BOUNCING CAR, Whats Happening to my 6G? Options

[6gBubbs]

Hi All,

Any help on this matter is greatly appreciated.

Recently, when I pull off from a stand still my car has started bouncing on the front end. It's quite a hard bounce that knocks and bangs and rattles everything in the car.

I have no idea what is causing this but a friend and I done the usual bounce the car by pushing the wings test and everything appears to be evenly matched left to right.

Does anyone have any ideas as to what the cause could be?

If needs be I will try to get a video of it happening but it will be from inside the car with my iPhone mounted on the screen mount.

Many thanks in advance

Rob

[Nihil]

I'm not an expert here, but if the car is bouncing, I'd guess you got a problem with your shock absorbers

This post has been edited by Nihil: Aug 17, 2012 - 8:23 AM

[rave2n]

Struts are blow.

Go push the vehicle down hard, and if it bounces up and down, instead of just down and steady back to stance. Dead strut.

Unless you are running some ebay coilovers, its most likely strut.

[Syaoran]

If you did the push test and everything is good, then maybe you have busted engine mounts. It sounds like you're having wheel hop.

[6gBubbs]

The car is bog standard with the exception to HID upgrade, cone filter induction kit, head-unit and upgraded standard mount speakers. No cheep-crappy eBay coil-overs here.

I have done the bounce test for the shocks but that came back as normal. So it looks like it may be engine mount(s) creating wheel hop. How can I check the engine mounts to see which ones are gone (if not all of them) and does anyone know what they are likely to cost and the best place to get them from?
Does anyone know if there are polyeurethane engine mounts for the 6G Celica 1.8 AT200 similar to those that powerflex do and if so is it worth the upgrade (pros and cons of the upgrade if possible)

Many thanks.

Rob

[rave2n]

My ST did this a while back, was the clutch.

Sry for the first post, didn't read it all the way, or realize what you ment by "bouncing"

basically the clutch was slipping off the flywheel causing some pretty hard vibrations. I assume it coasts normal?

Can exclude that quickly by checking your slave, and if off, bleed the line.

This post has been edited by rave2n: Aug 19, 2012 - 4:07 PM

[6gBubbs]

It drives normally and coasts smoothly.

I don't get any clutch slipping when I pull off so I'd tend to look away from a clutch fault especially as if I rev up and dump the clutch it is fine, it picks it's wheels up, smokes the street out (whoops) and takes off like a scalded cat with a rocket up its ar*e and it doesn't bounce around.

It only does it when I go to pull off normally. This is what is so weird about it. If it was because of a racing start then I'd know that it's tyre shake but to do it under normal (SANE) driving conditions is really odd.

Anyway I have been trawling round the motor factors in Sussex and no where can get them, everyone is saying "gonna be Toyota direct for that mate" so off I pop down the local Toyota Showroom, and get given a price of between £60 and £215+VAT depending which one is gone or the whole lot is nigh on £600 inc VAT. So if anyone knows of anywhere in the UK where I can get mounts from that aren't a main dealer it would be greatly appreciated.

I also noticed earlier that I have a slight camber imbalance going on (although this may be to do with the surface it was parked on) - (the vertical alignment of one wheel is near enough vertical and the other leans in towards the top of the wheel. It's not huge but could that be the cause of it.

Many thanks in advance again

Rob

[yellowchinaman]

ok. If the car is bouncing it's the shocks. But now your referring to the engine bouncing? Which one is it? Engien moving a lot is easy. Just rev it highand let it drop. If it rocks and knocks about then its the mounts.
If cornering and taking off means the car slings like a boat and bounces then its the shocks.

[6gBubbs]

The car is bouncing on the front end and I would say it is pretty much what Syaoran has described as being "Wheel Hop".

The reason I said about the engine is because rave2n said about his clutch slipping off the flywheel.

yellowchinaman: with respect of your comment about "cornering and taking off means the car slings like a boat and bounces then its the shocks" it doesn't sling about like a boat.

I will try to get an onboard video today of it doing what it does so that people can hopefully help me with this.

Rob

[rave2n]

Yea that video may help, cause I'm still confused on what the problem may be...

[Smiles98]

If its the mounts than all you do to check is rev the engine if you hear the knock then its the mounts.
Its easier to have someone else rev the engine while you <with the hood open> watch the mounts and listen to the engine.
... bounce test if you get the car going how many bounces are "Normal" i go with 2 tops
have you changed the tires recently? Proformance tires add more grip which may cause the car to "bounce" at take-off.

[richee3]

Are these hard or soft launches when the car is bouncing?

[6gBubbs]

The bounces are very aggressive. It only does it under normal launches. The car has reasonably new Bridgestone Turanza tyres all round on it.

Another one of my friends has had a look at the car today and he thinks that the issue is the rear left strut causing the car to "squat" one way meaning the front right wheel is not sat with the full car weight on it meaning it is slipping and causing the bounce. He jacked the car up and there is signs of excessive wear on the strut and the spring needs replacing too as it isn't coiling properly.

I don't see the point in spunking £300 on a set of standard rear struts and springs. I'm looking at dropping the car down soon anyway but I want to know what lowering strut and spring options I have on my car. I've looked on FenSport and there doesn't seem a lot for the 1.8 AT200. There is a lot for the ST202 and ST205 but are these compatible with my car at all or do I need a specific kit? Any guidance to what kit is much appreciated and a UK Based sales centre would be preferred as if I buy for USA or Japan etc. I will have to pay an "import tax".

[6gBubbs]

Well, since I have been trying to get a video of it it refuses to do it now.

So I'm gonna live with it for now... the MOT is due soon so I will wait and see if they say anything on the MOT and if they do I will deal with it then if not I will live with it until I decide to drop the ride height and sort out a few other things.

[xrav22]

Well, since I have been trying to get a video of it it refuses to do it now.

So I'm gonna live with it for now... the MOT is due soon so I will wait and see if they say anything on the MOT and if they do I will deal with it then if not I will live with it until I decide to drop the ride height and sort out a few other things.

Mine use to rattle in first gear when I take off. Since I replaced the clutch works perfect. It used to happen when its very hot out or I used the clutch alot.
How many miles on the clutch, is it time? I bought a new flywheel also that is probably the cause.

[TannerEsser]

Hi All,

Any help on this matter is greatly appreciated.

Recently, when I pull off from a stand still my car has started bouncing on the front end. It's quite a hard bounce that knocks and bangs and rattles everything in the car.

I have no idea what is causing this but a friend and I done the usual bounce the car by pushing the wings test and everything appears to be evenly matched left to right.

Does anyone have any ideas as to what the cause could be?

If needs be I will try to get a video of it happening but it will be from inside the car with my iPhone mounted on the screen mount.

Many thanks in advance

Rob

i have the same thing. is called clutch chatter it can happen when your clutch is getting worn. or that kind of bouncing can be caused by loose or broken motor mounts.