Hi, Ive been trying to figure out what's wrong with my camaro for a while. It tends to backfire when I'm decelerating and I've been getting awful gas mileage for a while (18-20 mpg highway). Also, the car has always felt sluggish at low rpms and I have driven a few ls1s before. I have replaced the pcv, both AIR check valves (one went bad and set a code), the front 02s, the fuel filter, the spark plugs, and I have just recently removed my cats to see if they were clogged, and they weren't. I did drive it for a couple days with them removed, and it did set the SES code for the front two 02s being disconnected, but not the rears. Also, now that I've put it back together, the SES went off for a couple days, but then came back. PO154 (insufficient activity bank 2 sensor 1 02) which is the same code it set when I had removed that 02, but also P0137, low voltage to the bank 1 rear 02. Thats interesting that it set a code for the rear 02 now that ive reconncted it (I assume it came loose for some reason) but not when it was still disconnected. Could there be something wrong with my computer? Does anyone have any ideas? I've been trying to figure this out for months! Thanks for your help

 

ttt

 

Check the wires on your O2 sensors to see it they are broken, melted, or scraped through.

 

Help me understand. Your front O2's are still disconnected, or not? YOu are getting a code for your rear O2's and you don't have cats?

 

try switching the bad 02 sensor left to right, reset your SES light, go from there. see if the code follows the potentially bad 02 sensor around.


EDIT: presuming the electrical connectors are the same... i think they are?

 

They are the same. Should not have any problems moving the sensors.

 

I have bolted the cats back up, they were only off for a few days. I havent had a chance to swap the o2s around yet, although I did check them and they all look fine. The front two sensors are only a couple months old, I just put them in. But its been getting bad gas mileage long before I did anything with the cats or the o2s, and I cnat figure out whats wrong with it.

 

If you still have the a.i.r. system, check the 2 check valves. I've seen them not seal correctly and cause symptoms you've described. If you pull the rubber hose off the end of one, you should be able to blow air through the valve, and not suck air back through the other way.

 

I'll have to look at that. I replaced both the check valves after one of them set a code (the code did go away afterwards)

 

Ok I finally checked the AIR check valves, and the rubber lines on the back were loose because of the crappy plastic clamps, and I also noticed that the passenger side valve had a bit of rust on the end of it. Should I replace it again? its only like six months old. I havent noticed any improvement in mileage however.

 

ttt