Battling 1222 code on M42

[tander05]

Hey guys,

Just did some suspension/drivetrain work and had the exhaust dropped for about 2 months and put a bigger master cylinder on the car.

Ever since I put it back together, I've been getting a rough idle and a CEL for 1222 only on idle. Almost sounds cammed or like a rotary. Any blip of the throttle and the code goes away.

O2 sensor is about 1 year old and thought it might be a vacuum leak so I looked and found many torn hoses and replaced every vacuum line/hose under the intake manifold.
Car still idles exactly the same and CEL still there. No loss of power or anything problems once I get in gear only at idle.

Any help would be great!

[roguetoaster]

First off, make sure the TB plate appears seated at 0 throttle.

Look at your TPS wires. Consinder replacing the O2 sensor just in case it was dropped and broken, although you can test them easily enough.

[tander05]

So the same day I unplugged turned the car on and then plugged back in the 02 sensor after turning it off again. Then the car ran perfect again. Drove it for 2 more days. Short trips. Now today I drove about 20 minutes filled up at a gas station and then sitting at a light the CEL came back on and started running funny again. Better than before but still funny. Now I got home and am getting the CEL very consistent now.

[tander05]

I notice that i get no CEL if the 02 sensor is unplugged but a CEL when it’s plugged in.

[turner.e30]

If everything is fine when the 02 sensor is unplugged, check the wiring harness against the front firewall in the engine bay. There's a connector up on top of the wiring loom (behind the plastic cover) that should be unplugged if you're running an 02 sensor. If it's plugged in, try disconnecting it.