Car Jumps Across Road When Going Over Small Bumps

[jason7579 5]

Just wondered if you have any ideas on what may cause it?

 

My car jumps across the road when going over small bumps / ridges in the road. It doesn't veer left or right when accelerating / slowing down. It also sounds like its knocking a bit when going over bumps, but that may be the loose exhaust pipe.

 

What would be the most likely problem?

 

Thanks

[pug_ham 243 3 Cars]

Check your rear beam isn't seized solid or your car is so low its sat on the bumpstops.

 

A few people have posted very similar symptoms when their beam was only of scrap value.

 

Jack the back of the car up & see if one or both of your wheels drop or easier, open the boot & bounce on the sill to see if the radius arms move smoothly.

 

If not then a refurbished beam is needed.

 

Graham.

[jason7579 5]

Thanks.

 

Car doesn't look low, I can just get my hand inbetween wheel and arch.

 

I have bounced the rear of the car and there is no noise and a fair bit of movement.

 

I will jack the back up tomorrow to see if the wheels drop.

 

I did a quick search but all the posts I read had people changing lanes when accelerating or slowing down and my car isn't doing that.

Edited July 12, 2009 by jason7579

[Paul_13 212 1 Cars]

Drop links maybe?

I had this problem, changed them and it stopped to an extent, but turns out the tracking was out slightly.

 

My Dturbo does this awfully, think it could be the track rod ends are knackered

[pug_ham 243 3 Cars]

The knocking could be the droplinks but I'd be surprised if they caused the swerving around.

 

If its not the seized rear beam could be the hub balljoints holes are ovalled & the bumps are bouncing them around causing it to veer around the road.

 

Best get underneath it & have a look/ feel/ pry around to see what play you find.

 

Graham.

[jason7579 5]

My Mums got a car lift at her work, I'll see if I can get it up on that one evening and have a proper look.

 

Thanks

[paul205mi16 4]

Check if Hubs have an ovaled ball joint hole.

[philfingers 5]

you haven't said but is it lowered at all? if so dramatically?

[jason7579 5]

Pretty sure its standard height. I still haven't managed to get under it, hopefully I'll get a chance this weekend.

 

These are the best 2 pictures that show roughly how high it is...

 

http://i10.photobucket.com/albums/a128/jas...05/Image191.jpg

 

http://i10.photobucket.com/albums/a128/jas...05/Image192.jpg

[philfingers 5]

i was thinking along the lines of bump steer due to over low setup and the rack being the incorrect height for the rider height. Rack height is fixed of course but if the ride height is too low it wouldn't be right. As it is the car looks ok. . . . .so you need to egt grubby i think. Mine does the same thing to a degree, it's on PTS tarmac coilovers and is at the lower end of ride height