Macan Mystery?

[Lancerlot]

Travelling up the M5 in the Macan SD this week, the CEL suddenly came on and the glow plug light started flashing away. A few miles later the car went into limp mode. []

Luckily enough, being only a few miles from Bristol PC, I called in and they cleared the codes for me, reset the ECU and I was able to complete my journey without further ado.

Back home yesterday, I spoke to Exeter PC, who kindly offered to check the car over ahead of the Macan expedition next weekend since I didn't relish being recovered from the wilds of North Wales to North Devon on the back of a trailer! [&:]

Taking a look and plugging in the box of tricks, they could find nothing much wrong. However the suggestion is, it may have been an error caused by regeneration of the particulate filter. The vehicle does lots of short journeys and the exhaust system more likely than not gets a little choked up.

The tendency then is for the system to overheat slightly on longer journeys as it tries to burn off the excess soot and this produces an error code. Sounds like a plausible explanation to me.

I am told, if there's a repetition of the problem, to pull over, switch off and withdraw the ignition key, wait a few minutes then restart and hopefully the problem will be resolved. We shall see!
So far I have travelled a further 500 miles with no reoccurrence - so fingers crossed! ????

Regards,

Clive

 

[vitesse]

Strange that-one would have it that DPF regeneration was an automatic process with no impingement on vehicle performance-I have no experience with Porsche diesels but my 2004 BMW E61 530D SE is fitted with a DPF ,does a mix of short & long runs generally upto our daughter's home near Morpeth & on occasions after 80mph runs on the M6,the exhaust note changes to a more "drone " type sound clearly audible inside the car- then just reverts to the usual sound which is not normally that audible.
I was told this would be the regeneration mode-however the DPF warning light has never illuminated & never caused the car to enter "limp home " mode.

You are quite correct in that the process involves the ECU allowing the engine to run hotter for the process -the hotter exhaust gases burning out the carbon deposited/caught by the filter-process being controlled by the Lambda sensors the filter has fitted .

 

[Lancerlot]

The AA have produced an interesting and informative article on DPF's and regeneration here.
Regards,

Clive

 

[g7 tar]

Hi Clive
car went in on Tuesday for its second transfer box - plus the dme update - plus a forced regeneration (was that necessary). Done 112 miles and driving home from exeter tonight glow plug light flashes with engine management symble appears and car goes into limp mode !?! Needless to say OPC is first call at 8.30 Monday morning !!

 

[Lancerlot]

Oh dear Sue, you certainly don't seem to be having much luck with that car atm. Your symptoms sound exactly the same as mine.
I've started to wonder if that ECU recall/update has anything to do with the problem.

Did it reset once you switched off and removed the ignition key?

Regards,

Clive

 

[delboystoy]

Yep, me too now. Driving back round the M25 on Saturday and on came all the lights. Took the car in to the nearest OPC and no codes stored !! Had a call to say that it could be the DPF but this car only had a brand new engine fitted 1000 miles ago under warranty but that a different story.
Beginning to wonder if I made a good choice and now thinking I should have maybe kept my 997 but this car is just so comfortable and practical to drive while still bringing a bit of a smile when you put your foot down.
Well lets see what happens this week before making any rash decisions