First Time Cayenne Owner Needs Help

[daustinlucas]

Hello all. Thanks for having me. I recently purchased an 08 CS, and after lots of searching, I feel like it's time to ask for help with my current issue.

Symptoms are:

CEL with codes:

- 0455: Evaporative emission system leak detected (large leak).

- 2404: Evap. system leak detection pump sense circuit range / performance.

I had to email Durametric for these, as the SDI4 interpretation from their software seems to be a bit "off."

After clearing the CEL, I tightened the gas cap and did several warm starts throughout the day. CEL didn't come back until a few minutes after a cold start the next morning.

Cold start is slow. 6-7 more cranks than the immediate warm start.

Every once in a while I can smell fuel on a hot start, I can't seem to replicate this consistently.

I've enjoyed working on the truck, so far, and I'd like to continue to do such as long as I can. I just don't know what to attempt next. Should I have a local shop do a smoke test? Are there inexpensive maintenance items I should try first? Is this enough description that one of you is going to nail the problem without guessing?! Thanks in advance.

[binger]

If you don’t understand how the evap system works from A to Z the car should be looked at by a professional. To properly diagnose you will need a smoke machine and a DVOM or better yet OEM scanner. This is a complex system that is daunting to even the best Techs out there. Save yourself the time and money in the long run.

[daustinlucas]

Thanks, Bing. I took your advice. Most recent report from the shop is no vacuum in the rear of the car and oil on a check valve behind the motor. They haven't done the smoke test, yet.

[daustinlucas]

So, after $250 in diag, the shop has decided that the Leak Detection Pump has failed and will need to be replaced. They'll do this, and a follow-up smoke test, for another $500. Anyone have any thoughts? I'm about to start looking for a Leak Detection Pump DIY, but I haven't made a decision, yet.

[binger]

The part runs about $240 on the hight side. If they have not smoked the whole system to prove all is well you might spend more $$$ in the end. I will remind you this is one of the most difficult systems to diagnose with out the proper tools.

[daustinlucas]

That's good advice, Bing. It's very important to me that I do all the work I can. That's how I learned my 911 inside out, and I appreciate the car much more for it today. Still, it sounds like I should let this one go. The price is fair and, not having the service history, there's plenty of basic maintenance to keep me busy in the near future. Thanks again for your help.

[daustinlucas]

Well, I've taken it in twice. The first time they replaced the leak detection pump. The 2404 came back the same day. The second time they said they found a loose vacuum line. 2404 came back the next day. I'm starting to think I paid them to replace a functional leak detection pump, and they actually have no idea how to diagnose the problem. Does anyone know what else could send this code?

[daustinlucas]

Shop says, "We put in an extra check valve around the secondary vacuum pump behind the engine, but if that doesn't work, we'll have to pull the engine to replace the vacuum pump." My gut tells me to never let them work on the car again, but I'd really like some input.

[binger]

Like I said this is one of the most difficult systems to diagnose without the proper skills and tools. Frist they did not give you a proper diagnoses. Second you paid for a leak detection pump that did not need to be replaced. I would hammer them to give you some money back. I would not let them work on your vehicle at all. I dont know if you have bureau of auto repair in Texas. If you do I would report them if they do not play nice.