Log in

View Full Version : Honda civic runs rough.


PRPPRIMO
Aug 24, 2008, 09:19 PM
All right, this is for the more experienced technicians as I have some under my belt. TXGM, I would like your 2 cents on this as well as others that care to post their knowledge. The engine starts but idles rough and revs slowly with very little power. Plugs/wires/distributor replaced. Compression and fuel pressure checked out OK. (120-150 psi compression & about 35-40 psi fuel pressure) Further symptoms include fuel in the engine oil & oil/fuel out of the exhaust (fairly large amounts). Which to me are common symptoms of both a stuck open and stuck closed PCV valve, as well as worn valve guides.

I believe if it were a faulty head gasket or rings, I would not be getting the mentioned compression from the cylinders. Not certain that simply replacing the pcv valve would correct this. What are your thoughts?

TxGreaseMonkey
Aug 25, 2008, 06:24 AM
Assess each cylinder, by "reading" and smelling the spark plugs. One or more plugs are likely not firing. Check for a good spark at each plug. If necessary, consider replacing the ICM and coil. This likely accounts for the unburned fuel. A faulty Engine Coolant Temperature Sensor could also be a contributing factor, allowing too much fuel to be injected.

I suspect the valve guides and seals need replacing. This likely accounts for oil in the exhaust. The PCV Valve, which is super simple to replace, is not the real problem.

PRPPRIMO
Aug 25, 2008, 06:46 AM
All 4 plugs drenched with fuel. Swapped distributors from another civic that runs perfectly just to rule it out. It appears it is time for a valve job.

TxGreaseMonkey
Aug 25, 2008, 07:00 AM
I agree.