zer026T

Friend of mine scanned with the Durametric after a CEL came up about a week ago. CEL appeared while coasting through a parking lot at work after being parked all day. No performance issues whatsoever since the CEL appeared. I'm covered under CPO until January. Thoughts?

Quadcammer

covered by warranty....bring it in.

Spiffyjiff

a buck says it's MAF. unplug that little bastard and start car again. if running smooth(er) then it's the MAF. either way, yeah bring it in asap since it warranty.

Macster

First I agree with the others: under CPO? Take the car in.

What will likely happen is absent any untoward behavior from the engine the tech will read then clear the codes and advise you to drive the car. If the codes come back bring the car back.

That's a lot of misfires. Would have to be a common failure I would think. What's common to all cylinders? Well, as another poster mentioned there's the MAF.

Based on what I gather misfires from MAF are not that common. Usually a bad or going bad MAF makes itself known by other error codes related to fuel adjustment limits.

But the MAF needs to be considered. A nice thing too is if it is the MAF the misfire codes or possibly even other codes will appear and that's that.

How many miles on the car? Do you drive it in all kinds of weather? Did the weather change from when the car was parked to when you started the engine again?

I had two misfire incidents from cars one just sitting out overnight in a heavy fog (and another time sitting out overnight in heavy rain storm) or another time when the day that was nice and dry and warm turned into a cold damp night.

I'm thinking coils of course.

If plugs are due or close to being due to be changed (if not on miles then on time) you might have the plugs changed and at the same time the tech can inspect the coils and advise you. If they are in fact the cause of the misfires their condition should obviously reflect this.

myw

based on the service history of my car this had happened once.... all spark plugs needed replacing (work done at pfaff) was the major culprit.

zer026T

Cleared the codes, will wait to see if they come back. Will still put another 2k-3k miles on the car before winter (before the CPO expires).

27k miles.. Wet/dry driving in above freezing temperatures.

Coils were done last year (several cracked). Is it plausible the plugs would all throw misfire codes within the week since the CEL appeared?

That's where I'm leaning at this point..

Spoddle

I just ran into a similar issue with the same codes. Any chance you found the culprit?

zer026T

I cleared the codes and they haven't returned since.

Spoddle

Good to hear. Thanks for the update.

wc11

I've found that on the odd occasion, when I roll car out of the garage to wash or to do stuff in the garage and then start it to just put it away, I get the occasional misfire.

CAVU

Are you running stock (paper) or aftermarket (e.g. K&N) air filters?

zer026T

Presumably stock, it had its 30k KM service performed just before I purchased from a Porsche dealer, which (should have?) included replacing the air filter.

wc11

If the previous changed to a K&N, then the service dept will not change it as you would need to wash & re-oil it.
Too much oil though can bugger up the MAF

john997

I had the same issue. Tried new coils and plugs, crankshaft sensor, smoke test (no leaks), air mass sensor. All to no avail - CEL would periodically come on.

Finally took it to a different shop - and turns out it was a bad flywheel. Flywheel replaced and no problems since.

zer026T

No CELs to report of but scanned with my diagnostic cable and the misfiring has returned. Is that possible without throwing a CEL? I have an appointment Wednesday to have them check it out, along with a few other things.