I have the following two codes. I searched on this board and no one has seemed to find a fix for the codes.

P1133 Heated Oxygen Sensor (HO2S) insufficient switching Bank 1 sensor 1
P1153 Heated Oxygen Sensor (HO2S) insufficient switching Bank 2 sensor 1

It's saying the my front O2's, both of them, have insufficient switching.

Things I recently did. MAC midlengths, and catback, New plugs, one O2 extension on drivers side, PCM tune from www.madz28.com.

I just put the new PCM tune in yesterday and have about 80 miles on the new PCM tune before the code came on. I was cruising about 75 mph when it came on.

All spark plugs wires look fine. All wires look good.

I did use a fair amount of Copper RTV on the header gaskets and the collectors. Could that contaminate the O2's? I think it says on the Permatex tube that it is safe for O2's though.

Anyone see this before and fix it???

Thanks,
Dan

 

my book says possible causes could be wiring-maybe melted on new header or pins bent in connector? exhaust system leak? last bad o2s. I would take a very close look at the wiring.

 

Thanks! I'll triple check the wiring. It kind of makes sense. I don't know why both O2 sensors would all of a sudden go bad in about 80 miles of driving.

The only way I see that being possible is if the Copper RTV burned off the inside of the header gaskets and fouled the sensors on both sides.

Thanks again. I'll look into that.

Anyone else have the problem and fix it? Any thoughts?

Dan

 

Well, I checked everything I could. No burnt wires that I could see anywhere.

No bent pins.

I disconnected the battery and looked at the PCM pins and they all looked good. The SES light is off now, but I don't doubt it will come back.

No blown fuses... Car runs good.

I'm going to buy some heat shielding for the wires that run along the fender well on the passenger side. They are about 5/8" from the primary, but didn't look burnt or melted at all.

Just wondering if anyone had this problem and found the silver bullet.

Dan

 

Solved the problem the other day.

Just in case someone searches for this problem in the future, I did find out that it was just that the O2 sensors needed replacing.

It's running awesome after the new O2's went in.

I think one of three things killed the O2's.

1) Inside coating on the headers curing from the hot exhaust gases just after getting installed and fouling the O2's
2) Ultracopper RTV baking off the header gasket and fouling the O2's
3) My exhaust leak caused me to run very rich and foul them. I fixed the exhaust leak.

I made sure to run about 200 extra miles after I got the code in the hopes that any baking/curing would be complete by the time I put the new O2's on.

So far so good. Simple as two new O2 sensors. Go figure, the code was correct.

Dan

 

thanks for the update! It's so nice when some post their closure to a problem!