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Discussion Starter #1
Alright, I've had my car "running for a few months now, still working out bugs, on it.
Its running rich, you can smell it in the exhaust, I'm throwing codes for all 4 O2 sensors
several codes at a time, bank 1 sensor 1 "reached rich limit" others say check circuit.
I didn't know if all 4 sensors would go out at once. The car has run like this for about 2,000 miles total.

Things I've done:
cleaned: MAF, all four O2 sensors, plenum
replaced: plugs, wires, coil packs, EGR, fuel filter
Seafoamed the upper end, ran about 3 tanks with Seafoam through it and one tank with injector cleaner.

I checked my vacuum lines going to the fuel pressure regulator and EGR, don't feel any vacuum on the EGR line. What operates the vacuum solenoid (what tells it to open for the EGR?) Could this be the cause?

it has 92,XXX miles on it, should I just replace the O2s?
 

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Oxygen sensors can't be cleaned, and trying to do so might damage them. If the sensors are original, you should replace them regardless just based on the mileage. However, you must realize that oxygen sensors are just the messengers. If something is wrong somewhere else, changing the oxygen sensors ain't gonna fix anything.

The EGR valve is not supposed to have vacuum to it at idle. The only way to measure would be to have a vacuum gauge attached to the line and watch it while driving.

The specific codes might help to better direct you.
 

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Discussion Starter #4
Codes are:
P0135
P0141
P0155
P0161
P1132
P1152
 

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Codes are:
P0135
P0141
P0155
P0161
P1132
P1152
All O2 heater circuit codes. I would look for burnt or melted. open or shorted sensor wires and connectors; maybe test them with a continuity tester and new O2's
 

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Discussion Starter #6
I have had all four O2s out and unplugged, they looked okay.
 

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Discussion Starter #8
Thanks, Chris I'll look into the wiring harness.
Would this still cause the car to run rich even when its not throwing a CEL? (resetting the PCM) Granted, I understand the problem still exists, and the car is compensating, should I look toward the front end of the harness or the PCM itself?
 

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All O2 heater circuit codes. I would look for burnt or melted. open or shorted sensor wires and connectors; maybe test them with a continuity tester and new O2's
Not to quote myself, but get a VOM, and track it down.....
 

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Discussion Starter #11
The only thing I siliconed has been a little dab on my valve cover gasket where the front cover bolts to the block, and the gasket on the EGR. (I don't go overboard on the silicone, I hate the stuff oozing all over everything) But it was throwing the codes before I did the EGR.
I cleaned the O2s with carb cleaner. and a toothbrush.

Would the temp gauge for the cpu be different than the thermostat and actual engine temp?
 

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I cleaned the O2s with carb cleaner. and a toothbrush.
By doing that, you have guaranteed their death. You need to get new ones.

Would the temp gauge for the cpu be different than the thermostat and actual engine temp?
I don't understand what you are asking here. The computer uses a separate sensor for the coolant than the interior gauge uses. The thermostat doesn't have a sensor. The rating of the thermostat does not mean the engine will always be at that temperature.
 

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Discussion Starter #13
I had the parts guy tell me he had luck cleaning them in that fashion on his truck. LOL. Well, it was their time anyway, I have ordered some new Motorcraft ones.
I guess what I was asking (probably a silly question) was about the temp gauge, does it operate from the board or thermostat? (My temp gauge always stays within the norm)
 

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what you need to do is get your car on a scanner and pull up freeze frame data and look at all the sensors that are listed. see if your computer temperature sensor is stuck at a certain temperature or if your o2s are stuck at a certain reading. o2 should fluctuate and should not go above .9 volts but shouldn't drop below .2 volts. if they are stuck and you have replaced the o2s, your wiring or computer might be bad have you tried an injector balance test?
 

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NeXT technology

Master, I would like to ask you something. I have been a Network Manager/Engineer my whole life and one of the tools I use is a cable tester that uses near end cross-talk to find opens and shorts. For example, I had someone call me the other day that their computer workstation out in the shop wasn't working. I went and tested the ethernet cable to runs out to the building and found a short in the 1-2 wires about 106 feet from where I had it plugged into the tester (it tells you exactly where to find the problem). I went out and looked at the cable about 100 feet over and found where one of the employees had backed a box truck into the side of the building and pinched (broke/shorted) the cable.

