Black plugs after head gasket

Chucks twr · 12-02-12, 08:31 AM

First post here, but not new to forums or wrenching. I searched this forum but didn't find any answers so here's the background:

'98 CL 2.3 came to me with a bad head gasket. After finding the head not warped using a machinist straight edge, I put the engine back together. started it up and it ran real rough and stuttered real bad if you tried to accelerate. Pulled the brand new plugs and they were covered in black soot indicating a real rich mixture.

I have verified the following: 175-180 PSI in all cylinders, cam timing is dead on, no adjustment for ign timing, valves are set .010in and .012ex. NO CEL and I am lost. Nothing that I can see disconnected, swapping back in the old rotor, cap and plugs made no difference. Any ideas? thanks for any help.

Hondacuraplanet · 12-04-12, 10:08 AM

Sounds to me like you've done everything right. Assuming that the timing is set correctly, the only thing we've got to work with is fuel mixture. In a situation like this, I'd assume that you'd be getting a check engine light, but even if not, check the EGR and EGR port passages for a clog. That's a very common occurrence with this particular engine after it's racked up some miles.

Chucks twr · 12-05-12, 08:08 AM

Thanks for the response. Well I went back after letting it sit for a day, and letting my frustration evaporate. Started looking and noticed 2 sensor plugs at the intake of the throttle body are different colors but the same shape. They both reached the TPS and what I think is the IAC, and the sensor colors were black and the connector colors were blue and grey. Anyways I switched them and all is good.

I still can't figure out why no CEL, but it is going home to its rightful owner now.