7 replies to this topic

[the_bruiser]

Model: Cooper MPi
Year: 1999

Description of problem

My Mini keeps over revving! I've changed the lambda sensor but it only worked for a few days, I've been told it could be something to do with the ECU is this likely?

When driving and I put the clutch in to change gear it over-revs, sometimes it disappears when I blip the throttle but I have to blip it higher than 3000rpm, it revs at anything from just below 1000 to 1500, but it was plenty worse before I changed the sensor. If it does need to visit the ECU man for a diagnostic check how much you reckon I'm looking at paying to get it sorted? Or has anyone had this problem before and can you advise me?

Any non-standard parts that might be involved with the problem?

None

Edited by Purple Tom, 14 September 2008 - 05:05 PM.
Edited and moved to injection section

[taffy1967]

This any help?: -

http://matsone.csuea...ges/x8479bu.pdf

[shedonwheels]

Hi I'm having very similar probs with revs on my 99 mpi cooper too. I took it for a test and fault codes came back for the coolant air temp sensor and ambient air temperature. The mechanic cleared these error codes on the ecu and this seemed to sort things. I was sent away to drive about and see if things remained fixed. They did....for two days.
If I'm honest I didnt think just clearing the codes would work but you always hope don't you. There must have been some kind of fault with the wiring or some such to cause a fault code in the first place.
Will be taking the min back for a second look where I'll hopefully get the coolant temp sensor replaced. Not sure how much this will cost? I managed to get the plug in test done for free but it should have cost me £25. I have heard certain sensors cost £60. How much was your lambda sensor?

Thanks for that diagram and pic taffy, wil be printing that off and taking with me! My mechanic man couldnt find where the sensor was when he looked.

Edited by shedonwheels, 14 September 2008 - 10:07 PM.

[Cian 'the pain' MPI]

I had the same problem when i got mine a few years ago, found that the stepper motor had broke off!, changed that and she has been running great since

Hope this is a help

[mini_lover]

Mine was doing this as well - turned out to be the accelerator cable. My Uncle (a mechanic) just adjusted the path it was taking under the bonnet slightly and slackened it a bit and its been fine since.

[taffy1967]

Thanks for that diagram and pic taffy, wil be printing that off and taking with me! My mechanic man couldnt find where the sensor was when he looked.

No problem, I believe the parts cost around 40 quid?

[the_bruiser]

Hi I'm having very similar probs with revs on my 99 mpi cooper too. I took it for a test and fault codes came back for the coolant air temp sensor and ambient air temperature. The mechanic cleared these error codes on the ecu and this seemed to sort things. I was sent away to drive about and see if things remained fixed. They did....for two days.
If I'm honest I didnt think just clearing the codes would work but you always hope don't you. There must have been some kind of fault with the wiring or some such to cause a fault code in the first place.
Will be taking the min back for a second look where I'll hopefully get the coolant temp sensor replaced. Not sure how much this will cost? I managed to get the plug in test done for free but it should have cost me £25. I have heard certain sensors cost £60. How much was your lambda sensor?

Thanks for that diagram and pic taffy, wil be printing that off and taking with me! My mechanic man couldnt find where the sensor was when he looked.

yeah they are about 40quid, thanks for the advice dudes and dudettes, i'll look into this and see what happens will keep yall informed

[the_bruiser]

This any help?: -

http://matsone.csuea...ges/x8479bu.pdf

taffy that looks pretty helpfull i might get it hooked up anyway first and see what they say, its only 25quid atleast then i'll go down the sensor road probably.