Hey guys, car is a bone stock (other than lid and muffler) 99 Formula. 218k miles, and runs perfect.

A while ago i was chasing a p1153 code. After replacing the o2 sensor (which didnt solve the MIL) i found a vacuum leak in the pcv system which seemed to fix it for a month until today. Today the MIL popped up intermittent for p0122 (tps) and intermittent p0161 (o2B2S2), and my current codes were , p0430 (b2 cat efficiency low) and p1153 (o2B2S1) all at once. Both upstream o2 sensors have been replaced with densos from the previous p1153 code, they maybe have 200 miles on them. I also have an egr code ive had ever since i bought the car (doesnt indicate the MIL according to the scanner im using)

Recently i got under my car trying to find an exhaust rattle which turned out to be the inside of my driver side cat rattling lightly. The passenger cat made no noise.

Anybody dealt with this before? Would a bad/clogged cat cause an upstream code? I assume the cats are original.

 

driver side rattle cat this done **** been broken inside

 

Care to put that in English??

 

Just a small update. I cleared the codes and now im only getting the p0405 egr code and the p1153 b2s1 code. Could a clogged cat, or a bad rear ow sensor cause my front o2 sensor to be slow responsive?

The bank2sensor2 code was intermittent along with the cat efficiency code which are now both gone (for now)

 

Just another little update. For anyone that may ever have this issue. Ive realized a lot of problems threads have no ending.

After more miles and a day of running the car semi-hard my p1153 code has gone and has been replaced by the cat p0430 code. Exhaust shop appointment monday. Cats have gradually gotten louder rattling now when cold.

 

Rock auto.. Best general prices I've been able to find on cats.. If you want stock.
I had the guts of one melt down and plug the pipe.. That will end your day..