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R34 Shuddering In Drive.

picklesRs4
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picklesRs4 Community Regular

picklesRs4

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Hi all, I recently replaced the turbo in my car with a high flow (no supporting mods yet) and have got the car running smooth on idle with no vad noises. Drove it out of my driveway and back in pretty much just to swap cars around and noticed as soon as the cars in drive at idle there is a shuddering that goes through the whole car, it doesnt try and lurch forward like it would with a wrecked converter tho, just shakes until I put it back into neutral or reverse.

Anybody had this problem before? Any ideas appreciated,

Cheers :)

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picklesRs4 Community Regular

picklesRs4

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Sorry if its not what you meant by "what revs?" But idle is set to around 900, when I re installed the turbo I double and triple checked all the vacuum lines had somewhere to go but I broke one at yhe rear of the motor and super glued it back in place, possible cause? I know theres an empty place for a vacuum line onbthe block near the turbo but it seems to be one for a line off the manual boost controller which doesn't reach there. Other than that all lines are in place

Duncan Grand Master

Duncan

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sorry I think I left a few words out of that sentence.... I meant to say, what revs does it idle at in gear (generally lower than neutral in an auto, and turning on the aircon should raise the revs)

but anyway I think you found the problem, any vacuum nipple without a hose must cause a leak. if you put your finger over it when the engine is running can you feel it sucking, and does it start to idle higher? If that is not the leak you might also have a small split in one of the hoses (very easy when removing and replacing brittle stock hoses, so double check everything. also check all the hose clamps that you had to undo on the intake to fit the turbo

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