I had a clutch job gone wrong and ended up having to pull the engine and transmission as a unit. After re-installation, the car runs pretty well but has a slightly rough idle, a bit of coughing at low rpm starts, and a dash light for rich fuel. I've checked and double checked for anything unplugged or broken and cant see any problems. Any ideas on what could cause the rich fuel mix? I assume I must have made some error in the engine re-installation but I have triple checked on top and under the car and can't see any issues. Please help!