Car is out of warranty.

Throttle body was replaced, coils and spark plugs are being checked now, but what else could it be? Car has 50k miles. Drives fine, but has a tad of rough idle (rpm is still). No cel. No codes.

Fuel pump? Fuel filter? How to diagnose, and whats the likely culprint?

 

maybe dirty camshaft sensor ?

 

I changed the fuel pump on mine(2004) and it solved the rough idle.

 

Can you describe the rough idle a bit better?

• Do you hear it? Do you feel it?
• What makes it rough?
• Was it formerly smoother?

And the fuel system on your 2011 and the 2004 are nothing at all alike. Entirely different.

 

When in idle, and sitting in drivers seat, there are small vibrations. Rpms are steady. Engine shakes a bit.

Mechanics are saying Chain tensioner...

 

I'd say that's really doubtful at that mileage. I saw my chain tensioners recently - at 60,000 miles - and no wear was noticeable.

Are the mechanics reading variations off the cam positions sensors? Or are they simply guessing?

BTW - you never answer the really critical question: Was it formerly smoother?

 

They are guessing, they took off the valve cover and saw some play in it.

This is a vehicle im looking to buy, they offered it to me, but i asked them to fix the issue before i pay the money. There are no other cars around me with same mileage/options/color/price.

It doesnt seem like a natural vibration, it is noticible. Almost like misfire. When driving, its fine.

 

They changed the tensioner, car still vibrates at idle. They cleaned up some carbon build up around the intake, but are saying it might just need some hard driving to burn it off

 

Unlikely. Have they run a bottle of Techron through it? It's possible the injectors are a bit plugged up and Techron will help clear that up.

Whatever - if it doesn't meet your standards - then wait to find one that does.

 

Obd 2 gives following codes:
P1361 1372 1363 1372

Ignition control cylinder 3 and 6 short circuit to ground, as well as open circuit

 

I'd suggest getting a Porsche specific code reader on it. The P1### and up codes are MANUFACTURER specific. Most generic OBD-II code readers try to assign an explanation to the codes based on their use by a large manufacturer like Ford. That may not be the same as what Porsche uses the same code number to indicate. And the use of the codes may vary model to model and year to year.

You need something like the Durametric or iCarScan, or the Porsche PWIS system. Or they can continue to throw money at guesses - in this case my "guess" would be coils. Certainly not unknown on a Cayenne. Might as well get them to do all 8. If 2 are bad, the other ones are right behind them waiting to fail.

 

They sell quite a few porsche's, and their scanner is some fancy one. They have a 2011 ptt, and they took coils off of her, and swapped them to see if that fixed the issue. It didnt. So not coils.

They adjusted the timing, replaced the timing tensioner, put in new spark plugs, cleaned carbon off the intake. Now they are saying maybe its a bad ecu. Initially, they noticed that the car's drainage system was clugged up, which caused water to accumilate in the ecu area, and one of the connectors was bad, so they fixed it, but perhaps some damage was done to ecu.

I test drove the car today for about an hour, it drives great, except when its at idle, at idle it feels like its misfiring. Rpms are steady, but u get the feeling through the steering and the seat, and engine shakes a bit. Its not very bad, but it is noticable. At all other rpms, its working fine.

Im in a tricky situation, im in the military, and am in the middle of a pcs, so i planned my move around this vehicle, so i can drive it to my next duty station. So thats why im posting here, to see if i can get some more insight into this issue. The guys doing the work on the car are great, so is the dealer, but i figured id give the forums a shot.

 

The codes showing - if they are the Porsche specific code explanations are pointing at the ECU or the wiring to/from it. Replacing the ECU is $$$, and I don't believe a used one can be recoded to work with a different VIN#. If it was me, I'd be examining the wiring to the ECU very carefully. If water got around the connector - it can get sucked up into the wiring by capillary action and the wire can corrode internally - looking fine on the outside.

That's fairly common on Cayennes (especially 955/957's) where the footwells fill up with water if some of the drains get clogged. There are several major wire bundles that go through the area - and they have in-line splices, that you can't see if you don't take the bundling tape off the harness. They tend to go around the splices. Might be worth seeing if that's what happened on this one - but around the ECU.

 

so i just had to replace one of the gaskets for the thermostat housing, talk about a pain. After it was done I now get the same codes you listed. the engine runs fine if I take it easy, the check engine will go away. If I drive it aggressive then go back to easy it will idle a bit rough then the cel will come on. If I keep it in sport mode and drive it "spirited" no cel or rough idle. The duramtric says implausible signal or short circuit to ground for those codes and I haven't found anything else online. I basically have the same car the poster mentioned 2011 TT with 85000 miles. Ran a bottle of techron through it and have replaced 3 of the coil packs since I got it 13k miles ago.

 

If 3 coil packs went bad - the other 5 are waiting to fail. Do them ALL at once.