P0456 code - Very small evaporative system leak

[rlim]

The CEL has been with me for about 3 years and it only happens in the fall/winter period.  It mysteriously disappears during the summer period.  It is a 2008 Cayenne V6 (base).  I’ve had the gas cap and purge valve replaced and the CEL (P0456) still appear during the cooler period.  I used to have to reset the CEL every week or so but the code is appearing more frequently lately … within 1 -2 days. 

 

I've decided to drop by another local mechanic today whom I’ve dealt with once to replace my stabilizer bar links on my 996 in the fall of 2015.  I explained the CEL code and the parts (cap and purge valve) I’ve replaced and asked if he has smoke machine he can use to diagnose the leak.  He stated it is the “leak detection pump” which he said is a common problem for the Cayenne.  He currently has a 09 Cayenne S on the hoist that he had just replaced the LDP with a similar problem.  He quoted me about $750 (CDN) for parts and labour as he stated the LDP is about $450 and 2.5 labour. 

 

$750 is quite a bit of money to be paying to replace the LDP which I’m unsure is the source of the leak.  Is the LDP a common evap emission problem for the Cayenne as he stated?   Is it a fairly simple DIY project … I’ve been told it is located in the rear passenger wheel well.

[amfiuvo]

rlim

 

Just had the same code!

 

Did you find the problem? Did you fix it?