It has been idling very low, feels like it about to die at a stop in D position (after driving it for a few minutes). The check engine light is on (P0135 Primary Heated Oxygen Sensor- thats what the pep boy got told me after runningh his scanner).

After further inspection, looks like there was some oil seepage through the cycliner head on the left side where the distributor connects to the cycliner. Over the weekend me and the old man work on replacing the head gasket and O-ring. No leaks today and thought we might have solved the problem. However after test driving it for a longer period of time. The idle is still low and it actually die at a light today. It does restart and I can drive it home.

Any guess as to what else might be wrong?

Update:

found out there's a big crack in the manifold

TIA

 

It could be your IACV = IDLE AIR CONTROL VALVE

 

ok I take a look at it. A friend of a friend told me if might be EGR since CEL is on.

any thoughts?

 

do you have a cel code?

 

yes P0135 Primary Heated Oxygen Sensor

and after some more googling. I think that might be the culprit. I'll replaced it on Wed. I'll update this thread once I've completed the job.

thanks Civic

 

Cleaning the IACV is a routine maintenance task, they do get dirty. But resolve CEL codes first. You can check the sensor heater with an ohmmeter. Engine cold, unplug sensor and measure resistance between the two wires that are the same color. If it's open circuit, sensor needs to be replaced.

 

My 2000 LX has the same low idle due to a primary O2 sensor. Been driving it for months. Idle gets a little low, but a trick is to turn the AC on (low). Just adding the extra load to the engine makes it kick the idle up enough to not die.

 

I was replacing the o2 sensor and after opening the manifold cover, I discovered a big crack. Looks like I'll have to replace manifold too. Check prices online and they all the OEM manifold comes with that "flange?" I couldnt find one without it. BTW I did have to buy the CA legal manifold and that cost even more.

I will replace it this saturday, any tips is appreciated.

 

So i got the new exhaust manifold installed. Replaced both primary and secondary o2 sensors.

CEL is off now but car stalled on me again during a short trip.

I've been told that it could be a dirty EGR or something with the PCV. I am not familiar with any of those. Anybody have experience with cleaning or placing these parts?


TIA