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Discussion Starter · #1 ·
I've been saying it's normal for some time now, but after driving a few more diesels i'm sure something is up.

My 147 with the 16V 140BHP engine is annoyingly vibrating on idle. I can feel and see the vibration through the steering wheel and dashboard. I noticed that if I unlock my steering wheel using the adjustment lever it stops vibrating, but the entire dashboard continues. It happens both cold and warm and only on idle. Anything over 950RPM is smooth as butter. Besides the vibration, it idles nicely - sounds great - no misfires or fluctuating RPM, it really sounds good and healthy, but it vibrates. No vibration at any speed while moving. Doesn't feel down on power either. Doesn't change if clutch is pressed in or not plus it had a new clutch 1 month ago. I notice the gear level moves backwards slightly when pressing the gas pedal and goes back to normal position when letting go off the gas - no idea if that's related or not.

It has had an upper right engine mount 60662481 replaced as it was torn but that didn't fix it. MAF/MAP have been cleaned. I've been running the car with a maintenance additive every fuel up which should've kept my injectors nice and clean, but I'll have a look with MES for correction values.

What else could be causing it? I was thinking perhaps feeling the engine with my hand in various location to check where it transmits vibrations, but an unsure if that's really a valid test.
 

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According to your info engine seems good, don't worry for little vibration at idle, it's normal because some injector, dmf, engine/gearbox mount etc. Diesel is not full smooth.

I can say I changed all engine silentblocks with 200k km and it was good some months, after there are little steering wheel vibration at idle again, well it's diesel man.
 

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I had the same thing but only after replacing that same engine mount.
I got used to it, and I think it's reduced after a year or so.
Totally agree with ceecao, just drive it don't let it idle and relax 😄
 

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Discussion Starter · #4 ·
I had the same thing but only after replacing that same engine mount.
I got used to it, and I think it's reduced after a year or so.
Totally agree with ceecao, just drive it don't let it idle and relax 😄
Sounds like we need some OEM replacement parts - perhaps new engine mount rubber is too stiff or something. I feel like mine has been getting better, but man is it annoying as hell in my usual start stop traffic 😄 I notice it when its sunny outside and the sun hitting the dashboard makes it soo apparent - at night when I can't actually see it, I don't notice it and feel like my car has been fixed. It's really more of a visual thing.
 

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Most likely the aftermarket quality is bad, yes. I went with Brith brand, but also heard Febi and many others are the same.
Well, you can always take the mount off and you will feel no vibrations. :cool:
But the other engine mounts would disagree and probably wear earlier... Just live with it, it's fine 😄
 

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If you know you can play with remap. Well I had stock dmf, now smf, idle tune there and here. You can get some improvent previous to injectors maintance etc. Stock idle is 850rpm, my smoother and silent seems 830rpm, my easier to drive-start 900rpm.
 

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Discussion Starter · #8 ·
To follow up, I decided to get the car connected to MES to just check over stuff. First of all injector correction values were:
Rectangle Computer Font Line Screenshot


That's on idle and they don't change much when revving the car up to 2-2.5K RPM. Possibly get closer to 0.
RPM is stable ~850, slightly fluctuations 845-855RPM.
Boost pressure and desired boost pressure line up as well.
Fuel pressure and desired fuel pressure line up, no matter the RPM:
Computer Rectangle Personal computer Font Screenshot


I checked the Intake air quantity and this is the only place I saw a difference between both values:
Rectangle Computer Font Line Screenshot


Is such a difference normal? I have the car remapped, EGR blanked off. I read somewhere that blanked EGR causes this kind of behaviour.

I opened the bonnet to see if vibrations seems to be transferred from the upper right engine mount and I didn't feel anything, yet the cover for the engine was shaking visibly, which I don't like - I'd expect it to be more refined.
I noticed though some weird noise coming from the belt area - cam belt was changed give or take a year ago thought. It seems to be a constant noise, couldn't test if it happens when giving gas, as I was alone, but sounds as if a pulley isn't spinning perfectly, but instead meeting some resistance and grinding. At least that's how I'd imagine it'll sound.

So that's all I checked right now, would love some input from you more experienced folks!
 

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Injectors info is normal.

Intake air difference is because you have blind EGR, not problem, 566 mg/i to 850rpm is very good air mass because clean intake + good timming belt set + cold day.

Like said probably side or gearbox silentblock litlle worn, dmf etc. Crankshaft pulley or other can do little vibra when idle too.
 

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Discussion Starter · #10 ·
Injectors info is normal.

Intake air difference is because you have blind EGR, not problem, 566 mg/i to 850rpm is very good air mass because clean intake + good timming belt set + cold day.

Like said probably side or gearbox silentblock litlle worn, dmf etc. Crankshaft pulley or other can do little vibra when idle too.
Thank you for your input Ceecao. I have some car knowledge, but most of these numbers meant nothing to me - thank you for the explanation and putting my mind at ease. The numbers were taken in the morning, first start since I drove the car on Monday.

I have had the alternator clutch pulley replaced previously, but all other pulleys are pretty much original. I feel with an old vehicle I'm really chasing my tail trying to make it perfect as I bet there will always be something wearing out.

My car will be serviced next month and I might ask them to have a look on these mounts, but honestly, if they're too expensive I might just put it off for now since the MES numbers are fine, this vibration is more of an annoyance than a problem.
 

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Sounds like we need some OEM replacement parts - perhaps new engine mount rubber is too stiff or something. I feel like mine has been getting better, but man is it annoying as hell in my usual start stop traffic 😄 I notice it when its sunny outside and the sun hitting the dashboard makes it soo apparent - at night when I can't actually see it, I don't notice it and feel like my car has been fixed. It's really more of a visual thing.
It might be worth slackening off the 2 nuts that hold the heady-steady mount to the RH suspension turret, then tighten them up again. The mount has slotted holes, and if wrongly positioned may be compressing the mount rubber and feeding more vibration into the body. Loosening a couple of turns, then re-tightening should allow the clamp to set itself to the best position.

I can certainly feel a little vibration at the steering wheel at idle, but it's regular as a watch and not intrusive - just diesel. Wear in the damper pulley on the end of the crank might make it worse - the rubber that isolates the pulley outer from the centre deteriorates with age. I replaced mine 5 years ago, prematurely - it wasn't as bad as I thought. Eventually they get very noisy from metal to metal contact, could be mistaken for big ends. My nasty noises were elsewhere, 2 bent valves from ingested swirl flaps.
 
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