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I get this when backing off the power, say, at 120 on a hill when it's under load. Sometimes on the level too. Is this something to be concerned about? Likely cause?

Much obliged a p u.

No idea (sorry to disappoint), but mine has started doing it too. Only when travelling at 110kph or more. If I sit on 100kph, I don't have the shudder.

No noise, sort of feels like the engine leans out. Very weird.

I am not 100% sure that it s transmission as it feels like it is coming from around the front axle... perhaps.

Anyone else have this or know about it?

  • 2 months later...

Is your car still shuddering?

I had a wheel alignment when I got my LMX5's last month which did not help the situation.

I took it to Nissan who put their "magical" satchel in when they did a full service on the transmission, snappier gear change but no change to shuddering.

Nissan also did an ECU reset, again, no change to shuddering.

Frustrating!

Anyway, I had my exhaust & front pipe installed on Saturday and also changed the spark pugs.

The shudder seems to have gone completely, even when cruising at 130kph for half an hour!

Don't know which one fixed it (touch wood), but it has definately settled down (not to mention become MUCH more lively and quite a bit quicker :( ).

Edited by iamhe77

I guess I didn't touch enough wood (refrain from the "wood" jokes).

The shuddering is back again this morning but only for a short time.

....Frustrating as all hell.

Nobody seems to know what it is.

Will check tonight IF I get time & daylight (unlikely).

Quick question, if air was being pushed back into the turbo when lifting off the accelerator, would it make a noise or shudder?

(just a theory a friend of mine had).

Could b a number of things...have u checked engine mounts...worn or damaged mounts can cause the engine to move on acceleration or deceleration. Excess gear backlash (the amount of freeplay between the gear teath when engaged)...this can mean a worn box...same can happen for diffs.

though with such a new car...this shouldn't b the case...though its probs worth a check.

+1 for checking engine and gearbox mounts.

also the turbo will make a flutter sound and not shudder with that condition and wouldnt affect the entire car like that. BUT with the air surge, this may affect the AFM metering and might make the engine shudder if it gets more fuel that its supposed to. maybe check the factory BOV is working. block up the return pipe (with something you can again remove) and see if the prob is still there. but id be checking other things first.

Well here's one for you.....does your make a slipping/farting sound at maximum torque(3,500 to 4,000rpm's)?....I also get a slight vibration but it's only under maximum power from about 110km's onwards......sort of feels like the front wheels are trying to get tow out.

weird i know...never had that experience before in anything....lol.

P.S. and know I don't drink or smoke weed while driving!!!!!lol

Well here's one for you.....does your make a slipping/farting sound at maximum torque(3,500 to 4,000rpm's)?....I also get a slight vibration but it's only under maximum power from about 110km's onwards......sort of feels like the front wheels are trying to get tow out.

weird i know...never had that experience before in anything....lol.

P.S. and know I don't drink or smoke weed while driving!!!!!lol

Nope, no noise when it shudders. Just drops power/revs briefly.

Having said that, I have had a couple of instances under full boost where it would sound like I have a hole in the muffler.

As soon as I let up it goes away & doesn't come back if I get back on the power... weird huh? Would this be similar to what happens with yours?

+1 for checking engine and gearbox mounts.

also the turbo will make a flutter sound and not shudder with that condition and wouldnt affect the entire car like that. BUT with the air surge, this may affect the AFM metering and might make the engine shudder if it gets more fuel that its supposed to. maybe check the factory BOV is working. block up the return pipe (with something you can again remove) and see if the prob is still there. but id be checking other things first.

+2 on engine mounts, not sure if it works with auto trans cars but with a manual you can check the flex by pulling the handbrake hard on, reving the engine and dipping the clutch to apply load to the motor while someone else (mechanic) observes how much the engine twists in the bay. Someone else here might be able to clear this one up.

re: turbo, If the BOV is blocked you'd notice it because you'd be getting the distinct flutter sound. I doubt this would affect the AFM enough to make the whole car shudder but it might increase the chance of the engine stalling at low RPM - my Stag used to stall after a small rev with the BOV blocked off but it never used to shudder.

  • 5 months later...
No idea (sorry to disappoint), but mine has started doing it too. Only when travelling at 110kph or more. If I sit on 100kph, I don't have the shudder.

No noise, sort of feels like the engine leans out. Very weird.

I am not 100% sure that it s transmission as it feels like it is coming from around the front axle... perhaps.

Anyone else have this or know about it?

new to the forum but mystag vibrates at around 4500-5500rpm i think it is the viscous fan if you watch it and rev the car you can see it it also goes away afther about 5500dont know if it is the same thing but worth a trywhen not moving you can bearly feel it in the car only when driving

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