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147 1.9 JTD vibrations on idle - again

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vibrations
21K views 26 replies 9 participants last post by  coasamihai  
#1 · (Edited)
My Alfa 147 1.9 JTD 8v run very well, but...
I have vibrations (inside in cabin) on idle (about 850rpm)... On higher rpm all is OK. I changed all four engine mounts and made reparation of all injectors, but vibrations remain.
I perform engine balancing (release and fix of engine mounts screws when Alfa was in idle) and think that problem is gone, but vibrations appear again...
Besides, I have rough engine work in start and acceleration.
What is the problem?
 
#3 ·
I suppose those vibrations in my case are caused because improper rubber quality (for cold weather circumstances) in engine supports... For your Stilo JTD main reason for vibrations is engine support near to the gearbox. You can try to change this support.
 
#14 ·
Put car in neutral and then push clutch pedal. If vibrations stay the same no matter if you clutch is pressed or not, then it is not DMF.
There is no difference.

My story in short:
I bought the car, the clutch started slipping, went to local garage to replace it.
When they took it off, it was a 230mm clutch with a 230mm DMF, both used in Fiat's JTD105.
Yep, bad luck, i know ....

I bought an used DMF from Stilo 235mm and a brand new clutch Valeo 235mm and the vibrations appear.
Also when slowly accelerating in 4th and 5th gear from 1200rpm to 1500rpm, there are very minor vibrations, felt mainly on the steering wheel. Passengers can't feel them.

That's why i'm blaming the DMF.
 
#22 ·
Hi. I've been having the same problem for last couple of months, went through everything, got injectors leak off tested, checked engine mounts, checked power steering fluid, checked drive shafts all ok, changed MAF(mechanics ÂŁ250 hunch :rolleyes:), I give her full pampering(engine flush, new oil and all filters replaced, removed cleaned and blanked the EGR, added Redex to fuel) all had no affect what so ever,
My mechanic -"Alfa Romeo Specialist" tried to convince me the vibration was in my head... :(

I plugged her in to MultiECUscan after buying interface online, injector correction values were off the scale at idle +2 but went back to almost zero at 2000rpm.
I took her back to mechanic to redo the leak off test again he found nothing wrong.
I decided to take it on myself and removed the injectors and took them to independent diesel tester who bench tested them, all four were out of spec. He said it may not have been picked up by leak off as all injectors were returning similar amount of fuel all be it too much...

Long story short, Plug in to Multiecuscan and check correction values, this will highlight if injectors are at fault, if in doubt remove and get bench tested. Don't be shocked if all four are done as my car was driving fine with plenty power with the exception of vibration on idle which started suddenly and it was a bit smoky on start up.
 
#27 ·
Hello guys. I have my alfa 156 1.9 jtd 85 kw from 1 year and i have some vibration on idle. I change the DMF and clutch because the vibration was big when i start in 1 gear. What can be the cause of the vibration? Cambelt is new, engine pully new, alternator pulky new, alternator belt and tensioner new, engine mot from gear box new and engine mout close to shock absorber is the same new. And one more thing: when i drive for example in 4th gear if i leave the gas pedal fast and push again i hear som clanc/clanc....
Any idea is very good for me so please little help....