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Problems/Service/RepairsIf you have a problem with your HHR, want a tip on repairing or performing a particular service to you HHR here is the place to post!
P0420= dead cat! I found out the hard way with my 2007 2.2 automatic.
the P0171 it had was from the cracked flex pipe.
A new catalytic converter fixed both problems and was only 5 fasteners! Plus the O2 sensors, easier to remove on the ground , you can disconnect them from the top with the air box off, and the three exhaust manifold nuts.
P0420= dead cat! I found out the hard way with my 2007 2.2 automatic.
the P0171 it had was from the cracked flex pipe.
A new catalytic converter fixed both problems and was only 5 fasteners! Plus the O2 sensors, easier to remove on the ground , you can disconnect them from the top with the air box off, and the three exhaust manifold nuts.
do you think it's possible to get at the rear 2 bolts with the car on the ground or not enough leverage/clearance? (just assuming the freeze-off and pb blaster has made them easy to turn.
I just want to try to be as covert as possible as my condo association doesn't allow people to work on their cars - or should i say, only if someone sees you and complains. i've managed to do other work on cars in the past without getting into trouble but it was always stuff that didn't require lifting car up on jacks. That gets to be a bit too obvious. Although i did have a car i was parting out in my space that i put a cover over. Of course one of the first things to sell was the hood... not a big deal until the wind blew the cover part way off the next day - now THAT looked bad... still, no one complained.
the upstream O2 sensor isn't on the cat on the 06 but just off the manifold - i bought a special O2 socket https://amzn.to/3Ja4xwN and can't seem to get it to go down onto the nut - pic isn't the best i know - i've tried rotating the socket slowly around trying to get it to seat and no dice. I thought maybe something is keeping it from going further down onto the O2 nut but i can't figure it out. Thought this was going to be the easy part.
Also, after pb blaster/freeze off had done its thing, the 3 nuts on the upline cat were easily removed - tested a rear nut while car on ground and was able to get it to break free too (still waiting for a good time to jack up the car proper without neighbor interference.
The new cats all come with replacement nuts AND bolts - but the bolt stems on the original have no head to them - should i just try to reuse the old ones or is there not enough 'wiggle room' to get the old cat off and new one on with thsee bolts protruding at both ends? IF they should be taken out, any tips on how to go about that? Thanks
Your pic does nor resemble the link. Have you tried it on the new sensor? Might be the wrong size.
The bolts on the header are studs with reverse Torx heads. If they stay in reuse them.
The other end has studs welded on, you can drill them out and replace with stainless steel nut and bolt.
When I twisted a stud off I just went to the hardware store and got a bolt of the proper size (metric thread), because studs are a real pain to R&R.
