To preface: Over the last couple months I've had the transmission rebuilt, installed LNE IMS bearing upgrade, RMS, AOS, new clutch, etc. So in total, I've spent about $6,000.

Yesterday I drove 500 miles from Nashville to Charlottesville, VA. I stopped for gas outside of Knoxville and my CEL came on once I started it, along with a really rough/erratic idle. Took it to Autozone and had them read the code - they said it was a Throttle Position Sensor. There's a Porsche dealer a mile from my hotel, so I dropped it there, they wanted $70 to diagnose it.

They jumped to the conclusion that it's the camshaft actuator and quoted me $3,300. Obviously, if that was the problem, I'd take it to my local independent guy, who is well known and respected in my area. So, I called him... he said go get the car immediately and that he doesn't buy their explanation.

Does anyone else have any thoughts our ideas?

I'm just kind of ready to be done with this. I've spent $6K in the last 2 months on it. The law of averages says that stuff shouldn't keep going wrong, so I should keep it. What are the odds that stuff continues to happen? I don't know, but it's getting irritating. So basically I've dumped around $30K into a car that I could MAYBE sell for about $18-20K privately (given the rebuilt transmission, IMS bearing upgrade, RMS updated, new clutch, new AOS, etc).

I don't know what to do. I love the car... LOVE IT! 65 out today and I had to drive to DC, ran great (except at idle) and I had a blast, but I hate the fact that it's always in the shop and at my age I'm missing out on huge opportunities for compound interest with investing. Cars are my passion though and I technically have money to do both. I don't know, I don't know...

Thanks in advance for responses. May take me a while to respond as I'm on the road working and have a fairly busy schedule.

 

Gosh my guess is the throttle position sensor

Quick check is take a look at the cable going to the throttle body for being on correctly and not half cocked. Loose cable holders and such and spring doing the right thing. Would help to look at the sensor for being connected right and the wiring good for it too.

 

What was the code number?

 

my 2 cents: trust the code reader, buy/install the TPS and see if rough idle is fixed. Pretty sure this option will be much less than the dealer quote of $3300. Best of luck.

 

Trust the codes! Otherwise it's a guessing game.

 

Since I'm just about the least mechanically inclined person in the world, is there anywhere I can find a diagram of this area of the car? Or do I need to

 

I'll order the TPS, install it/have it installed and report back.

Car ran great most of the morning, idle was fine, etc. Stopped for gas and had a hard time starting it back up, CEL back on. Just need to get her back home then I can actually get work done on it.

 

Unlikely if the *only* error code pointed to the TPS that the camshaft actuator was at fault.

(When the VarioCam solenoid (and actuator) failed on my 02 Boxster the first sign of a problem -- rough running engine -- was at some point accompanied by a CEL and the error code read from the car's DME clearly pointed to the VarioCam solenoid/actuator.)

If the fuel tank level was rather low when you filled up the gas tank the rough running engine could have been due to 'bad gas' and the TPS error induced by the engine's rough running interfering in some way the TPS and the DME's attempt to control idle speed.

My opinion is that you should not have the VarioCam solenoid/actuator replaced on just that dealer's WAG, err diagnosis. There are procedures that can be done with the proper Porsche diagnostic computer to confirm or eliminate the solenoid/actuator from being bad.

Sincerely,

Macster.