

**5.0THIS** · 02-14-2012, 11:57 PM

Something wasnt put back together correctly. Not much help I know, but it all has to be gone back over. Check all of your vacuum lines, all of the intake plumbing, and maybe scan the car and see what's happening when the car surges.

**chris1974** · 02-15-2012, 07:35 AM

Could it be a bad/dirty IAC or TPS?

**thacher2189** · 02-19-2012, 02:04 PM

I have it all back together correctly. My valves were too tight and it was leaking air internally. I adjusted everything right now and it idles at the right RPMs and all. However, it still idles rough and I think it is a miss. Whether it is my injectors, plugs, wires or ignition coil.. Im not exactly sure yet. I'm going to run a timing light through each cylinder using the arrow on the damper. I was just wondering if the car fires exactly at TDC for cylinder 1? I've heard that fires like 10 degrees before TDC, but I'm not really sure.