I had my timing belt,tensioner,idlers,water pump,front seal and cam seal changed on Monday. (97 leg wagon 2.2 152k) Yesterday on my way home from my parts car my cel came on. I went to Autozone and had the code checked. It was the almighty PO420. I've been searching the message boards and found lots of stuff on this code. On one of the boards I read oil or coolant leak. Is there anyway this code is related to my timing belt swap?? It seams to be running fine and I've checked all the vacuum hoses a couple of times. No major leaks anywhere. Does the old disconnect you battery and run the system dead clear the code on a sub? I've never had to do it on an ODBII.

Edited February 17, 200917 yr by korrupt66

http://www.obd-codes.com/p0420

I don't see how a timing belt job could cause a 420 code. It's probably a coincidence that it happened at the same time. I know the 2000 and up cars had trouble with the cat actually failing, but most of the 420 codes I've heard about on the older cars were caused by the oxygen sensors getting old and slow. It's probably time to replace both of yours.

 

On the OBDII cars, you need a scanner to clear the code.

Well I cleared the code yesterday. I've put about 50 miles on the car and no code yet. I'm holding my breath to see how long it will last. Thanks for the help guys.