06 S60 R MAFS / Surge

SSR · Post by **SSR** » 26 Nov 2014, 10:53

New guy here first post.
So we picked up a low mileage 06 last summer and it has been a tremendous car but. . .
When the weather went cold it developed a surge at idle. If this was a Carbureted engine I would say a lean surge at idle. No Codes were stored and the issue seemed at first to be randomly intermittent.
The first code/CEL stored occurred with the engine at operating temperature and intake air below 32°F. The incident described was a small 'backfire' and the CEL appeared with the engine idle now looping from 700-RPM to perhaps a few hundred to zero and a restart.
Pulling the code revealed a P0101 which I expected due to the K&N Filter. Cleaning the MAFS the complete intake, air box, the MAFS-housing, and the K&N appeared to solve the issue, for a day. The next CEL occurred at an ambient of 45° and operating temp, subsequent investigation showed 2 stacked P0101 codes and nothing else, re cleaning the MAFS and installing the K&N dry appeared to solve the problem again; which gets me to this morning back down to 31°F and a cold start the car went though high idle dropping to normal Idle in park and when put in to reverse began to surge again; an amount that can not be seen on the tach, but can be seen on the boost gauge.

Mods to the Car:
K&N Filter
Snabb (or?) Turbo intake Pipe
ARD Tune
IPD Cat Back

Thanks for any insight!
Chris, who is new to this chassis and been building Cars, Trucks, Etc, for 35 years

Post by **matthew1** » 26 Nov 2014, 16:06

Do you have the old air filter? If so, put that back in to do an "A/B" test.

SSR · Post by **SSR** » 26 Nov 2014, 16:33

matthew1 wrote:Do you have the old air filter? If so, put that back in to do an "A/B" test.

Unfortunately I do not have the original filter the K&N was on the car.
I am seriously looking at buying a OE type filter ($25 @ IPD) to make this kind of a test.
However, I figured I may as well ask if this condition is semi common to this otherwise terrific ride.

Post by **matthew1** » 26 Nov 2014, 16:37

Not common. Something's wrong.

Did something happen besides cold weather? New part?

importCar · Post by **importCar** » 29 Nov 2014, 10:10

Did you check possible leak from maf to intake? Many people mentioned this when dealing with this code.

SSR · Post by **SSR** » 01 Dec 2014, 18:34

matthew1 wrote:Not common. Something's wrong.

Did something happen besides cold weather? New part?

Nothing other then cold weather changed that I know of.

SSR · Post by **SSR** » 01 Dec 2014, 18:36

importCar wrote:Did you check possible leak from maf to intake? Many people mentioned this when dealing with this code.

I disconnected the MAF cleaned and was careful to reinstall everything correctly...

SSR · Post by **SSR** » 04 Dec 2014, 09:51

Just spoke to a local Service tech who said if the symptom (Surge) disappears with the MAFS disconnected the problem is the MAFS. Worth a try...

SSR · Post by **SSR** » 11 Dec 2014, 15:11

Minor update.
I checked everything I could see, disconnected the MAFS and the problem went away so I replaced the MAFS and apparently the problem was solved and it was... until it came back yesterday! At which point I made an appointment with a local independent shop that didn't immediately say sight unseen it was the short list of mods.
I hope that we can find it and when that happens I'll be sure to post the results.

SSR · Post by **SSR** » 17 Dec 2014, 11:55

Here is the update.
Pulling codes with a good code reader pulled 6 codes with the most likely cause for all being a misfire on #2 replaced that coil.
The car seemed to run fine. This issue has been intermittent so when it stumbled at the first stop light off the highway this AM I got a call and I hope that was a fluke... didn't set the CEL.
I wish I could see the maps to know exactly what the tune changed it is possible that the car's change in geography is taking it off the Map.
I also need to invest in whatever code reader/diagnostic tools so that I can work on this car.
Intermittent's are a pain, but having to rely on a shop that is 30 miles away no matter how good these guys are is just not going to cut it; because it is never going to glitch while at the shop