Sounds like rumbling from the tensioner on cold start up?

V70RINBLACK · Post by **V70RINBLACK** » 26 Feb 2006, 07:24

Hi, I have to congratulate the forum on the depth and level of informative data.
I'm from the Motor vehicle world all be it (exotica) and find the information you guys have paved invaluable.

The Volvo I have at present (you can probably tell from the screen name) is a 1997/98 'R' reg V70 R. It has been not too bad on reliability in the last three years that we have owned it (97000 miles) annualy doing around 7000.

It has had a faulty ABS Modulator that got changed under warranty and the baro sensor failed. (changed this myself as Volvo stated it was not possible, that particular garage was out to make money rather than help the motorist).

Now just before service time and before the yearly MOT I have acquired a curious rumbling/almost like a loose piece of engine trim rattle, always on cold start up. From warm or moderatly warm no noise. (I know what you are thinking, no its not lifters or ends)

From standing over the engine it sounds like it is comiing from the ancilary belt tensioner. (Thoughts could be if there are rubber components inside shore hardness up when cold, if fluid filled viscosities up when cold or tolerances of parts are tight when cold and expand just enough when warm to prevent noise...... my mind rattles on)

Is this likly? has any one else experienced this with their V70?

Any help in this area would be more than greatfully received.

Post by **pfeener** » 26 Feb 2006, 19:54

Can you give us some more info. I assume this is an early model 98 so it has a hydraulic tensioner? and can I assume the timing belt (but not the tensioner) was changed at around 70K miles?

yeagermeister · Post by **yeagermeister** » 14 Mar 2006, 12:49

I noticed a similar noise coming from what I thought was the right front engine bay. The noise was the worst on cold startup, and was also noticeable on initial take-off (I have a manual). I grabbed the manifold, the engine mounts, and nothing moved when the engine was revved. At a certain idle point, though, the rattle appeared. Looked under the car, and all the way back in the middle of the car, the muffler had come unattached from the mount.

No big deal, thankfully. Just something to look at...

Post by **pfeener** » 14 Mar 2006, 13:18

The car will run just fine for a few minutes without the serpentine belt attached. If it happens evrytime you cold start the car, why don't you remove the belt and start the car. If nothing else it will rule out the serpentine belt and idlers.

Peter00228980 · Post by **Peter00228980** » 03 May 2006, 23:08

I seem to have the same problem on my 98' V70 T5.(107,000 miles) It sort of sounds like a bad power steering pump, a belt slipping, or a bad idler or tensioner pully. The noise is only prevalent from a cold start, begins a few seconds after starting the engine, gets louder with increased RPM's, and seems to disapear shortly after the temp guage needle begins to rise. I removed the serpentine belt and started the engine from cold. The noise was still there. I have since replaced the timing belt, timing belt tensioner pully, idler pully, and water pump. The only piece I did not replace was the hydraulic tensioner as it appeared good with no leaks, good compression, etc. Both pully's had some play in the bearings and made noise when you spin them quickly by hand. The water pump seemed OK. It appeared I had found the problem. I was wrong, the noise is still there. I am extremely frustrated. Could it be the hydraulic tensioner is weak due to age and not putting enough tension on the timing belt causing the belt to slip upon cold start due to cold/stiff pully bearings? The only other thing left under the timing cover is the oil pump. Has anyone with this problem found a solution?

Post by **matthew1** » 03 May 2006, 23:17

It's a mystery:
https://www.matthewsvolvosite.com/chat/p ... =6478#6478