Low RPM hesitation while accelerating - 6MT car

[///M3Fresh]

For the past few months I have noticed a low RPM, higher gear, medium to high throttle input hesitation. Before I go any further, I understand the "stop lugging your engine" folks and I am not doing this on the norm but there are instances that present themselves and the car should perform the tasks just fine. This is my 3rd E9X M3 but first in a MT. My first two were DCT cars so I dont know if this might be normal behavior for the 6MT.

Under these conditions I can replicate the issue:

• Any gear, but most pronounced in 2-6th,
• RPM's between 1900 till about ~2700 or so,
• Throttle input @ ~ 35%+ (or what ever the equivalent is for pedal input of that percentage),
• Cold or warm, temps are irrelevant.

The feeling is almost like a misfire. Or a light bucking/hiccup. If you are a passenger you would not feel it unless you are told or I stayed on the throttle in short bursts but not actually gain enough speed to move out of the above RPM range. The car DOES NOT throw any codes. Thus being very difficult to diagnose.

• Car is a 2008 MY,
• 6MT,
• 94K miles,
• Stock DME,
• Stock Exhaust apart from muffler mod from previous owner,
• plugs replaced 2 months ago,
• coils replaced about ~36K miles ago,
• Fuel breather valve replaced at time of spark plugs,
• LPFS (driver strut tower area) replaced when plugs were done.

Only things I can possibly think it could be is maybe coils and or throttle actuators. I have had both go bad on previous cars and both threw their respective codes. I have done some reading into this and consensus appears to be that its normal? And you should keep the revs over 3K. I don't believe it to be normal. Anyone else run into a similar issue like this?

[tdott]

Any idea on dme version? I had a similar issue with no codes or check engine light until I updated the dme to 241E then it started to throw a misfire code which turned out to be a bad coil. But maybe yours is something similar or atleast a code will appear. The newer software must be better at detecting small faults or the dme update caused something to change. (even thought I had previously reset adaptations and other stuff over a 1 year period)

It was odd because the car pulled strong beyond the low rpm hesitation/studder.

[///M3Fresh]

Originally Posted by tdott

Any idea on dme version? I had a similar issue with no codes or check engine light until I updated the dme to 241E then it started to throw a misfire code which turned out to be a bad coil. But maybe yours is something similar or atleast a code will appear. The newer software must be better at detecting small faults or the dme update caused something to change. (even thought I had previously reset adaptations and other stuff over a 1 year period)

It was odd because the car pulled strong beyond the low rpm hesitation/studder.

Going from memory, I thought there was a recall for these cars for DME SW updates but I could be wrong. Just reviewed Carfax and looked thru to make sure nothing was missed. And appears to be up to date, whatever what means from carfax.. haha

I was able to scan it with a generic scanner thats more porsche specific and got the following values:

CID1: 7841364
CID2: 7841654
CVN1: 277DE1AB
CVN2: 491B4AB2

I am assuming the 2nd number is the SW version. So I have a feeling it might still be on 240E or something older based on a google search. Anyway to convert the above number to the DME versions numbers we are familiar with?

[tdott]

Originally Posted by ///M3Fresh

Anyway to convert the above number to the DME versions numbers we are familiar with?

Sorry I am not familiar with those.

I use MSS6X Flasher to read the version with a dcan cable.