1999 V70R Knock under car

victor vector · Post by **victor vector** » 22 Nov 2016, 19:42

1999 V70R 160k miles has developed an anonymous knock from what sounds like under the car and to the front passenger side. It doesn't seem to be affected by light load and is intermitent when driving along jerking the steering left/right. It will stop clunking when over 40/50 MPH. It is not an obvious dangling or loose part. I replaced the struts 3000 miles back and the knock didn't start until a 1000 miles ago, so I can't say one caused the other. Can detect tiny amount of play in 1/2 shaft that side. Drive shaft to back axle has small noise but different frequency so I don't think that's it. Any one know this noise ??

Also......this car smells a lot of engine oil at start up with no obvious leaks. I think it's most lightly the PCV valve and related kit. I'm wondering if the PCV valve has any effect on the throttle response, it being intermittent and prone to surging. And would the PCV affect the transmission which had got a bit jerky too even after having the tranny fluid changed ??

Many questions on this car. I love it but am becoming disillusioned by the number of electrical codes crashing all at once and the cryptic diagnostics available to us handy laymen. My XC70 2000 has just died completely too. It literally fizzed out and will not start. Codes say camshaft sensor not reading so it's prolly a timing belt m' tinks.......long cold winter is acomin'....

Post by **abscate** » 22 Nov 2016, 20:43

IS the axle play axial (along the direction of the axle shaft) or radial (play in the CV joint)? You should not feel any play in the radial direction

Post by **850 LPT** » 23 Nov 2016, 05:34

Good idea to check the CV axles, but I am also wondering if the AWD drive shaft can make clunking noises when the carrier bearing is failing?

On your XC: A bad camshaft positioning sensor will indeed leave you with a no start situation. These are very easy to replace.

victor vector · Post by **victor vector** » 24 Nov 2016, 13:01

On drive shaft, there is s tiny amount of rotational slack and 3/8' longitudinal. Is that sign of knackeredness ??

Is there any correct impedance numbers for the sensor ??

Thanks for the clues chaps.

Post by **scot850** » 24 Nov 2016, 13:46

As I am looking for a variety of knocks, clunks, groans under my car I wish I could help on those, but having replaced most of the suspension, bushes, end-links, anti-sway bar at both ends it drives me nuts!

On the starting issue/jerky transmission, it could be the ETM playing up. My ETM used to be difficult to control the smoothness of the throttle application, even after the Xemodex repair. The dealer accidently did a free upgrade to my ETM which I think also affected the transmission changes as they are definitely not as rough as they were. I do have the 5 speed auto not the 4 speed you have, but it was an ETM software change as I understand.

Have you checked the fuel pressure at the fuel rail? Look for 43+ psi.

Check connections of the crank sensor, cam sensor and temp sensor to make sure they are all in good condition and corrosion free. Also check the B+ cable in the connection and below the connection in the main kidney shaped fuse box for melting issues.

On the clonks, check the sway bar end-links, they groan and then start to clunk as they fail, check the bushes on the front ant-sway bar, sheck the engine mounts, particularly the one under the crank pulley, and the top torque mount.

Neil.

victor vector · Post by **victor vector** » 07 Dec 2016, 17:39

Prolly found the source of the klunk.... what say you ??

The pictures show what fell off in my hand and where it was.

Post by **scot850** » 08 Dec 2016, 09:33

Yup, that will cause a clunk! Buy a good quality part as a lot of the aftermarket ones fail quickly.

Neil.

victor vector · Post by **victor vector** » 19 Dec 2016, 16:05

Waal, changed out with a cheap and nasty. Still have klunk, so I'll have to gouge the other mounts I suppose, dammit !!

And what's the secret for disconnecting the plug from the boost pressure sensor P0236/7/1600 item. Seems as if a good squeeze should release but it ain't.......Any clues out there ??

Post by **abscate** » 19 Dec 2016, 17:41

Squeeze the wire bail and pull straight off