Oxygen Sensor Codes: Misleading

[imp]

2004 Exp. 4.0L Flex Fuel, 5R55S, 153K. Recent serious issue ABS Module causing "Forced Limited Power". Replaced Throttle Body as no ABS codes detected. Same issues: flashing 4X4 HIGH light, ABS on, BRAKE on, then after several miles, Wrench on, then Limp Mode. NO CEL! Replacing the ABS Module with a used one got rid of all trouble except ABS light constant on, DTC "VIN Mismatched". Test driving this way, maybe 5-10 miles, CEL came on, checked DTCs: "HO2S Heater Resistance Bank 1 Position 1; HO2S Heater Resistance Bank 2 Position 1".

Yanked out all 4. Heater resistance specs. call for 3 to 30 Ohms, upstream were both 5 Ohms, Downstream 9 Ohms. Within spec, original OE parts, 153K. Ordered 4 from Rock Auto, O'reilly wanted $90 each for Bosch, I got Walker all 4 for $111. Not sure about Walker, but threw them in this afternoon. Hands a mess of bleeding cuts, damnedest locations for sensor plugs, but I vowed I would NOT lower the transmission rear to gain access: Cross support for gas tank less than one inch below driveshaft!

Now, the Ford trouble-shooting step by step does all harness wiring integrity checks first, from PCM to sensor end, a huge amount of messing around with long leads of Ohmmeter wire, etc. I gambled on the high-mileage sensors. Drove it about 10 miles, no CEL. ABS on. Tomorrow I'll take a longer trip. My wife refuses to go along, says I'll need to call her for a bail-out!

Anybody know which sensor, upstream or downstream, is called Position 1?
Any idea if it's SOP to throw both banks, same position, even if only one side needs help?
Any idea if the PCM will disregard the ABS VIN mismatch forever, or will it eventually shut me down?

Thanks for reading! imp

 

[Number4]

Sensor one should be pre cat. Or first down the pipe. Bank one is on the same side as cylinder one.

I'd think the issue was from something other than the O2's, but that's not a professional opinion.

 

[imp]

Sensor one should be pre cat. Or first down the pipe. Bank one is on the same side as cylinder one.

I'd think the issue was from something other than the O2's, but that's not a professional opinion.

I really appreciate your response. I'm still wondering where that "professional opinion" you mention is to be found. Moreover, what opinion may be relied on? The difficulties I've covered in 3 threads now are viewed by many, answered by few. I expected at least some opinionated response, but very little. Evidently, my ABS troubles show few have delved into these issues very deeply at least in Gen 3 or beyond.

Anyhow, even though the HO2S Heater resistances came in OK, I replaced all 4 sensors. The DTCs before would post after 2 miles or less, with a CEL. I've driven it 30 miles now just fine. If I can convince the "General", we'll take it to town tomorrow!

How intriguing this has become! Like, mystifying. Truck ran for 5 years with no DTCs, threw a "Forced Limited Power", and I was "off to the races"! Then, unrelated issues like "Forced Engine Idle". That one scared me. Then, suddenly, the O2 sensor thing.

Happily, replacing all 4 O2 sensors may have cleared up that glitch. Tomorrow may tell. imp

 

[Number4]

My '05 4.0 has recently started to randomly act up. You'll be driving it and the cluster will start freaking out.

Alt. is fine, battery is fine. Watching my Ultra-Gauge as it happens, they both show correct voltage.

Adv Trc warning light comes on and stays on. Reading up on it, it appears to require a computer flash at the dealer. But why everything else on the cluster goes nuts? Wife's car. I'll have to drive it to get a better idea. Weird behavior though.

 

[imp]

My '05 4.0 has recently started to randomly act up. You'll be driving it and the cluster will start freaking out.

Alt. is fine, battery is fine. Watching my Ultra-Gauge as it happens, they both show correct voltage.

Adv Trc warning light comes on and stays on. Reading up on it, it appears to require a computer flash at the dealer. But why everything else on the cluster goes nuts? Wife's car. I'll have to drive it to get a better idea. Weird behavior though.

I've read up on the Adv Trc system, and it's quite complicated. Has all the stuff the regular ABS has, plus a whole bunch of added wizardry. Try "Yaw Controls", sensors built into the steering wheel, "Brake Pedal Acceleration" sensor, "Brake Pedal Location" sensor. The step by step repair procedure is at least a hundred pages long. imp

 

[imp]

For anyone interested, JUST IN CASE they experience something similar: The 4 new Oxygen Sensors installed, same two DTCs were being thrown. "Bank 1 Position 2 HO2S Heater Resistance", "Bank 2 Position 2 HO2S Heater Resistance". Now faced with tearing into the harness looking for continuity loss, shorts, opens, bad wires, good wires, the ball of wax was not appealing. I gambled and yanked out the PCM, replaced with known good one, been over 100 miles now, no CEL!

The PCM was erroneously throwing Heater Resistance DTCs for both sides, at the same time. That was the tip-off. imp

 

[Bushdrift]

For anyone interested, JUST IN CASE they experience something similar: The 4 new Oxygen Sensors installed, same two DTCs were being thrown. "Bank 1 Position 2 HO2S Heater Resistance", "Bank 2 Position 2 HO2S Heater Resistance". Now faced with tearing into the harness looking for continuity loss, shorts, opens, bad wires, good wires, the ball of wax was not appealing. I gambled and yanked out the PCM, replaced with known good one, been over 100 miles now, no CEL!

The PCM was erroneously throwing Heater Resistance DTCs for both sides, at the same time. That was the tip-off. imp

Did this fix your b2900 vin mismatch?

 

[Bushdrift]

And ABS light?

 

[imp]

And ABS light?

No, it did not. The ABS light remains ON, and throws VIN mismatch. But car runs fine, 100 or more miles, then throws P0054 "Oxygen Sensor Heater Resistance Bank 1 Position 2" and P0060 "Oxygen Sensor Heater Resistance Bank 2 Position 2, CEL is then ON, car runs fine. The O2 sensor connectors at the sensors are so damned hard to get at, I'm undecided as to how I'll proceed. Obviously, the harness has to be checked for continuity, and possibly a short to ground, but that should blow the fuse. One fuse feeds all 4 sensors. Two of them have transmission speed sensors in SERIES with their heaters, which makes no sense to me at all.

The 4 O2 sensors are brand new. I've read on some wizard's site that PCM can throw p0054 and p0060 even though no resistance problem exists, for several other reasons: "Bad" cat converters, intake manifold air leakage, that I looked for with the propane idle change test, found nothing. IOW, he says "unmeasured" air entering the engine can cause those codes. Who knows? imp