Famous p0172

Is the voltage the same with the light connected?

 

Nop. It drops when i connect the light

 

So it really seems like a corroded wire or a bad connection, guess it's time to start examining the wiring between the PCM and O2 sensor for any suspect areas.

 

Ok. Ill have to disconnect all the wiring and follow it trough until the o2 sensor. Can i use it with that code on? Wouldnt hurt the engine the o2 not reading or the system too rich?

 

Shouldn't need to unhook much to do a visual inspection of most of the wiring, I've found alot of wiring faults with a simple visual inspection for any spots it could be rubbing on something, damaged, or evidence of a previous repair.

As far as driving it the heater code wouldn't really concern me but the rich condition could possibly cause issues.

I really want to get the O2 heater working properly though to rule that out as a cause of the rich code.
Once we get O2 sensor working properly if we still have a rich code then we'll tackle that.

 

Ok thank you. Ill try to check i had the engine rebuild and had the wiring handy to check but never did this tests before. Ill have to check it on wednesday. Gonna use it to work tomorrow and wednesday morning and than stopping it again to check the wiring.

 

Did all this happen, before, immediately after the rebuilt engine was installed, or sometime later?

 

I bought the car from an auction came with a dead engine. It wouldnt turn it had a crankshaft bearing stuck.

 

Ahh the fun of having no history on a vehicle.

Did these codes pop immediately after getting it running or was it some time later?

 

It had a bunch of codes more. Had to replace crankshaft and camshaft sensor and vvti and bunch of other stuffs. Only problems remaining are those 2 codes.

 

So you have made progress.
We'll get it figured out, it may take us awhile but we'll get there.