1999 Volvo V40 vibration at high speeds

My neighbor's daughter drives an automatic 1999 Volvo V70. 5cyl turbo AWD.

Darn it. I typed in V40 instead of V70 in the title. It's a V70. Anyhoo:

She's reporting severe vibration and power loss at highway speeds going uphill (60-70mph). I took it for a spin and could not get it to duplicate.

The car's check engine light is on for a P0014 (cam position sensor advanced) but have had no work done on the engine in that area. The internet research I've found said that's a common fault for the cam position sensor going bad, and the owners say that engine light has been on forever so I'm hesitant to call that the culprit.

The car has recently had an axle change, so I advised them to go back there and tell their mechanic the problem to which he replied "that sounds like a transmission. I'd ignore it as it's $4000 to fix".

I'm thinking we can do it for way less effort and expense than that. Does anyone have any suggestions or input?

Thanks

On zx2's, the cam position sensor code would show up. It often was that cam timing was off. Exhaust cam had VCT where the sensor was. The vibration could come from many things, engine mounts, exhaust etc.

If the cam sensor goes out, it generally just won't start. I presume it has the coil on plug ignition- If so, it likely has a coil going soft. The first place you notice weak spark is part throttle, converter locked, higher load like climbing a hill...

Should set a misfire code if you can convince it to run badly long enough. If it won't, unbolt the coils, run the engine, and lift each coil in turn- as you lift each one, pay attention to how high you can lift it before the spark cuts out. One will probably cut out sooner than the others. Don't lift it high enough to cut out for any longer than you need to hear it cut. Making it work hard is ok- making it arc internally is bad.

Tires balanced? Bent wheel?

Failing coil? Vibrations won't result in power loss.

I had an 850 that was fwd but on this body, the awd is known for bad "transfer case."
I put that in quotes because it is called something else.

I don't know if this should result in vibration and power loss but sounds probable.

The good news is you can remove the rear drive shaft and the car will continue as fwd with no detrimental effects.

JohnRW1621 wrote: I had an 850 that was fwd but on this body, the awd is known for bad "transfer case." I put that in quotes because it is called something else. I don't know if this should result in vibration and power loss but sounds probable. The good news is you can remove the rear drive shaft and the car will continue as fwd with no detrimental effects.

REALLY? That'd eliminate a few things as far as the vibration goes.

I'll try the coil trick and anything else I can think of. I also plan to take it for another drive as I'd really like to feel this "vibration" for myself.

Thanks everyone. I'll update as I figure out more.

Here is some video instruction that I found.
https://www.youtube.com/watch?v=ISasY0704Mc

In 1999 Volvo offered AWD in sedan and wagon. They also offered a lifted and cladded wagon known as the XC70.
In your research you will likely see XC70 referenced mostly.
The awd system is the same on sedan, wagon or XC70.

The other name for transfer case may be "angle gear."

And angle gears go like popcorn at the movies.

Most likely has to do with cam timing/variable valve timing. Could be the sensor, solenoid, cambelt mis-timed, or even oil pickup/pump problem. The o-rings on the oil pickup leak and suck in air. The variable cam timing is operated via oil pressure, so aeration is a problem.

Ok, sorry for the delay but I FINALLY got another chance to test drive it and this time we got it to shake.

I'm calling this "Definitely drivetrain related". The shake happens around 60-70 primarily when we're on the gas. Letting off the gas makes the shaking go away. Downshifting has no effect on the vibration. No feedback in the steering wheel. Shaking feels like it's coming from the right rear-ish. As I've learned the driveshaft runs down the passenger side on this so it could be that as well.

I noticed no loss in power.

I would call this "driveshaft out of balance" if the vibrations would just stay all the time. The part where it "goes away when you let off the gas" has me scratching my head.

I crawled underneath the car and tried to twist the rear axles to check for play. None noted.

I have the driveshaft removal planned for next weekend. With it removed we'll see if the shaking goes away. If it does I'll have them take it to a balance shop. We'll reinstall another weekend and see what happens.

Good times! If anyone can think of anything else we should try, I'd love to hear your thoughts/advice.

See the video I posted. What your looking for is what looks like a bad CV joint and boot at the end of the drive shaft, (not the end of the axles.)

Once removed you have two options.
1) keep shaft off and run fwd.
2) replace shaft with new or rebuilt

Are they running mismatched tires?
This awd system is very sensitive that all the tires need to be same overall diameter.
Different brands may be quite a bit different in overall size even if the stated size on the sidewall is the same. It's best if they are all the same brand.

Did not check the tires (should have, it was on my to do list). I watched the video, seems pretty straightforward. I'll give the CV joints on the DS an extra gander while I'm in there

Thanks!

Got a text today. Vibration now at 45+mph, more prevalent, and gets worse with sharp right turns.

Originally I butt diagnosed this as coming from the right rear. with the "worse with right turns" can I still say "that may STILL be a right rear issue because that may be the drive axle" or should I be looking very strongly at the left axles now?

Driveshaft removed. No vibrations on our small test drive. Full op check tomorrow.

Oddly though, I didn't see ANY play (aside from a really small "click" from the front and rear flex joints) in any of the components. The driveshaft did have junkyard writing on it though, that may be a sign...

Car driven all day. Vibrations are gone.

Now that we've got to the point that we're no longer worried about the quoted $4000 transmission replacement I'm going to leave it up to them to decide where to go from here. I think they're going to take the driveshaft and car to a driveline shop and see what they find.

Thanks everyone!

Vibration is back.

Driveshaft is removed and the vibration went away for about 2-weeks. Got a text a day or so ago and now the car is shaking again. Same symptoms as before.

The question becomes: Have I removed the rear axles from the equation or could they still be causing the issues?

Thanks!