Bearing Noise From Engine Bay

[Seatdriver]

Hi its been a long time since I have posted on this forum but I may have a problem with my 55 plate 1.9 tdi 130 Alhambra.

It has just been in for its cam belt change at 4 years old, main Seat Dealer, full kit fitted. It has only covered 27000 miles.

The problem is that if I rev the engine to about 2000-2500 rpm quickly and lift my foot off the throttle I can hear a definate whirr whirr whir sound (like a dry bearing) from the top left of the engine that quickly disappears as the revs drop to idle. I can also hear this sound faintly inside the cabin when accelerating and changing gear. If I rev the engine slowly to 2000-2500rpm and let the revs even out and slowly die the sound does not appear to be present.

Now the car never gets a good long run, spends most of its time being driven round town, engine registering cold.

I have checked the obvious ie press economy to turn off A/C and listen to the compressor. No noise so to speak other than hearing it come onto load when I press AUTO. The whirring noise is the same clutch up clitch down when revving the engine, put my ear to the gear knob and only a very very faint whirring sound can be heared which I would expect.

Rev the engine to 3000rpm and the sound doesn't seem to be present when engine revs drop.



Penny for anyones thoughts

[big wheel]

That was a good desciption word for word of the same thing mine does.
I have an 05 tdi Galaxy and will be very interested in any reply you get.
I think modern cars are like computers, you fix one problem and the next time you start it up, there's another problem for you to fix.
Bring back the simple cars like the old Cortina, no electric windows or door mirrors, a timing chain you never replaced, a fan belt for two quid, a set of plugs and points, and would run on any old oil. Have we gone forward or backward in the car industry, when was the last time you adjusted you 200 quid electric door mirror, mine was 2005 when I first sat in the car.

[Smilge]

Me thinks thrust release bearing a little dry. Try leaving it out of gear, stationary and just operate the clutch to see if the noise disappears when it's depressed.

[Seatdriver]

Checked release bearing, no noise nice and quiet.

Funny thing is if you labour the engine ie 2nd gear 10mph floor the throttle and quickly dip clutch as taking foot off gas its a damn sight louder. Now I realise the turbo is spooling up at this time during hard acceleration but this dry bearing sound is reflective of the engine speed not the turbo (which I think will be spinning extremely fast at this point)

Ok question for seatkid or anyone who knows the definate answer to this one.

If the engine is accelerated hard in any gear the turbo will begin to spool up, if you suddenly take your foot of what happens to the turbo vanes (ie I think they open fully) but what happens to the boosted air that is no longer required as there are no dump valves on these type of turbos? Do the vanes just get rattled!

Anyway dealer wants the car back asap to carry out investigation

Will let you know the findings

[Willie Krashitt]

Can't say anything definitive about your noise, but I am able to answer your question about the turbo.
There is no need for a dump valve on a diesel as the engine is unthrottled so the "excess" air simply goes through the engine. The turbine doesn't stallout like in a petrol engine but slows down more gradually.

The vanes will pre-position to a closed position as the engine speed and boost pressure drop. Remember that on the overrun, ie downhill with closed "throttle" - more accurately no pedal input, there is no fuel going into the engine so no energy to spin up the turbine, hence the need to close in readiness for the next boost demand.

Hope this helps,
George.

[Seatdriver]

Big Wheel.

Car returned to Seat main agent. They checked every moving part, re-torqued all bolts, used listening equipment on all rotating parts removed the cam belt cover and with engine running checked for noise, and came to the conclusion yes they could hear the noise but be damned if they could find what was producing it. They then ran an 09 tdi 130 and aparrently it made the same noise but a lot quieter.

My conclusion at the mo is that the turbo is clogging up due to continual short cold runs. My solution is give it a 1 hour blast on the steep country lanes this weekend and change the car for a newer one early next year (2.0 140bhp Alhambra Stylance is getting rather tempting) as this Alhambra it is now getting on a bit.

Out of interest big wheel what is your car driven like ie short runs never warming up and how many miles has your car done.

[Dowdman]

Help my Alhambra got the same problem I have changed gearbox oil and both driveshaft the car had a clutch and flywheel before I had it

[Dowdman]

Help my Alhambra got the same problem I have changed gearbox oil and both driveshaft the car had a clutch and flywheel before I had it

[xavier]

I had similar symptoms to this before I started getting limp mode with my turbo. I'd suggest testing the turbo actuator arm manually and see how stiff it is, if there's much resistance I'd suggest either a chemical clean (relatively short-term fix) or a remove and send it off for a clean fix (relatively longer term fix).

 

Might be an idea to add your car details to either the post or your sig as if you're driving round in a petrol the paragraph above won't be relevant.