Hey everyone, just curious to know if anyone has run into this problem before? I'm in the process of changing the o2 sensors in the MPV seeing as the car has over 107k miles and the gas prices are starting to get a little crazy! Anyways, I replaced the one in the front bank about a week ago. No problems. I replaced the one in the rear bank (the firewall) drive the car around everything is fine. The next day the wife goes to drive the car and the check engine light is on. The codes read p0031, and p0134 reads as a pending code (whatever that means). It also mentions something about I/M monitors and I get hits on Catlyst, Evap, O2 Snsr, and EGR. Everything else reads ready.

The question is how long does it take for these four i/m monitors to read ready, and once they finally do, will that clear the other codes or do I have to do that manually?

Thanks for any help you guys may be able to offer, this is something I've never come across before.

 

Hi, did you have to remove the intake manifold to replace that rear upper o2 sensor? Or did you do it from below?

 

Update for anyone dealing with this. P0031. You do not have to remove the intake, although that is the "book" way to do it. It can be accessed from below after removing the subframe support (4 large bolts, 2 on each side). You have to reach around both sides of the exh manifold. It is very VERY tight to remove the connector. I'm not a huge guy, but if I was 5% more swole no way would my forearms have been able to do it. I got pretty stuck in there, with shoulders lifted off the ground. I suggest having your wife within ear shot with a bottle of lube, I am not joking about this. Also, the pre-cat o2 sensor connector is up there also. If you're getting both codes ( P0031 and P0037 ) it's a lot easier to replace both sensors at the same time.

You absolutely have to have the small crowsfoot o2 sensor socket.