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hi i have a small issue with my r33 gtst. running 250bhp (186kw)

when driving along at ANY (even at 80 or 90mph) (128 or 144kph)speed and holding it at a set speed its like it drops in and out of overdrive but as soon as i come of the throtle and back on it or press the throtle it gose back to normal till it dose it again.

i have done a system check via the power button light and i got 1 long flash followed by 10 short flash so there seems no faulf on there and the atf level is ok and no burnt smell.

this is confusing me and i want to get it sorted as i have mv auto's valve body for it but dont want to put it in if the box is knackered

any help apreciated please

Edited by wolf
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Does the O/D OFF light on the dash also intermittenly flash on & off?

It's mostly likely to be electrical. Remove the shifter surround console & visually check the O/D button & along its wiring for any loose/ damaged connection. Then test it using a 12V test light or a multimeter on the O/D switch wire.

Otherwise you may have very low line pressure which can be casued by a number of things but, cleaning the ATF filter may help.

If neither of these are the case give Mike from MV Autos a call as he'll be more than happy to help you out.

  • 2 weeks later...
hi i have a small issue with my r33 gtst. running 250bhp (186kw)

when driving along at ANY (even at 80 or 90mph) (128 or 144kph)speed and holding it at a set speed its like it drops in and out of overdrive but as soon as i come of the throtle and back on it or press the throtle it gose back to normal till it dose it again.

i have done a system check via the power button light and i got 1 long flash followed by 10 short flash so there seems no faulf on there and the atf level is ok and no burnt smell.

this is confusing me and i want to get it sorted as i have mv auto's valve body for it but dont want to put it in if the box is knackered

any help apreciated please

Are you running an aftermarket computer? If you are, almost no models come with a shift controller for an Auto box, as a result, the ride will be ragged an unpredictable. They basically run maximum line pressure, rev it up and just whack her in gear whole doing funny things with your O/D. Best thing if you're running an aftermarket computer is to purchase a separate shift controller unit and install that on the car so it has the smarts to deal with the auto box.

Are you running an aftermarket computer? If you are, almost no models come with a shift controller for an Auto box, as a result, the ride will be ragged an unpredictable. They basically run maximum line pressure, rev it up and just whack her in gear whole doing funny things with your O/D. Best thing if you're running an aftermarket computer is to purchase a separate shift controller unit and install that on the car so it has the smarts to deal with the auto box.

nope i have the standard ecu and no other add on computers

i did do an ecu reset and was fine for a few days then came back

  • 3 weeks later...

i have a similar prob. it also happens when cruising at anywhere above 80kph. the box just drops into overdrive and refuses to shift up. sometimes it seems to do it less if im in snow - which also seems to make it shift up sooner. i have tried completely coming off the throttle but it does nothing positive. i have to rev it hard in 3rd to maintain speed. once i clunked it into neutral and back to drive. seemed to do the trick but only that once.

i have a similar prob. it also happens when cruising at anywhere above 80kph. the box just drops into overdrive and refuses to shift up. sometimes it seems to do it less if im in snow - which also seems to make it shift up sooner. i have tried completely coming off the throttle but it does nothing positive. i have to rev it hard in 3rd to maintain speed. once i clunked it into neutral and back to drive. seemed to do the trick but only that once.

yep but what i have found is when i do an ecu reset it goes for a few days. also when it does do it i now give the accelerator a bit of stick and it goes and stops doing it till next time the car is switched off. but got mv auto's valve body a new filter and oil for it so see if that cures it

  • 2 weeks later...
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