98savage

I've had a CEL P0135 "O2 sensor heater circuit malfunction (Bank 1 sensor 1)" and I just replaced the O2 sensor in the header, since that's what the code is for.

The sensor was purchased at Auto Zone, it is a Bosch and has the plug on it. So I plugged it in, put in the O2 sensor and still have the code. The battery was disconnected before I even took the old O2 sensor out.

The O2 sensor that I took out was completely white, so I'm assuming it's burned up. Nonetheless, there is a new one in there and it's still giving me the SAME code as it was before. So I have no idea what's up with it.

The only mods I'm running are CAI, header, test pipe, exhaust.

I was thinking "hmm, maybe the test pipe caused a CEL"....well, no, because it would've been a code for the 2nd sensor OR a catalytic converter malfunction or the sort. So I really have no idea....does anyone have a clue what happened?

98savage

Nobody knows...or has had this happen before?

hondadude

Voltage at pin 3 and 4 wire side when the key is on?

Resistance correct on the sensor side for the heater circuit?

LINK;
http://img139.imageshack.us/my...7.jpg

98savage

There is absolutely no voltage reading. I have no idea why. I have the wiring diagram in my Haynes manual but the colors are all different. I am just going to take it back up to the shop that did my auto to manual swap and have them jack with it.

tech8

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98savage &raquo;</TD></TR><TR><TD CLASS="quote"> I have the wiring diagram in my Haynes manual but the colors are all different. </TD></TR></TABLE>

The wire colors shown in hondadude's image corresponds to the OEM O2 sensor wires (white, green, black, black). You car's harness wires for the O2 will be different colors.

98savage

I wasn't talking about the colors in the picture. I was talking about the colors on my harness and the colors in the Haynes manual. They are different.

The harness coming off of the car does not get any power...when the O2 is plugged in, there is no fluctuation in voltage or anything. So there is something in the wiring that isn't right.

I will have to take it up to the shop because I can't figure out what the hell they did. I know which wire goes where on the PCM / ECU but I don't know the location. If that makes sense. They should know what they did, so back I go I suppose.

CARMandP

Do you have the ULEV ex model? It will say ULEV on the valve cover. If you have the ULEV, the autozone o2 sensor will never fix it because the ULEV engine takes a special O2 sensor that is dealer only and its expensive. Have experienced this on several occassions.

98savage

Nope, not ULEV...

Could it be throwing a P0135 for not having a cat? I could try the sparkplug non-fouler trick but it's not giving me any cat inefficiency code or low voltage or anything. It is strictly P0135...that's the only code I get and it's for the O2 in the manifold....but would a test pipe cause the code?

mug3naccord

dude i have the same problem as you do and still couldn't figure out. i think it's the test pipe too. i have the high flow cat. on mine so i'm assuming it's the aftermaket cat. convertor

98savage

But again....WHY would that cause a CEL for the PRIMARY O2 sensor? It usually throws a P0420 or P0430. And even if it was the cat, there should still be power going to the O2 sensor...it should still have a reading. Correct me if I'm wrong.