Hi Guys,
For those who don't know, I had an issue a few days ago with my Auto box on the MV6, constantly going into limp mode after gear changes, and on a couple occasions, causing a shaking from the autobox.
The code logged was P0748 - Automatic Gearbox Pressure Control Solenoid open circuit.
Having checked the security of all the electrical connections, next step was to take the sumps off for a look (praying there were no remains of thrust washers inside them!!)
I first removed the front gearbox sump, this afternoon. Apart from the (expected) brown-ness of the oil (130,000 miles), it was remarkably clean inside with no bits present. So the Thrust washer is intact!!
I then removed the pressure control soleniod, which is the component the fault code related to. Not too tricky, just held in with a little bracket that slots into the groove. If any of us are doing just an ATF change, it's well worth noting that upon removal of this solenoid, a LOT more ATF came out of the apeture than was just in the sump. I know we like to get as much out as possible!)
Anyway, here is the old, original one, which I removed.
I didn't re-fit it, as I had a new replacement, from JPAT (£40, if ever anyone needs one).
So - replacement solenoid in, wires connected to it, and front sump back on.
Ususal drill then followed for removing ATF, and gearbox re-filled using some nice new Red stuff
The result?
Well, before, I couldn't get to the end of my road without it dropping into limp mode. This afternoon, (after a short trip to settle/recheck ATF level) - and a shower to get the ATF out of my hair - I did a very enthusiastic drive of about 20 miles on some A roads, lots of sport mode/kickdown - using the gears lots and really having a good time! No limp mode, no ill effects
So - as it stands, I'm pretty confident the issue is fixed, and that the problem was the pressure control solenoid in the autobox.
Some will also remember I have mentioned in the past that I had a high-pitched whine from the gearbox, when listening to it stood outside the car, with the engine idling? This has now also completely gone, so I can only attribute it all to that solenoid.
Also - I'm not sure if this is just placebo effect, or if it's a result of the new solenoid/ATF, but, for some time I've felt the car is a bit flat. Well, after doing this job, it does seem a lot more responsive to apply the drive, gearchanges are better, it generally feels a lot better to drive.
Codes cleared - none returned.
Figers crossed
- and thanks to everyone for the various suggestions/opinions
Am only posting this in it's own thread because I don't think I've seen this issue crop up much / be related to the solenoid, so hope it might be some use in future, when people with the same problem run a search.
I'll update in due course as to whether it's still behaving.
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Topic: 3.2 MV6 Autobox / Limp Mode Problem - The Culprit (Read 2550 times)