Need some help..getting ready drive..i mean push off cliff

[working4it]

I am absolutely going nuts....I am getting ready to push my pig off the cliff. My 04 s has been pretty good but lately I have been bleeding money with it. Recently I had a PSM workshop message had a bad battery( replaced both for good measures) and a bad alternator. Replaced them. Then I had oil pressure switch go bad, then I started blowing a fuse from a faulty fuel pump. Replaced them. Then I had a cam sensor go bad replaced it. (not all at once but over 6 months)Now I am getting a PSM failure message with the following faults and the car will only turn over but will not start.

P2186 Throttle peddle sensorswitch voltage correlation

P2170 Throttlepeddle sensor d circuit below limit

P2174 Throttle peddle sensor switch e circuit below limit

P1514 Throttle adjust unit upper limit value exceeded

P2186 terminal use 30 for vehicle electrical control module-upper limit exceeded. Test conditions not complet

Do I put in a new throttle body? What's the P2186 code?

Edited March 16, 2013 by working4it

[Ahsai]

Part#15 under "Charge management and fuel supply"? Should be close to the gas pedal. On my 996, it's under the dash above the gas pedal. http://www.renntech.org/forums/tutorials/article/289-cayenne-v8-engine-parts-locations/

Edited March 16, 2013 by Ahsai

[working4it]

What does it look like?

[Ahsai]

I'm not 100% sure but it looks like it's integrated into the gas pedal itself (see the attached that shows electrical pins/connection).

gas-pedal.pdf

Edited March 16, 2013 by Ahsai

[working4it]

That's what I thought...I couldn't find any switch other than the unit itself. Now the question is if you replace it do you have to program it to the car

[Loren]

That's what I thought...I couldn't find any switch other than the unit itself. Now the question is if you replace it do you have to program it to the car

"For the learning and adaptation routine of the throttle (E-gas), switch the ignition on for 30 seconds without starting the engine. Do not actuate accelerator pedal. This completes the adaptation of the throttle adjusting unit and the programming sequence is complete."

[working4it]

Thanks Loren...have you seen the P2186 fault?

[Loren]

No I have not.

Have you reset the codes and seen if they reproduce?

[wvicary]

A lot of odd issues, it sounds more like a wiring issue. Have you had any issues with water migration or inspected the DME connectors and ground points?

[working4it]

Yes, when the alternator was put in we checked everything out and all were good. Nice and tight no corrosion.

[working4it]

Update... I have been able to get all of the codes go away and psm message but have one left P0112 temp sensor. The cayenne will turn over but will not start. I have replaced the MAFs(both), pedal sensor. i need some thoughts on what to do next...if I don't figure this out soon i am going to let it roll down the hill into the lake.. 'either that or i am going to go into the poor house.....

[Ahsai]

Any basic diagnostic on spark and fuel during cranking? A temp sensor itself should not prevent the engine from starting.

[working4it]

Update#2

Well I towed my Cayenne to my indie shop and they started by testing the fuel pumps since they just replaced them. They tested fine. Then they did a fuel pressure test and they said it was great (static and something else I can't remember. I thought they said it was at 55?). Then they inspected the coils( version ending 08), plugs and tested current and end spark. All tested fine. Then they did a cylinder pressure test and all tested within specs accept cylinder 5 which was slightly low but within tolerances. The car will turn over but not start. I have them putting in new plugs as it has been a couple of years. They are going to continue diagnosis but already up to $450. Any thoughts? Suggestions...btw the only code that it is throwing is the air temp sensor p0112.

[Ahsai]

So have they actually verified the injectors are indeed firing ?

They have already eliminated quite a bit. Have they checked the air intake for blockage (highly unlikely).

Edited April 2, 2013 by Ahsai

[working4it]

Great question, don't know specifically. I will ask them. I do know they did mention that the plugs were wet after the multiple test of starting.

[Ahsai]

I think the intake temp sensor is integrated in the MAF? Seems you have to trace the root of the P0112 complain since that's very well related to the no-start condition. Did they try unplugging both MAFs to start the car? The MAFs are genunie Porsche parts, right?

It's a real head scratcher!

[bigbuzuki]

Try this.

P0112.pdf

[working4it]

Update#3

Just got off the phone with my Indie shop. Still nothing on my Cayenne. They verified injectors, verified electric/spark, verified compression, verified fuel/fuel pressure. No codes other than air/temp sensor. They "think" its an electric "timing" issue. They asked me to leave it so they can look into it. The tech is pretty good and only works on Porsches. He had his buddy from Hendrick Porsche come over and they supposedly looked at for over an hour and they were able to get it to backfire which leads them to think a timing issue. They said it does not look mechanical but electrical. What could cause it to turn over but not start?

[bigbuzuki]

I'd get them to check the air temp sensor electrical circuit from the ECU to the air temp sensor.

[working4it]

Update #4

Indie shop called and the car is running now. They kept it another day just to make sure it would start. They said they traced the issue to a dead Cam Sensor Bank1 that was not throwing codes. Thats interesting since I changed that part out myself with a brand new one. Official porsche part too. The car is still throwing the air temp code. They said they swapped the MAF's cleared and the code came back. They checked out the plug/cord and it looked okay. Is there a way to reset the DME or something specific with my Durametric? I am picking it up this afternoon as i need to let the bleeding of money wound heal....

[Ahsai]

Wow, they did a good job diagnosting the problem. Hope everything goes well from here.

You can use the Durametric to reset the DME, which will reset the air temp code.

Edited April 10, 2013 by Ahsai

[bigbuzuki]

The fact that the camshaft sensor was faulty and was not registering any code, along with the persistant air temp fault may suggest an issue with the DME itself.

Let's hope the DME reset clears things up, although the service people should have done this through the PIWIS.