help, shudder from idle to 2500 rpm

eunos · Postby **eunos** » Fri Jul 03, 2009 9:01 pm

Just got the car back from a service where I was told the leads and plugs were in perfect condition. I asked to have the throttle cable tightened, but this wasn't done so I popped under the bonnet and just did it myself it's not a tricky job, undid the locknut, took most of the slack out of the cable and redid the locknut. Went out for a drive to discover the car shudders at around 1900-2200 rpm no matter what gear, even when the clutch is in. It doesn't happen on very light throttle (or if it does it's undetectable) but when there's say 20+ % throttle the car will shudder.

I'm about to go and loosen the cable a little to see if this makes any changes, but something tells me that's not going to fix the problem.

*edit* car is a 93 NA8 clubman

wun911 · Postby **wun911** » Fri Jul 03, 2009 9:05 pm

the shudder shimmy whatever you call is a known issue its on the big forum a lot.

eunos · Postby **eunos** » Fri Jul 03, 2009 9:12 pm

Just back from re-adjusting the throttle cable which changed nothing and I now noticed that the shudder happens from idle all the way till about 2500-3000 rpm

I've done a quick bit of reading wun, are you talking about the 100km shimmy? or the clutch shudder? this happens in all gears and when the clutch isn't engaged so I'm fairly sure (although will happily stand corrected) it's not going to be related to the clutch or 100km shimmy. It seems as if the engine itself is shaking as opposed to anything else on the car...

Old Dude · Postby **Old Dude** » Fri Jul 03, 2009 9:17 pm

Check your sparkplug leads, air filter in case they left a rag in or something ( happened to me once)
Regards
Old Dude

Old Dude · Postby **Old Dude** » Fri Jul 03, 2009 9:21 pm

Also sounds like you might be getting too much fuel/ not enough air ( running rich), maybe give the guy that serviced it a call tomorrow and get him to fix it...!!!
Old Dude

eunos · Postby **eunos** » Fri Jul 03, 2009 9:38 pm

Cheers old dude, didn't think something might be in the airbox. Another point about the clutch shudder issue is that it's reported to only happen when cold and this is happening when the car is warmed up.

Nothing in the airbox (filter aside)... bollocks.

Any other ideas? haha

mxfive95 · Postby **mxfive95** » Fri Jul 03, 2009 9:40 pm

Could also be a worn or broken engine mount. i'd definatly be taking it back to the mechanic. Alternativly you could hire a midget or that little bill guy from the toyota addvert and squeze him in there while you drive :lol:

project.r.racing · Postby **project.r.racing** » Fri Jul 03, 2009 9:55 pm

ignition issue of some sort.

plug or leads.

Old Dude · Postby **Old Dude** » Fri Jul 03, 2009 10:01 pm

Eunos
I have had the clutch shudder and it only happens when you start off, and if you have higher revs when you start off that normally gets around it,( its glazing of the flywheel that causes the shudder and if you slip the clutch a bit you get rid off the glazing and the shudder goes for a while) the shudder doesn't happen in 2nd , 3rd etc
It would be worth talking to the servicer though
Regards
Old Dude

wun911 · Postby **wun911** » Fri Jul 03, 2009 10:06 pm

Ive have similar symptoms, when I took my old flywheel out it was glazed and burnt in an uneven pattern. I got the shudder sepecially when taking off in the wet.

New clutch is in and everything is dandy...

Alex · Postby **Alex** » Sat Jul 04, 2009 1:35 am

I would be checking the airflow meter connections.

GP14 · Postby **GP14** » Sat Jul 04, 2009 1:47 am

i'm assuming it wasn't doing it before the service? If that's the case what was done on the service, then maybe we can narrow it down for you where they may have adjusted something wrong.

eunos · Postby **eunos** » Sat Jul 04, 2009 3:17 am

Cheers for the suggestions all, please keep them coming anything you could think of that might be the cause.

atm I'm leaning towards something to do with the AFM, 02 sensors, possibly intake butterfly/s or a dodgy engine mount (but the engine mount doesn't make sense as it stops after around 3000 rpm)...

A few further points after reading some responses:

-the problem occurs when taking off, accelerating in gear when I let the revs drop below 2000 or so and with the clutch depressed (which leads me to think it's not going to be something in the transmission/clutch/flywheel but I'll be mentioning it to the mech all the same)
-The problem gets worse the more the throttle is applied. So with a little bit of throttle there's a little bit of shudder, more throttle = more shudder
-Perhaps describing it as a shudder is the wrong description, it feels like power chopping in and out (I'll throw up a video tomorrow which will hopefully remedy any shortcomings of my description).

The service was just a general oil,plugs and filter and fix some specific things namely:
-Rocker cover gasket (there was a small leak)
-2 heater hoses
-clutch slave cylinder + clutch fluid

It wasn't doing it prior to the service that I had noticed, but before the service the throttle cable was loose.

My thinking is that as the problem really only present with more than light throttle as the cable was loose there was never enough "juice" being given to the engine at the revs in question to really show up at all. But after the tension was fixed the engine is getting more throttle at low revs and the symptoms are showing up.

My gut feeling is that the cause of the problem has nothing to do with the throttle cable itself or really anything that happened during the service (unless there was some complication with the rocker cover gasket???) but that removing the slack and possibly the service has exacerbated the problem.

Steampunk · Postby **Steampunk** » Sat Jul 04, 2009 11:46 am

so it doesn't feel mechanical at all?
I was going to suggest that the grease monkey may have loosened a bolt on the drive-shaft and forgot to do it up, but if it's not a mechanical issue and you think power is being robbed and is inconsistent, then the first thing I would do is simply replace the spark plugs and leads.
Even if they look ok, they may not be internally.

Spark plugs are cheap and easy to replace, and I'm sure you can borrow a set of leads from someone on the forum nearby.

Before you do anything, maybe drive it for at least 20minutes and give it a boot-full, revving it past 5,500RPM in each gear as often as you dare as maybe they sprayed some degreaser or fuel cleaner in your manifold or fuel lines and it hasn't cleared.

GP14 · Postby **GP14** » Sat Jul 04, 2009 6:07 pm

Does it feel like its running on 3 cylinders? If it is it sound like a similar problem I had with my leads. It would do the same up until i was over 3k revs as well. This problem hit me out of the blue with no warning. Mine were arcing to the engine with no visible signs of cracks on the ends. I would suggest taking the leads and spark plugs out and put them back in yourself just in case they were not seated properly. How does the guy know the leads were in perfect condition? did he do a resistance check or arc test? how old are they? If you can borrow someone's leads and do a test that may prove of disprove that theory.

cheers