Hey all,
Picked up a Base 3.2 Cayenne a few months ago and I can finally say it's back on the road!
When I got it, the clutch and flywheel needed to be replaced as well as brakes and the exhaust need help. Started working through the issues and I've got most of them sorted except a check engine light, headlight mounting issue and a stereo quandry.

 

Your front 02 sensors are responsible for fuel trim and lean codes...

 

Popping noise sounds like a bad semiconductor in the amp.

 

The O2 sensors both seem to be reading the same. I figured since both are showing lean combustion at idle that they were both working okay. I have the torque app that allows me to monitor some parameters but not sure what the specs should be for a good one at idle. I'll take a look at them again and see if a can see ay issues with them. Still doesn't explain the high vacuum on the valve cover. Maybe I've got multiple issues still

Are the semiconductor(s) replaceable or do I need a new amp? Where would I look for a used one? EBay?
Thanks!

 

High vacuum could be the PCV system, or air oil separation.

 

Unlikely you can find the exact part you need to repair the amplifier (if that is the problem). You could also have corrosion in wiring somewhere, potentially from having 1 or more water drains plugged... typically when that happens you'll find it damp under the carpet on one or both sides. Any wire splices or connectors under the carpet are subject to being wet and corroding when there are problems with 1 or more plugged rain drains. I think there may also have been a few cases of the air conditioning condensation drain hose slipping off allowing the condensed water drops to collect in the front passenger footwell (right side).

Also, if you have a Bose audio system, the components they use aren't generally directly replaceable by some more typical amplifier... you'll need the same amp either new, repaired, or salvaged from another vehicle.

Looking at the spark plugs can help you determine whether there is a "real" lean running condition or not.

How many miles on the vehicle you have? It is possible that the O2 sensors are just "old" and it's time to replace them... it's possible they have been performing fine and aging at the same rate and having reached the end of their useful life, they continue to perform similarly.

Also, some 955 Cayenne V8s have 2 batteries... one under the seat, one in the cargo compartment... if the V6s have 2 batteries also it's POSSIBLE the previous owner replaced the "known" battery under the seat but did not change the battery in the cargo compartment. I'm not sure if V6 models have 2 batteries or not. If there is a second battery in your car and it is dead, you could have odd electrical prooblems.

 

 

Thanks for the replies...

The car has 143k miles on it. Ill check the carpets to see if they feel wet.
Is the PCV the one under the valve cover? Seems like a royal PITA to change. If that's what needs to be done that's fine, but how do I know that it's the problem? Any test(s) i can do prior? I looked at the oil separator and it looked fine, no tares in the diaphragm that I could see.

The stereo is a base unit I think as I don't see Bose written any place so I assume it's the basic system. I'll check the spair tire well and see if it's damp.