Hello all,

 

I've been closely following this thread -> http://www.briskoda.net/forums/topic/361464-fixed-vrs-idle-shake/

 

My VRS (ASZ) has been shaking on idle for over a year.  It's not a constant shake though, but every 5-10 seconds you'd feel a jolt if sat in the car.  Similarly, you can see the engine do this if you leave the bonnet and the revs also tend to fluctuate very slightly when this happens.

 

The Low-down

 

• New Luk Clutch & DMF fitted 21 months ago.  I think this does make a 'rubbing' sound
• Rear engine mount needs replacing as with force I can move the engine by hand a little (but don't see why this would lead to an erratic shake every 5-10 seconds or so)
• Injector values look fine at idle and 2300RPM in neutral
• Timing looks fine (fluctuates between 0, .6 and 1.1)
• No fault codes logged

 

So...I'm wondering if I've also got the PD camshaft/lifter wear issue.  Car has done 165K with excellent service history and I have changed every 5K myself for the last 30K with PD oil.  However looking at these other threads, service history doesn't seem to guarantee unworn lifters.

 

I've attached a video but as luck would have it, the shake on idle this morning wasn't hugely noticeable so the video isn't a lot of good.  It usually really jolts forwards noticeably.

 

I know this isn't normal as it never used to do this, nor do any of the PD100s in my family do this.  Any thoughts on this would be appreciated.

 

Thanks, Dave

 

Injector Idle Values

 

Injector @2300RPM Neutral Values + Timing

 

 

Attempted video of shake on idle

https://vid.me/GOhH

Edited 31 October, 201510 yr by Dave89

Try resetting your injector lash. If you have wear then these would need to be reset anyway. Worth a shot, and it's an easy 30 minute job. Apparently there's a new setting to try, i.e. 180 degrees back turn.

 

I'm sure I've heard someone say that they are designed to sound a bit rough on idle though. Something to do with emissions or something...  Someone will be along to clarify hopefully!

I'm not sure I think there is anything wrong with the engine movement in that video? Doesn't look bad to me at all. Is that it at its worst?

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This was my rough idle! Lol

http://s1330.photobucket.com/user/Ash_Frost/media/Mobile%20Uploads/20150705_164945_zpsrd9v7wkf.mp4.html

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Ash mine is just like yours :/

My followers were showing some wear and I had slight flat spots on my cam lobes. I swapped the lot out for new stuff and it behaves itself an awful lot better now. My car has full skoda service history up until I bought it also.

You can see one of the old followers against one of the new ones below

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Was it a big job ?

How much were cam followers to replace (part only) also is it worth replacing anything else in the process?

Yes it was a fairly big job for me as I'd never done it before. I did it all over two days in the end.

You can't just replace the followers if your camshaft is showing signs of wear as it will just wear the new followers unevenly. I replaced the camshaft as well.

Then also the shell bearing for the camshaft along with the associated bolts.

I also did the cam belt and waterpump at the same time.

I think it cost in the region of £300 to buy all the parts but then there was a few tools I didn't have, along with things like assembly lube and sealant so was no more than £375 I rekon.

If I were you I'd start by removing your cam cover and seeing what you can see.

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I did plan to have the camshaft/followers/bearings/head bolts/waterpump/cambelt all done if this is going to be the cause.

 

Frustratingly, the car was 'behaving' when I took that video.  Normally, you can see the hoses flexing a good 1cm in distance when it goes for a real shake.

 

I'm just trying to self-diagnose rather than paying a lot of money to diagnose, only to be told what I expected since the car is worth so little now but has had thousands spent on maintenance and want to keep it running well.

 

"Try resetting your injector lash. If you have wear then these would need to be reset anyway. Worth a shot, and it's an easy 30 minute job. Apparently there's a new setting to try, i.e. 180 degrees back turn."

I'll research into that as currently not sure what that means... anything is worth a go however!

 

Ash - Your video is how mine can be when really erratic but not so frequently.  Sort of confirms in my head that this is the issue, although wear might be minimal at this stage.

 

How did yours drive out of curiosity?  Did you notice any different sound or willingness to 'go' below circa 2300RPM?  Not sure if I'm imagining this or not.

Funnily enough mine didn't behave like that all the time either. Sometimes it would tick over fine, there was no predicting when it would start ticking over and shaking like it is in the video.

Other than shaking the car to death on idle the car performed fine though. No rough starting, or misfiring, or lack of performance.

Although my followers were showing signs of wear, my camshaft wasn't too bad so I think I caught this at the right time.

Here are some more pictures of what I took out. Probably not the end of the world but certainly some wear evident

I've circled a flat spot which was visible on one of the cam lobes in the next picture

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