Strange judder when decelerating

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Strange judder when decelerating

Postby 101_fun » Thu Mar 30, 2006 5:50 pm

I have had a search through the database, and have not been able to find anything so I apologise if this has already been done in another thread.

I have an AE101 Levin 20v Silvertop, and all in all it runs very well and is well maintained. There is one bug-bear I have though and the symtoms are this:

When I am above 5000 revs (mostly noticable in 3rd or 4th) and I start backing off the throttle, the car starts doing this little *judder*, almost as if theres intermittant fuel pressure or something. Its not real bad, and it disapears as soon as i even lightly depress the accelerator.

Mods are very basic - 2 1/2 inch pipe, cat removed, TRD panel filter, Jasma muffler. (as it came)

I do wonder if it could be fuel pump related - There is an occasional whiff of petrol inside the car when driving sometimes, although I have checked the pump under the rear seat and no leaks are obvious. (It *could* just be unburnt fuel coming out the back that im smelling...)

Any ideas?

Thanks.
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Postby B1NZ » Thu Mar 30, 2006 6:43 pm

engine mounts ok? my fxgt had a shudder which developed into more of a clunk recently
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Postby 101_fun » Thu Mar 30, 2006 6:46 pm

Hmmm hadn't thought about that. I wouldn't know where to start investigating that one...is there a simple test?
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Postby Bling » Thu Mar 30, 2006 6:48 pm

get a torch and check the rubber on the mounts attatching the engine to the car are sweet would be a good start
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Postby 101_fun » Thu Mar 30, 2006 6:57 pm

I would have thought that if it was engine mounts it would be showing up more often, and under acceleration as well as deceleration....

Still - can't hurt to check. Ta.
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Postby slighty_sykotic » Thu Mar 30, 2006 8:06 pm

TPS sensor...


I'd guess that.

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Postby matt dunn » Thu Mar 30, 2006 10:38 pm

slighty_sykotic wrote:TPS sensor...


I'd guess that.

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Postby 101_fun » Fri Mar 31, 2006 2:59 pm

Ok so I have checked the engine mounts that I can see - they look fine as far as I can tell. Also the problem really doesnt feel like the engine itself moving around, rather a judder coming through the drive system.

TPS sensor makes sence, but I don't know what can be done to prove this. Is it a case of adjusting it somehow? Or is it a replacement jobbie?

Little help?
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Postby slighty_sykotic » Sun Apr 02, 2006 2:48 pm

There is a post somewhere by HRT I think that lists the specs of the tps sensor. You basically measure the resistance of certain pins, and you can adjust it a little bit by undoing screws and twisting.

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