Hi all, just failed my emission test with a P0135 error code. Says O2 Sensor Heater Circuit.

trouble comes when I tried buying a replacement sensor before. I'm not sure if I need the upstream or downstream sensor that appears to be available on most sites.

I know Autozone is not the preferred place but I was in a pinch and they claimed to have one in stock.. That one they sold me had four wires on it, mine (If I am looking at the right sensor, passenger side exhaust manifold) has five wires on it.

Anyone know if I am even looking at the right sensor? I have a 2001 A4 1.4t Quattro

 

Take the sensor back to Autoblown , get yourself a Bosch 17090.

 

That code would be for your pre-cat or B(ank)1 S(sensor)1 O2 sensor. It's likely the folks at Autozone sold you a sensor for the older narrowband set up. I second M5S5's advice to take that one back and pick up a Bosch replacement. ECS tuning has pretty good prices on O2 sensors, and you might also try Rock Auto.

 

awesome thanks guys. The 17090 looks like exactly what I need. Even has the correct amount of wires Go figure

No mas AutoBlown! ! !

 

currently shopping O2 sensors myself due to the fact that I'm scheduled to fail my emissions test this Wednesday. Seems like right now the Bosch universal 4 wire on ECS is the cheapest at $53.31 each. If you get the universals you do need to solder and shrink tube the wires to your existing connectors.

(someone chime in if how I think it's supposed to work is not how it works. Please before I try to half-*** cheap my way through emissions testing)

 

Personally i like to get the sensors with the factory connectors. In your case they should be 16422 or the 16132 for the fronts. Some do require a swap of the pins from one connector to another.

 

I tried getting one of these cheaper ones myself.. The odd thing was mine has five wires coming out of it and these universals only have four. I really didn't know enough to determine if this was the right one or not so I took the advise of the guys above and bought the Bosch one they suggested. Local Napa had that one in stock for the same price ECS did $111 and they will have it for me this morning.

 

So I installed the proper O2 sensor. sure does help getting the right part from the right source! Thanks for the input guys!

I don't have access to a scanner to clear the codes, so I drove it for about 100 miles yesterday and the check engine light was still on. Kind of figured that would happen. Disconnected the battery for about six hours and when I re-connected it the check engine light was off.. At least till I drove about four miles, shut the car off and when I started it back up it came back on.

I'll try and stop somewhere tomorrow and see what codes it is throwing now, but out of curiosity, should the computer reset itself (check engine light) after it drives normally for xxx number of miles or days? Or is my only option to have a garage with the right scanner clear the codes after the new O2 sensor was installed?

 

Trouble Diagnostic codes,NEVER clear after any duration,even if you disconnect the battery,they will remain in the ecu,FOREVER...unless you clear them with a vag-com or other scan tool.

 

^Correct. Disconnecting the battery terminals will get your CEL to go away in many cases, but the trouble codes will be stored until properly cleared. If your CEL came back on after 100 miles, its possible that it came on for a reason other than the O2 sensors you replaced. Would be a good idea to get it scanned again to be sure.