WTF?!?! O2 Sensors?? Broken Wire
 

I just finished putting the engine in my wife's 00-6. Everything went like a dream, (I even only bled from a half dozen spots on my hands!) Anyway, once in, I ran a bunch of carb cleaner through the intake, and t-body. Other than that, nothing else was done. Now I am getting two O2 sensors giving fault codes. Can the carb cleaner ruin them? I pulled out three of the four (the three easy ones) and cleaned them, burnt them and re-cleaned them, as I have done in the past on other vehicles, to no avail.

Could I have pinched a wire in the harness installing them? Any other ideas? Is it common for four to go at once???

For a little history, I pulled the engine with the thought that I had bad main and rod bearings, only to learn that it was spark knock. I replaced the engine, changing all the fluids, engine oil, coolant, and trans oil, spark plugs, and as I stated earlier, everything went together excellently. I am stumped on the sensors, and I really don't want to change out any, only to get the same codes. This car only has 90k kms (56k miles) on it and I don't see the sensors all needing replacement. Especially since when there was an ignition issue, they weren't giving codes.

Please help, I want to sell this car, and am not letting it go until I am sure that it is in great working condition.


OK here are the actuall definitions that my DTC reader give

DTC's:
P0141- O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0161- O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)

Pending:
P1036 (P) - O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P1056 (P) - O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)

Now if these O2 sensors are anything like the ones I had in my '96 F150, if you fart inside the car, it can kill a sensor. But do the above codes suggest something else?

Did you write down the code discriptions correct? Looks like its only the 2 secondary sensors that are causing the problems.

Yes, I copied them word for word from the book I have. The scanner I use is a cheap one, but it gives me an idea of the cause. (It's a Autel Geniscan GS300)

Sorry about the confusion regarding the number of sensors. I originally posted that all four were not working on another site, and copied and pasted it here, from a lack of responses on the other site, but that code has since disappeared. Now it is only the codes I posted above.

Would you suggest bad sensors or a broken wire/circuit? I thought upon install that I had the wires slightly pinched, but didn't feel that I had enough pressure to go through the protective loom (the big harness on the intake).

Thanks for the quick reply.

Codes is one part to deal with but the next thing I would do is install a scanned that can view the voltage #'s. Problem is not everyone had access to a scanned that can view the voltages. It is possible to do it with a voltage meter if you know what wires are for the heater circuit and the signal circuit.

Have you checked all the fuse's under the hood and in the vehicle. When you say "00-6" do you mean 2000 V6?? I might be able to get you a wiring diagram

You are correct, 2000 V6. If you have a wiring diagram, it would be appreciated. What are the voltages supposed to be??

This is the discription from Mitchell Repair

Still looking for the Heater Voltage......

Looking for a wiring Dia.

I will have to wait till I get home to privide the diagram cause Mitchell won't let you save their images. I will print off and scan at home

Here are the diagrams...Thought they would have been clearer. Hopefully they are able to help you.

http://www.machwon.com/ExtraStuff/Wire 1.jpg

http://www.machwon.com/ExtraStuff/Wire 2.jpg

http://www.machwon.com/ExtraStuff/Wire 3.jpg

The O2 sensors are shown on the 3rd page.

Thanks!! I'm going home to try to test these.

BTW Bitchn set of Stangs! (I prefer the '70)

Thanks

Hopefully the diagrams help.....

New question.

Looking at these diagrams, there seems to be two sets of wires that join..
13,14,15,16 GRY/RED on page one and 23 RED/YEL on page three. Would that not be a heater circuit, power and ground? The reason I ask is I went and purchased a pair of O2 sensors last night, plugged one in and still the same codes come up:
P0141- O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0161- O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
I am curious, do I need to replace both for it to work? Does the fact that it runs a common wire for something, constitute two new sensors?? I hate to add a second one, and find out it was not the problem. Once I install them, there are no returns.

Any thoughts? I thought I'd ask, as you seem to have decent knowledge (and a Mitchell manual which is expen$ive) at your disposal, and wonder if you've ever come across this.

BTW, Which is faster?

Have my money on the 70 in a quarter, but the 04 in an eighth.

Ever timed them at the track?

Installed the second one, no change. I plan to check continuity tomorrow, on all the wires. That will tell me for sure.

Looks like you have no choice now then to trace the wires. To bad you installed the 2nd O2 sensor. The wires that are connected in the diagram you can test from one O2 Sensor Harness to the orher O2 sensor harness. The others you can go from O2 to the PCM. Hopefully you find a break in the wire somewhere. Doesn't look like a signal ground is used for the 2 rear sensors but I'd double check the grounds on the motor to make sure you re-installed them all. Do you have access to a better scanner that would read the voltage readings without cutting into the wires? Snap-on or OTC are decent.

There is a fellow who is interested in buying the car, taking it to a mechanic tomorrow for an inspection. I am hoping that they have a better scanner, one that reads voltages. If nothing, then I am tracing wires.

As for ground wires, I agree, it could be easy to overlook one, as the car has nearly ten sepparate ground straps! One might think that the electronics were built like Lucas- positive ground............LOL!

As for the sensors, I pulled them both out and cleaned them up. I bought them from CTIRE, and they take back most anything, so I'm crossing my fingers.

I am guessing the scanner isn't going to read much but it would be nice to know. Kinda guessing its a bad ground or that harness that you think may have been pinched got pinched. Problem is if it was a bad ground you would think it would be effecting other items. Any chance a wire could have got caught between the trans and the engine?? Thats quite common due to lack of space and not being able to see that area.

No chance. I put the transmission on the engine before installing it in the car as a comlplete unit. I had them both out, so it was the logical choice. I figure it will just be a long arduous task, to find a bad wire. I am good at tracing wire faults, which means I have done it enough that I really don't enjoy it at all.