very strange noise saxo vtr

[johny105]

Ok i'll give you the history as this has me completly baffled.

2002 saxo vtr(1600 8v)
When driving at operating temperature and mostly in 4th + 5th from 35mph upwards sometimes lower gears and speeds but mostly 35mph++. There is a very strange noise hard to describe but i'll try . Its like a loud hum that you can feel on the floor and through the steering wheel it as though something is rubbing on something hollow but its incredably loud. It seams to do it mostly when coming off the throttle and whilst off the throttle(still in gear).

What i've tried so far.

i've had the car on the jack had all the wheels off checked all the driveshafts, balljoints, engine mountings, exhaust etc <all seems to be fine

i work as a bus mechanic and have had some of the other lads in with me and no one has any idea as to what it could be . The conclusion we came up with is that it must be something in the gearbox making the noise.

So i sourced a gearbox and fitted it ,. Took it for a long road test today and the noise is still there(F**KED OFF big time).

Its hard to describe the noise so i'll try and get an audio recording tommorrow.

Any suggestions welcomed


johny

[Defcon5]

Exhaust vibrating against something?

[johny105]

checked all the way along .
with it sounding hollow thats initially what i thought .

[OctyVrs]

Vibration on the overrun. A driveshaft out of balance? CV joint?

Can it be provoked with steering?

[oakdale]

Does it sound like a fog horn in the distance?
If so, I'd be almost 100% certain that it's caused by an outer cv joint.

The outer cv's on these are an unusual design with a tripod trunnion assembly, not the usual six steel balls and make this noise and vibration when the lubrication has dried up or leaked out.

Often, just repacking the joint will cure this, but you should really use a special thin oily grease only available from Citroen.

You could just repack with ordinary cv grease and add a little gear oil to thin it (I've done this several times with total success).

[johny105]

oakdale said:

Does it sound like a fog horn in the distance?

EXACTLY THIS
outer cv joint you say ,
before i got the car on looking over it i noticed the os cv boot had popped off i negotiated my discount and put it back on with new grease when i got the car home.

i'll investigate this asap

johny

[toger13]

another random thing to check the engine mount under the ecu has an m8 bolt in that brakes you have to remove the mount to check as you cant see it this makes the engine drop ever so slightly and can give random noises etc

Si

[edcer26]

My car is making a terrible noise the best way to describe it is it sounds like a seal. It happens when i come off the throttle and also somethings when i put my foot on the clutch. The clutch is new and i have rebuilt the gearbox that is in it but it only really happens when its has a bit on temp in it. The car is a saxo vtr. Any idea what it would be?

[m8rky]

toger13 said:

another random thing to check the engine mount under the ecu has an m8 bolt in that brakes you have to remove the mount to check as you cant see it this makes the engine drop ever so slightly and can give random noises etc

Si

Had similar noises twice,once on a mk2 golf where a gearbox mounting bolt had been refitted wrongly and was intermitently touching a chassis leg.The other on a C2 VTS where the lower engine mount had worn allowing its body to touch on a reinforcing bar under the car.

[johny105]

It was the outer CV boot on mine
When I had popped it back on it didn't occur to me that all the grease had gone
This caused the problem
Popped it off refilled it with grease
All was ok again