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Yesterday driving home i went to take off at the lights semi hard, reved to bout 2k and released clutch and took off, first gear reved to bout 5k, into 2nd got up to bout 3k n the car violently shuddered, not just a flat spot like a fuel pump overload. It sounded like the car was boosting but didnt have the power. i drove home the rest of the way not reving over 2.5k n trying not to boost it up. Worked fine. Just took it for a drive to work out the problem. It was fine in 1st gear but in 2nd, 3rd n 4th after about 3000 revs it shuddered violently again. It similar sound n feeling to when you bunny hop the the car not having the revs up when releasing the clutch (like learning to drive manual). The car has only a manaul bc which is set to about 11psi. Every thing else is stock. Anybody know of what the problem may be.

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violent shuddering happend to me once when a coilpack went out and the car was running on x amount of cylinders

could be coil pack, spark plug or injector etc or mayb something is blocking a particular cylinder in the plenum

I took off quick, didnt dump the clutch. I honeslty cant tell if its drive train related or not. I changed the spark plugs 2 weeks ago, gapped to 0.8mm. The shuddering sound comes from the back of the car but it feels as though the problem starts in the front of the car, engine related. If it was the clutch, wouldnt it just free rev? There isnt any clutch smell.

feel the engine on idle for any shudders, then rev with your fingers on the tb and feel again.

if there is, try pulling a coil pack out one at a time to see if there is any change in engine note,shuddering. if you pull onw and there is no chnage then that cylinder is probably not firing properly

this happnd to my beema, i ended up finding the bad coilpack n changed them all.

and as i drove it, 1st n 2nd gear didnt shudder but at 3rd when the engine was on higher loads, the engine was out of balance and vioently shuddering.

might not b the prob but it was for me so jst offering input.

I took off quick, didnt dump the clutch. I honeslty cant tell if its drive train related or not. I changed the spark plugs 2 weeks ago, gapped to 0.8mm. The shuddering sound comes from the back of the car but it feels as though the problem starts in the front of the car, engine related. If it was the clutch, wouldnt it just free rev? There isnt any clutch smell.

Mmmm shuddering @ the back, but feels like it's starting in the front.

So something that runs from diff to engine, gearbox and tailshaft. Check universal joints, when they're on the way out it feels like all hells breaking loose from front to back. You will be able to get them checked for free at most brake/clutch/suspension type places if you don't know what to look for..So if it's not the prob no loss :bunny:

Edited by madbung

My assumption was that all skylines have a small idle shudder, the revs bounce up n down a little but not enuf to show on the tacho, mine does that n has for the last 2 years that ive had the car. The car had a minor surge under power a few weeks ago so i changed the spark plugs and that seemed to fix it, untill y'day. Ill pull them out 2moro and have a look at them to see if any of them are rooted. I think ill give everything that i can clean a big clean as the engine bay is fairly filthy at the moment.

The thing is in the last few months ive a had a heap of little bugs go wrong in the car such as i have something draining the power from my battery that an auto elec couldnt find, this surging before i changed the plugs, my drivers side window switch is knackered so putting the window up n down i have to twist some wires together n reverse them to make it go up n down, then they all touched the other week n now the drivers window wont work at all, i think ive blown the relay. 6 week wait n 400 bucks for a replacement part from japan. Ive just saved up enuf money to do a heap of engine mods but now ill have to use this money to get this other stuff fixed. The car is playing up with me n its hard haveing a nice car that doesnt work properly, my fiancee is getting pissed of with me cos every week it feels to her there is a new problem with it.

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