528i auto gear problem

[Guetzer]

My buddy has a e39 528i and the car stays in one gear for wayy too long, it wont change down in a high gear when your just cruising slowly and revs really high before it changes up, even when driving slowly. Anyone have any ideas?

 

[jeff_denning]

Could be a few issues, ECU playing up maybe? Does the same thing happen both in normal and tip-tronic modes?

I'd start with a full diagnostic

 

[Guetzer]

Could be a few issues, ECU playing up maybe? Does the same thing happen both in normal and tip-tronic modes?

I'd start with a full diagnostic

hmm does the ECU also control the gear changes? its a 1997 so i dont think it has tip-tronic lol. he says the only way to get it to change gear is to put it in S then back in D then it goes in the right gear.... they have also replaced the gearbox fluid and the filter...

 

[P1000]

It is hard to say from guessing, but I would guess that the full throttle switch is either stuck, or the TCU is reading it as such. It is behind the throttle pedal. Either that or the throttle position is not correctly read by the TCU - also either a hardware fault or a wiring. Both of these should be very easy to diagnose with a diagnostic machine/interface and a capable operator.

 

[Guetzer]

It is hard to say from guessing, but I would guess that the full throttle switch is either stuck, or the TCU is reading it as such. It is behind the throttle pedal. Either that or the throttle position is not correctly read by the TCU - also either a hardware fault or a wiring. Both of these should be very easy to diagnose with a diagnostic machine/interface and a capable operator.

kewl thanks, ill tell him to check that and ill try and do a scan for fault codes, u maybe know if the 1997 model has an OBDII port inside the car?

 

[P1000]

It is hard to say from guessing, but I would guess that the full throttle switch is either stuck, or the TCU is reading it as such. It is behind the throttle pedal. Either that or the throttle position is not correctly read by the TCU - also either a hardware fault or a wiring. Both of these should be very easy to diagnose with a diagnostic machine/interface and a capable operator.

kewl thanks, ill tell him to check that and ill try and do a scan for fault codes, u maybe know if the 1997 model has an OBDII port inside the car?

It does not, you need the 20 pin round connector. (its in the engine bay)

 

[Guetzer]

It is hard to say from guessing, but I would guess that the full throttle switch is either stuck, or the TCU is reading it as such. It is behind the throttle pedal. Either that or the throttle position is not correctly read by the TCU - also either a hardware fault or a wiring. Both of these should be very easy to diagnose with a diagnostic machine/interface and a capable operator.

kewl thanks, ill tell him to check that and ill try and do a scan for fault codes, u maybe know if the 1997 model has an OBDII port inside the car?

It does not, you need the 20 pin round connector. (its in the engine bay)

ah damn... thnx