Auto gearbox problem I think

[kika]

Hello all. I have been a daily reader of this forum since April when I purchased my 2011 X5 40d, a fantastic vehicle that makes me smile every time I get into it. Up to this point everything has been great, but last night whilst making a long trip home a very peculiar thing happened. I was pushing the vehicle a little shall we say across some very nice double carriageway A roads when I pulled out to over take only to find no power. A bit scary. The vehicle would kick down, revs increase, but it seamed like the torque converter wouldn't transmit the engine power through the box to the wheels. At low speed it drove fine and would accelerate gently ( normal driving) but if I wanted to boot it the vehicle dropped gears but only very slowly accelerated. After stopping for 15 mins and restarting the journey all was ok. It is a very strange event and I will book it in to be looked at, but was wondering if anyone had any ideas what this might be. I thought perhaps a temp safety in the gearbox, but does seam odd.

[X5Sport]

Any warning lights or messages on the iDrive?  Anything showing on the 'Check Control' functions?

Not heard of that before on the 8sp but be interesting to see what the Dealer finds - assuming an error message was logged - when you take it in.

I would have thought that you would need to be absolutely caning it for a long while for the temps to get too high and then you would get an overtemp limit warning come on.

Richard

[kika]

I was pushing it, not caning it, nothing more than enthusiastic driving. No error messages on the idrive or on the system check.

Chris

[X5Sport]

That's what I thought you meant..... . 'Caning' would be in an Autobahn at full speed, or on the M62 in a hired R8 - like that idiot who was caught for 165mph!!

If the box is changing gears then it might be the xDrive unit not working.  The 8sp box is not yet known to have anything like the issues that the old 5 & 6sp boxes had.

The only issue reported on this forum was a failed electronic rear axle system on an X6.  You don't have this system fitted on the E70 so it's not that.

Richard

[kika]

Well, unfortunately the dealer found nothing. This is the worst kind of problem. You know it is there waiting to happen again, but leaves no trace.

[X5Sport]

Well no trace that the partly competent BMW Techs can find anyway!!  They need the computers to tell them where their *rses are half the time!!

The thing is, it's logged and they should have it on the notes for the car so if it does it again you can go and say 'told you so, now fix it!!'

Richard

[kika]

Thought I would post an update.

No further problems from the gearbox. Can only assume it was overheating or some glitch in the software.

Managed to scrape rear wheel arch couple of weeks ago, but luckily getting it done under warranty while they fix the rear arch shot blasting from the front wheels problem.

Chris

[Drpellypo]

My Audi box did this once. That was two years ago. Never happened again. I can only assume the ECU's have a funny turn then right themselves.

[kika]

Well it has just done it again. We got stopped on the motorway today under a controlled stop. When I started away it changed down made all the right noises, but no acceleration. It's as if the torque converter won't pass the power through. When it reached top gear it pulled fine. As soon as kick down no power. Booked in again next week. I hope the fault doesn't clear this time. Annoying.

[X5Sport]

Have you still got BMW Assist/Breakdown cover under the original warranty?  If you have then call them out.  They usually turn up in a 5 series with all the same computer kit as a decent dealer and you can talk them through the issue as it happened.  These guys are techies, not service drones, so you can describe exactly what happened and how together with what you felt and heard.

Richard

[kika]

Update. Problem solved

So the BMW garage diagnosed that I needed a new inlet manifold. This was fitted last week. When I collected the car it didn't feel right and I decided to take it back. The very next morning the fault recurred only this time an engine fault warning showed up with reduced power. I took it to the garage immediately and they diagnosed a faulty inlet seal. This has now been fixed.

Car runs superb. In fact when I purchased the car about a year ago I always felt that for a 40d it didn't feel much better than my previous 30d. To get any real performance I needed to use the box in sport mode. Well the fault must have been giving reduced power all along because now it goes like a scalded cat. Very happy.