BMW - Automatic gearbox over-rev?!
Discussion
Right, they've checked it out and they say that no faults were logged in the system. I asked if max. revs were logged and the lady on the phone said that "The technician went through his test procedure and found nothing wrong" so I'm not too sure if thats a yes or a no.
I haven't picked it up yet, so before I pick it up - any questions that anybody recommends to ask?
Sunny.
I haven't picked it up yet, so before I pick it up - any questions that anybody recommends to ask?
Sunny.
I spoke with the technician - very nice chap - and he said that he couldn't find any over-rev logged, or indeed any other error. He said that the Engine/etc. is fine and that there are no error codes. He said that should it ever occur again, to bring it back, and then there may be some error codes which he cannot decode, but BMW in Germany can.
Which makes me think that it could have been the revometer that went flying past where it should have been.
Which makes me think that it could have been the revometer that went flying past where it should have been.
Spoof said:
My mate did a 5th to 2nd with his S3, it wasn't cheap to fix. He originally thought he was going to get away with a warranty claim until Audi saw the peak RPM log.
BMW should be able to see what RPM was logged, they may use it to deny a warranty claim later down the line.
Was this in an Automatic or a Manual?BMW should be able to see what RPM was logged, they may use it to deny a warranty claim later down the line.
Matt UK said:
Disco You said:
sunnydude959 said:
Okay, thanks guys! - Does the over-rev get recorded in the ECU? I'm thinking of reporting it to BMW (dealership service centre) as the auto 'box shouldn't really have done it. I mean if it was a manual, I'd keep my lips sealed, but as the gearbox computer allowed it when it shouldn't have...
It sounds more like your fault than that of the computer.In a manual, you have to actually change gear, and you know when it's been done.
In any auto, often the driver will press the button to down-shift and due to the delay in response from the gearbox, press it again thinking it didn't respond.
This is such a likelihood that any manufacturer would put safeguards in place to make sure this doesn't happen.
It certainly has been the case in my E55 AMG and 911 turbo tip.
Liquid Tuna said:
When you say it went way past the limiter. did you actually hear the revs rise above the limiter, or just see the needle flick past? I realise it all probably happened in a split second, but even so, the revs had to rise and fall again. So are you sure you heard it go past?
This is the thing... I literally picked the car up 3 weeks ago today! (It was a 2nd hand car @ 15k miles, so luckily was well out of its run-in period). Therefore, I am not all that familiar with engine noises of the car at different RPM. Although the engine definitely sounded as if it was revving high, I wasn't in a position to tell if it went past its limiter or not.Sorry to bring back an old thread from the dead, but I think its in the interest of anyone who was following this thread, or finds this thread via google, etc. to know the final verdict.
The tachometer is a bit dodgy. I've been watching it say silly things over the past few weeks every now and again. The engine generally hits 5,500rpm or so at about 30 mph….. and the other day it told me I was doing 6,000rpm when I was doing somewhere between 20-25mph. It also changes its mind sometimes….. for example, I accelerate to join a highway, and once the car has reached a steady speed (and all is steady gear wise, etc.) the tachometer will suddenly change its mind after a few seconds and drop by a few hundred RPM (i.e. not enough to be a genuine gear change).
The tachometer is a bit dodgy. I've been watching it say silly things over the past few weeks every now and again. The engine generally hits 5,500rpm or so at about 30 mph….. and the other day it told me I was doing 6,000rpm when I was doing somewhere between 20-25mph. It also changes its mind sometimes….. for example, I accelerate to join a highway, and once the car has reached a steady speed (and all is steady gear wise, etc.) the tachometer will suddenly change its mind after a few seconds and drop by a few hundred RPM (i.e. not enough to be a genuine gear change).
As an aside, I had an (company car) Ibiza cupra diesel which we were `Gtec`ing` repeatedly at a disused airfield in essex - competing for the best 0-60 time.
The gates for 1st and 3rd were very close together and I watched from a distance as a mate went from 5,200 rpm in 2nd gear to 1st by mistake. The nose of the car seemed to collide with the ground and a Vtec-esque wail was heard faintly over the breeze.
The car made a godawful racket afterwards, felt like driving a cement mixer, enormous vibration, still drove it home 80 miles though... Took it to the dealer and it turned out one of the engine mounts had broken, the block must have been sitting on a chassis rail or something, transmitting all the vibration into the cabin.
Long story short, engine itself was faultless for another 30k miles to the end of my tenure.
The gates for 1st and 3rd were very close together and I watched from a distance as a mate went from 5,200 rpm in 2nd gear to 1st by mistake. The nose of the car seemed to collide with the ground and a Vtec-esque wail was heard faintly over the breeze.
The car made a godawful racket afterwards, felt like driving a cement mixer, enormous vibration, still drove it home 80 miles though... Took it to the dealer and it turned out one of the engine mounts had broken, the block must have been sitting on a chassis rail or something, transmitting all the vibration into the cabin.
Long story short, engine itself was faultless for another 30k miles to the end of my tenure.
sunnydude959 said:
for example, I accelerate to join a highway, and once the car has reached a steady speed (and all is steady gear wise, etc.) the tachometer will suddenly change its mind after a few seconds and drop by a few hundred RPM (i.e. not enough to be a genuine gear change).
This might just be the torque converter locking up automatically as it is more efficient for cruising.Gassing Station | General Gassing | Top of Page | What's New | My Stuff