Does this sound like worn shocks?

Ben Harris · Post by **Ben Harris** » Thu Apr 01, 2004 5:11 pm

On my way home from work today, whist moving in a straight line amongst traffic that kept alternating between 40mph - 50mph - 40mph - 50mph..... I noticed that every time I put my foot on the accelerator, the car pulls slightly to the right, and then when I take it off again, it pulls to the left. I'm guessing that the front of the car is lifting higher on one side (right?) when accelerating and making it move to the right, and then dropping lower on the same side when engine braking, causing the other side to be higher (left?) and making it go left. Does this sound feasable?

Is this likely to occur if one shock had worn more than the other, or does it sound more like a damaged / worn spring? I've ruled out sticking brake, as this would cause it to pull to the same side on both acceleration, and deceleration.

Oh, and this is on my 480 with standard suspension, not the lowered one!

Ben.

MatBat · Post by **MatBat** » Thu Apr 01, 2004 5:21 pm

Havent bent a wishbone? Strange things happen when you do that

Ben Harris · Post by **Ben Harris** » Thu Apr 01, 2004 5:36 pm

I doubt it's the wishbone. I can't think of any reason it should have become bent.

I've been a bit suspicious about the shocks on it anyway. I've got used to the hard suspension on my other, lowered 480, and I can't tell if this one is too soft (worn shocks), or if I'm just comparing it with the uprated suspension of the other one, and finding it soft in comparison.

I think, in light of today's discovery, it probably is the shocks. I just wanted someone else's opinion that my theory was possible! I've also noticed that the wheel to wheelarch height isn't the same on all the wheels (left-right). I'm not quite sure what's causing this, but if worn shocks could be the cause, then I'll definatly get some new Bilsteins to put on it!

(Just looking for an excuse!)

Ben.

Frantic · Post by **Frantic** » Thu Apr 01, 2004 11:03 pm

Have you checked all your 4 tyre pressures lately?

volvofox · Post by **volvofox** » Thu Apr 01, 2004 11:24 pm

get a tracking done !
wouldn't harm in any case.

how was the 'waterproof'level of the road. was it angled sharply ?
did trucks drive grooves in the road ?

worst case senario and a long shot : differential. check oil of gear box. look at steel content (steel chips) of the bottom plug.

I think your spooked. do as the italians say "piano"

Ben Harris · Post by **Ben Harris** » Thu Apr 01, 2004 11:25 pm

No I haven't. That's something that MatBat also commented to me when I was talking to him earlier, and seems like quite a likely cause. I'll check them tomorrow, and report back!

Thanks for the suggestion!

Ben.

volvofox · Post by **volvofox** » Thu Apr 01, 2004 11:29 pm

Frantic wrote:Have you checked all your 4 tyre pressures lately?

come to think about it : I noticed my car pulled to the right one morning.
"meia culpa" (me to blame) I had only 1 bar in the rh front tyre, which in my case should be something upto 2.0 bar. The whole cheek of the tyre was dammaged, didn't dare to take it 200 km/h to germany anymore and had to replace them fast luckyly they were on my wish list as they were done.

Ben Harris · Post by **Ben Harris** » Thu Apr 01, 2004 11:29 pm

volvofox wrote:how was the 'waterproof'level of the road. was it angled sharply ?

I think the word you're after in English is "camber".... and whilst there was a camber on the road, it wasn't overly steep.

volvofox wrote: did trucks drive grooves in the road ?

Yes. Lots of trucks do tend to go along that road, but not in the lane I was in.

The difference between acceleration and deceleration was quite a distinctive right, then left, and once I'd noticed it, I tried it several times and it did the same each time.

Ben.

volvofox · Post by **volvofox** » Thu Apr 01, 2004 11:55 pm

your steering assy is a bit too sensitive. I think seen from the side of car the "king pin" must lean backwards on the top more. Get it tracked.

the car hops from one truckgroove into the other because the axle's of trucks are wider. , Your car can by matter of speaking not realy decide which groof to take: eiter the left or the right.

no bad idea to check tyres anytime

anyways forgot to tell: nothing to do with shocks. donot let you get fooled by peops wanting to sell shocks. It happens too many times.

thanks for learning me a new translated word : camber.

chris1roll · Post by **chris1roll** » Fri Apr 02, 2004 7:01 pm

worn engine mountings? Try rocking your engine about.
Just an idea

Ben Harris · Post by **Ben Harris** » Sat Apr 03, 2004 10:54 pm

Well, I checked the tyre pressures today, and they were spot on (surprisingly).... so it's not that. Also, it was doing it regardless of which roads I was driving on, so not truck groves either.

I think what's happening, is that it tends to pull to the left ever so slightly, when just driving normally. Both my 480's do this, to the same extent, and I'm sure I've read it in the manual somewhere that the steering is designed to have a slight negative camber. So... what's actually happening, is that the left pull is normal, and it's just the right pull when accelerating hard that's unusual. Driving along in the dark just now, I noticed quite a considerable rise from the headlight beam on the road when accelerating hard, which may indicate worn shocks (as I suspect). Also, the front shocks were considerably softer than the back ones, when I tried bouncing the suspension earlier on today.

I have just had the garage do a cam-belt change, and they didn't comment on anything. I'd like to think they'd have said if the engine mountings were on their way out, but I'll check tomorrow, anyway.
Do they drop or raise the engine to change the cambelt, as I can't see how they could manage to get to it without doing this? Is it possible they've done something that's caused it, as I don't remember noticing it before, but then again, that doesn't mean it wasn't there!

Any more thoughts? If you think getting the tracking checked is a worthwhile thing to do first, then I'll get that done, but as I suspect it's the shocks anyway, I'm a bit reluctant to waste money getting the tracking done first, as it'll only need doing again once I've changed the shocks!

Ben.

Ben Harris · Post by **Ben Harris** » Mon Apr 05, 2004 6:12 pm

UPDATE:

The engine mountings seem fine. I've given the car a look over, and can't see anything obviously wrong. There doesn't seem to be any play in the shock mountings (I suspected the shock top or bottom mounts, but it doesn't look like it's that). No play in the lower wishbone mountings. The brakes aren't binding or staying on, either. The only thing I could find was a small amount of play in the drivers side wheel bearing. It didn't seem to be very much, and wasn't commented on 6-months ago for the MOT, but I don't know if it's enough to cause the symtoms I'm seeing.

I've noticed that what's happening is even if I hold the steering wheel straight - the car always drifts right under acceleration, and always left under deceleration (with the steering wheel still held straight). When driving along steadily, the car stays in a straight line and doesn't wander (rules out worn steering rack as far as I can see).

Thanks for all your help so far, but this is a plea for any more suggestions!

Could the slight play in the drivers side wheel bearing producue these results?

....oh, and I'm 99% ceratin this problem has appear since having the cam-belt done, but I've spoken to the garage that did it, and I agree that they didn't do anything that would obviously have caused this!

Ben.

john hotchkiss · Post by **john hotchkiss** » Mon Apr 05, 2004 6:29 pm

the garage are gonna say that put mine in for a oil&filter change & flush at national gave me a oil leak said it wasnt them wasnt there before i gave them it