My question is this: do they make a tool that say you could unplug the ECM, hook up the wires from the O2 sensor and it was tell you EXACTLY if/where the short/open is in the cable (like in inches) just as my cable tester does for ethernet cables (in feet)? At first I thought maybe the cables need to be twisted pair for NeXT technology to work correctly, but my tester will also test coax cable and there are no twisted pairs there. If anyone else knows of such a tool for auto wiring, please speak up!
 

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I don't know of a tool that is designed for generic wiring. Those tools typically test phone, network, or coax cables, and what they all have in common is that the signals are low-voltage transmissions. The same can't be said of all automotive wiring, but unless there is some certain physical property (besides their twisted pair or shielded construction) that I don't know about, I imagine the same tool can be used. The way it works is that it measures the reflection time of a pulse sent down the wire. But in all honesty, unless one is intimately familiar with wiring of the car, knowing the distance may not be too helpful. Take the starter solenoid activation wire for example. If you know the short is 10 ft from the starter end of the wire, you also have to know that this wire runs from the starter to the engine bay harness to the dash harness to the trans harness back to the MLPS back to the trans harness then to the dash harness to the ignition switch and then back to the engine bay harness where it merges with the power wires at the power distribution box and then finally goes to the battery. The EVTM will tell you all these junctions but won't tell you the distances between. Of course it is better than not knowing anything at all, but you get the idea.

Something interested for the automotive world is this tool: http://www.etooldirect.com/power-probe-model-ect2000-wireless-short-finder.html
 

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I had the problem with the P0135, P0141,P0155, and P0161 and codes. All 4 heater circuits. It ended up that the heater circuit in the PCM was fried. I had tested the functionality of each o2 heater circuit(at the pcm connector) and found that they all were functioning and getting 12v.

Break out the dvom and test test test. Start at the HEGO fuse in the fusebox and make sure you have at least 12v to the fuse box. I have to remember exactly which of the 4 wires on each sensor I tested but a search will probibly find the information.

EDIT::

My first topic on it

http://forums.tccoa.com/showthread.php?t=123827&highlight=P0135+p0141


And this is a more in depth, detailed topic we had going. Follow that one when you start testing things. There's a LOT of good info there.

http://forums.tccoa.com/showthread.php?t=124881
 

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I don't know of a tool that is designed for generic wiring. Those tools typically test phone, network, or coax cables, and what they all have in common is that the signals are low-voltage transmissions. The same can't be said of all automotive wiring, but unless there is some certain physical property (besides their twisted pair or shielded construction) that I don't know about, I imagine the same tool can be used. The way it works is that it measures the reflection time of a pulse sent down the wire. But in all honesty, unless one is intimately familiar with wiring of the car, knowing the distance may not be too helpful. Take the starter solenoid activation wire for example. If you know the short is 10 ft from the starter end of the wire, you also have to know that this wire runs from the starter to the engine bay harness to the dash harness to the trans harness back to the MLPS back to the trans harness then to the dash harness to the ignition switch and then back to the engine bay harness where it merges with the power wires at the power distribution box and then finally goes to the battery. The EVTM will tell you all these junctions but won't tell you the distances between. Of course it is better than not knowing anything at all, but you get the idea.

Something interested for the automotive world is this tool: http://www.etooldirect.com/power-probe-model-ect2000-wireless-short-finder.html
Well, I think a tool marketed like that would be a HIT! :eek: How many people feel so lost when starting to try to find a short or open ANYWHERE in a wire harness? BTW, I am familiar with the way the tool works, but I'm not so sure I could use that particular unit with any accuracy on automotive wiring. But a unit DESIGNED particularly for automotive I think would sell like hot-cakes because it would be very useful to most people. Not everyone has the knowledge/experience in your head and/or the resources you have access to, that's why I'm talking about the general masses. Maybe sell it with a trial subscription to AllData, so that a person would have access to schematics and wiring diagrams. Huh? Huh? What do you think?
 

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Good luck with that. :)

The only thing that makes TDR(time domain reflectometry) work is a transmission line set of wires; coax or twisted pair. On PC boards, it only works with ground planes or matched pairs.

http://en.wikipedia.org/wiki/Time-domain_reflectometer

Otherwise, there's no clear reflection.

Also, you will see a reflection from each connector in the line. :)

If you can make that work, there's a bunch of companies that will hire you. :thumbsup:

It could marginally work with the shielded wires; afaicr the knock sensors, cam, and crank sensors might possibly be testable like that. (yeah, only the new motors come with knock sensors.) But then there's the connectors.
 
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