Acceleration stumble at highway speed Help!

[slater]

Pretty sure what you are describing is the infamous 2800 RPM hesitation on our cars. I've read that this can be fixed with a DME update.

i think it can be, and my ZHP suffers from the same thing. when the drivetrain goes in the Touring, i'll be flashing the Touring ECU with the latest revision (or the exact revision created to fix this issue).

[anandoc]

i think it can be, and my ZHP suffers from the same thing. when the drivetrain goes in the Touring, i'll be flashing the Touring ECU with the latest revision (or the exact revision created to fix this issue).

Guess who would be making a second trip to Picton?

[slater]

Guess who would be making a second trip to Picton?

LOL!

[ELCID86]

Have you tried unplugging the DISA wire plug and see if it performs better?

[daytona90t]

Have you tried unplugging the DISA wire plug and see if it performs better?

No I haven't. I thought about trying that though. I did rebuild the DISA about 2 years ago with the GAS kit, but I have heard that the vacuum diaphragm can fail as well.

[ELCID86]

Humor me and try it. I had a really bad stutter on acceleration and unplugging the DISA made it go away.

[daytona90t]

After verifying no change with DISA unplugged I checked my DME software version. I have SW-V5.1 version 7561382 with a build date of 05.08.2003. Since this is far from what should be the latest DME software version 7561520, I called my local dealership and spoke with the service manager. I am brining the car in in a few weeks for a DME and trans software update. They quoted me $145.00 to check and update the software. They said it should only take about an hour but set me up with a loaner just in case they don't get to it right away or in case the updates take longer. With service like that I cant complain about the quoted price. Part of me wants to hang around the dealership to make sure it goes smoothly, the rest of me wants to put some miles on the loaner. I will keep everyone up to date as to the outcome.

[ZHPizza]

After verifying no change with DISA unplugged I checked my DME software version. I have SW-V5.1 version 7561382 with a build date of 05.08.2003. Since this is far from what should be the latest DME software version 7561520, I called my local dealership and spoke with the service manager. I am brining the car in in a few weeks for a DME and trans software update. They quoted me $145.00 to check and update the software. They said it should take only take about an hour but set me up with a loaner just in case they don't get to it right away or in case the updates take longer. With service like that I cant complain about the quoted price. Part of me wants to hang around the dealership to make sure it goes smoothly, the rest of me wants to put some miles on the loaner. I will keep everyone up to date as to the outcome.

That sounds very reasonable. I bet they have cookies in the waiting area too.

[BMWCurves]

I always drive the loaner. Makes me appreciate my ZHP every time I step out of current BMWs and back into my ZHP.

EDIT: ZHPizza's right. Grab a cookie and coffee, then hoon the loaner.

[ELCID86]

Sorry that didn't help. About 1 hour of labor sounds about right. I hope that sorts it.