WH Caprice 5.7L V8 - vibration when idling in Drive and reverse

[Promotec]

All these comments do really help in narrowing down the problem, im about a month from having the available funds to get a mechanic on the job to rectify the probs im having,
but do like having an understanding of whats going on, I do have mechanical skills as trained as a mechanic when I left school but thats many years ago, its always important to know your limitations
though as with modern cars you can create more expence and headaches through stuffing up a job then having to get a mechanic to remedy the problem.

 

[kerryln]

Unfortunately I still have the problem but haven't checked the fuel line or the centre bearing as suggested earlier. However, I am now getting some warning lights coming on intermittently. Usually the engine light, ABS, Trac & airbag lights come on together with an audible signal and occasionally the oil light for good measure. When these come on the power steering becomes quite a bit stiffer as well.

Looks to me like a module is buggered somewhere. I'm having this checked out in the next few days. Maybe that will solve the idling problem as well, I can only hope.

I had the ABS module replaced yesterday and the issue with the warning lights & power steering has gone away, as expected.

The vacuum lines and fuel lines have all been checked and cleared as OK.

Unfortunately the vibration is still there. I think I'll learn to live with it.

Thanks for everyone's feedback and help.

Kerry

 

[bricat]

I had a similar vibration turned out to be power steering pump. Worth a look. Was really loud banging though.

 

[umair]

Get under the car by parking on a ramp or something high. Make sure you pull your handbrake and in park. The driveshaft has two metal poles connected by a center bearing. Grab each pole by your hand and rotate each pole in the opposite direction of the other pole. It is like when you wash your clothes and want to take the water out, you twist the cloth with your hands. Each hand moves in the opposite direction. Same idea. You want to twist the poles. If they twist then the center bearing needs replacement.

 

[Promotec]

well
kerryln, my vibration problem sounded similar to yours, vibration through the body in reverse, worse backing up a slope
then if put in park after reversing vibration remains, a few times slow forward on unevn ground.
Finally got it sorted and fixed, engine mounts, they were stuffed, had them replaced today, its made a huge difference
no more vibrations in reverse or anywhere else, running alot smoother, and noticably quieter to start. Feels good
however $520 to have it done by lubemobile hurt the wallet, but the convenience of having it done at home at a specified time etc etc etc
justified the cost.
Certainly hope you get your car sorted out soon, the result justifies the effort/cost
Regards Chris

 

[david dubbo]

also check o2 sensors as mine was doing similar thing and replaced the sensors and it idles heaps better

 

[kerryln]

Engine Mounts.

well
kerryln, my vibration problem sounded similar to yours, vibration through the body in reverse, worse backing up a slope
then if put in park after reversing vibration remains, a few times slow forward on unevn ground.
Finally got it sorted and fixed, engine mounts, they were stuffed, had them replaced today, its made a huge difference
no more vibrations in reverse or anywhere else, running alot smoother, and noticably quieter to start. Feels good
however $520 to have it done by lubemobile hurt the wallet, but the convenience of having it done at home at a specified time etc etc etc
justified the cost.
Certainly hope you get your car sorted out soon, the result justifies the effort/cost
Regards Chris

Thanks Chris. I've replaced the engine mounts and it actually made the problem worse. Before they were replaced the vibration was only noticeable in reverse. After their replacement, it was noticeable both reverse and drive. I wonder if I should suspect the new engine mounts but that seems highly unlikely.

My mechanic said that he loosened the mounts and jacked the engine up a few millimetres and the vibration stopped. Why has got me stumped.

Kerry

 

[kerryln]

also check o2 sensors as mine was doing similar thing and replaced the sensors and it idles heaps better

If it was the o2 sensors I would assume it would affect things in neutral as well as reverse and drive. Would that be correct?

 

[SavVYute]

Exhaust flange joint loosening where it comes off the manifold.

 

[kerryln]

Exhaust flange joint loosening where it comes off the manifold.

There's a thought. This problem has to be caused by something"unusual" that's not readily obvious and that's just the sort of thing.

Thanks, I'll check it out.