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Transmission Hesitation at Initial Acceleration

511 Views 10 Replies 3 Participants Last post by  x3brian
After fixing my last issue on my 2009 x3 with approximately 264k miles, about 200 miles after fix started getting a hesitation at accelerating from a stopped position. Tends to be better in sport or manual mode but frankly is still there. When it happens, you hit accelerator, it initially goes slightly, long pause and then it will go. Sometimes between initial go and pause, a quick 4x4 light pops up for no reason other than it though wheels slipped. Just to be clear, I do believe the problem has been around for a bit but was masked with previous issue of a failed DISA. Now that all other issues have been resolved, time to tackle this one.

At the moment, all control units are happy and reporting no issues except for the following faults (these are faults AFTER issue actively happens):

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The RLS and KOMBI are related and are caused by a Safelight windshield I put on the car about 7 years ago to pass MD state inspection. I haven't spent a who lot of energy trying to get the RLS to initialize but I am sure I could with some coding and work.

That leaves the no comm's with TCU. I can easily see and clear faults and run troubleshooting on the EGS. Matter in fact, I reset adaptations and it is currently shifting fine. What's struggling to communicate is the EGS 0x32 module. Next step is to go through the troubleshooting process and check fuses but I am 99% sure that those will check out fine.

My suspicion right now is that I have an alternator that is starting to flake out. It was caked in oil from the OFHG failure and wouldn't be surprised if maybe that is causing the EGS module to see faulty voltages. Starter and battery were replaced about 5k miles ago...no issues starting and no issues with low voltage. Let me know if the group has any other working theories. Not a lot of other examples of this particular fault popping up so figured I better document it for the broader group.
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As I mentioned in the other thread, I’d be watching WSS live data. @abscate traced his power dip and lazy shifting to a bad axle tone ring. My quick power dip could have been in part due to flaking paint on the starboard rear axle (the SAS DTC definitely was).

Alternator output could definitely play a part, especially if original. Usually it’s the VR that faults, but you have high mileage if original alternator. Drive around with a scan tool monitoring voltage, preferably graphically, and watch for any outliers at the time of power dip.

Also monitor your throttle position with a scan tool to make sure that the pedal is actually communicating to the DME.


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Good idea on graphically watching voltage. Yes it’s original. I’ll try that tomorrow


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As I mentioned in the other thread, I’d be watching WSS live data. @abscate traced his power dip and lazy shifting to a bad axle tone ring. My quick power dip could have been in part due to flaking paint on the starboard rear axle (the SAS DTC definitely was).

Alternator output could definitely play a part, especially if original. Usually it’s the VR that faults, but you have high mileage if original alternator. Drive around with a scan tool monitoring voltage, preferably graphically, and watch for any outliers at the time of power dip.

Also monitor your throttle position with a scan tool to make sure that the pedal is actually communicating to the DME.


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And because of the 4x4 light, humor me and watch WSS. ;)


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Good idea on graphically watching voltage. Yes it’s original. I’ll try that tomorrow


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Good news, bad news….

Original alternator definitely was causing issues. I replaced it and installed a new battery. Interesting enough, the 2 year old h8 agm battery failed a test at the local auto parts store, so warranty replacement was obtained. Sure it was direct result of odd voltages coming off the VR

Other good news is I was able to get the transmission controller to come back to life with new battery and alternator after I pulled fuse 29 and reset it. At that point I reset all adaptations in the transmission.

Took the car on a long drive following the gs19.11 process…https://s3.amazonaws.com/fcp-creati...t_e90_transmission_adaptations/Software+T.png

Overall driving better but it really does feel like the solenoids in the transmission are not down or up shifting when they should (IE bog down on hills or shift to second or third at a stop light too fast cause a hesitations).

My gut right now is the transmission might be ready for a refresh kit at a transmission shop but open to other ideas.

I’ll Jack it up tomorrow and check driveline for anything funky just in case.


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Trans had new fluid, filter, and pan gasket?
About 8k miles ago I had the fluid and filter changed at the dealer when it was in for the recall and to code a new sas as a matter of convenience.

I’m aligned though, just placed an order about an hour ago for 7qts dex vi and a filter./gasket kit My thinking is it gives me a chance to see what’s in the pan.


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Trans had new fluid, filter, and pan gasket?
Don’t forget a bottle of Lubegard.


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Step ahead of you, picked up a quart yesterday at AutoZone when I grabbed the replacement battery before I ordered the kit from FCP.


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Don’t forget a bottle of Lubegard.


Buy socks on Amazon, not car parts.
Quick update, both my son and myself have been driving all week and feels like transmission relearn procedures brought it back 98%. Still seeing occasional clunk from 2-1 and a hesitation from 5-4 on acceleration.

I have him trained on how it should look when he is by himself and is pretty happy. FCP has fluid coming tomorrow, will swap on Saturday with lubegard.


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I’m going to finalize this thread for future google search

Random transmission shift issues on the N52 with gm 6l45 transmission, no codes.

Check battery and alternator. Once fixed, reset all adaptations INPA for transmission then follow link above from FCP on transmission relearn procedure.

Further safeguard, not solve, change fluid, filter and add lubegard.

I’ve got a happy 16 year old now. I might add also a 16 yo that knows how to change trans fluid, chase a vacuum leak, fix a coolant leak, change engine oil, bleed brakes and understand how a car shouldn’t drive.

I call this success.


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