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Hey everyone,

Really hoping some folks can point me in the right direction here. I'll try to include all the details in case things are related. I'm having a really hard time diagnosing things, and not sure my mechanic will be able to.

I bought a 1999 Stag RS Four S turbo manual recently, and the test drive went well, as did mechanic's inspection. Came with loads of receipts for work done. Mechanic came up with worn out Tension Rods. It felt like it needed a wheel alignment (pulling right) but other than that drove well. Tension rods have not yet been replaced.

Here's where I'm at:

The seller recently added big wheels, stretched rubber (ie slightly less wide than very wide wheels), EBC, turbo timer, new coilovers (adjustable), exhaust, BOV, HICAS defeater. Seller told me there was a clutching type LSD in the back. Mentioned that it 'grips' a little when making low speed turns. HICAS light is always on, I assume from the HICAS defeater.

Issue 1 - Driving at around 30-45km/h - feels something like a lumpy progression - like a wheel or two is not round. Feels more from the back ie the whole car is either push-pulling back and forth a bit, or it sometimes feels like it's wobbling side to side a little bit as I move along. It rocks me in my seat at times.

Issue 2 - Steering feels loose - like it wanders at times, and other times just feels a bit floaty. Sometimes it feels like the back end is floaty, other times it feels like the front end. But I can keep it in a straight line holding on to the wheel, and can turn and change lanes somewhat predictably/can adjust as things move around a bit. Turning one side to the other doesn't really feel like there's a deadspot in the middle. Seller had replaced right front tie rod end. My mechanic diagnosed a new tie rod end needed for the left front, which has been done now.

Issue 2b - Occasionally, when driving slowly, around 20-40km/h, I get a pretty chunky metallic clunk/click from the front (it seems). Really feels bad, like there's something massive that's loose. But steering functions the same way.

Issue 3 - Also feeling a really strong wobble at a higher speed - this is the most familiar, with other cars I have owned. Feels like a wheel balance and wheel alignment issue. Violent shaking at times felt through the steering wheel.

Issue 4 - When driving up a hill especially, if I give it a lot of accelerator in 2nd or 3rd, around 2100-2800rpm, when doing 40 or 60km/h, the whole car has a full on vibration/shudder to it as it puts down the torque, and this eases as the RPMs of the engine go up and faster speed in achieved.

Issue 5 - Just recently, every now and then the Check Engine light comes on for a few seconds, then goes off.

Mechanic inspected all driveline recently and said it was a-ok. Not sure how true this is at all.

Any thoughts on the above? Here is my list of things under consideration:

- Tire issue/something triggering an issue with ATTESSA-ETS (all tires are the same side) - tires are 245/45R17's stretched onto wheels that are 'Silver SC Style Mustang Wheel - I think 17x10 at the rear, not sure if they're 10 or 9" on the front.
- Engine mounts
- Gearbox mounts
- LSD/driveshaft issue
- Wheel alignment
- CVs
- Front prop shaft
- Universal joint
- Tension rods

I don't think it has had a proper alignment since the outer toe ends were replaced at the front - this could be a part of what I've been experiencing. There's a mysterious comment on a mechanic's invoice about 'RE & RE both front CV Shafts. Replace inner boots." It's 3 hrs of labour. Not sure what 'RE' stands for in this case. But do have receipts for CV boots from Febest Parts.

Any thoughts much appreciated!! Worth noting I'm an Aussie living in Canada.. so I'm lucky to have a decent mechanic here but Stagea's are pretty much never seen on the road.

Thanks so much,
Luke

Edited by ls_stag

Could be play in all the suspension components, anything that allows the wheel to wobble freely outside of its intended geometry. The front inner and outer ball joints also would be a candidate for replacement at this age. They make a dull constant knocking and rattling when going over bumpy road.

The steering rack bush may help the steering feel too, but the rest of the suspension needs to be done first.

Ball joints and adjustable caster arms are easy in terms of labour, they are bolt in items. Just hope you don't have to do too many bushings. Ive done them myself but they cost a lot in terms of labour if a mechanic has to do them.

 

1 hour ago, zoomzoom said:

Could be play in all the suspension components, anything that allows the wheel to wobble freely outside of its intended geometry. The front inner and outer ball joints also would be a candidate for replacement at this age. They make a dull constant knocking and rattling when going over bumpy road.

The steering rack bush may help the steering feel too, but the rest of the suspension needs to be done first.

Ball joints and adjustable caster arms are easy in terms of labour, they are bolt in items. Just hope you don't have to do too many bushings. Ive done them myself but they cost a lot in terms of labour if a mechanic has to do them.

 

Thanks zoomzoom - I'll ask my mechanic to do a careful inspection of all those items. Any ideas on how the cause of a problem is usually identified? Is it a random sort of replace one piece at a time and see if that helps situation? My guess is that there is a specific part that's got a problem, and is making the occasional metal 'clunk' noise/impact that I feel in the floor from time to time (not constant and not associated with bumpy roads specifically).

 

 

6 hours ago, ls_stag said:

Thanks zoomzoom - I'll ask my mechanic to do a careful inspection of all those items. Any ideas on how the cause of a problem is usually identified? Is it a random sort of replace one piece at a time and see if that helps situation? My guess is that there is a specific part that's got a problem, and is making the occasional metal 'clunk' noise/impact that I feel in the floor from time to time (not constant and not associated with bumpy roads specifically).

 

 

Suspension issues generally involves sticking a prybar wherever you can and trying to move the various joints. If you can feel even a tiny amount of movement by hand, the forces that the car can exert in motion sure will move them.

Having said that, ball joints don't cost too much (except if you buy them from Nissan). Ive had ebay aftermarket ones on my vehicle for a good 4 years now and along with tie rods and bushings I really sharpened up the steering feel and stability, where before the car would get pulled side to side by the road surface.

It can be hard to say that a single item is the cause. As all the components wear and develop their own play, the total amount of play in the wheel will increase.

Another thing worth trying is polyurethane subframe collars (note collars, not bushes). The standard rear subframe bushes have movement in them for road compliance but they get sloppy with age. poly subframe collars reduce the movement of the subframe and hopefully extend the remaining life of the stock bushes. I wouldn't even suggest replacing the full subframe bushes, unless you were doing a full ground up build.

12 hours ago, zoomzoom said:

Suspension issues generally involves sticking a prybar wherever you can and trying to move the various joints. If you can feel even a tiny amount of movement by hand, the forces that the car can exert in motion sure will move them.

Having said that, ball joints don't cost too much (except if you buy them from Nissan). Ive had ebay aftermarket ones on my vehicle for a good 4 years now and along with tie rods and bushings I really sharpened up the steering feel and stability, where before the car would get pulled side to side by the road surface.

It can be hard to say that a single item is the cause. As all the components wear and develop their own play, the total amount of play in the wheel will increase.

Another thing worth trying is polyurethane subframe collars (note collars, not bushes). The standard rear subframe bushes have movement in them for road compliance but they get sloppy with age. poly subframe collars reduce the movement of the subframe and hopefully extend the remaining life of the stock bushes. I wouldn't even suggest replacing the full subframe bushes, unless you were doing a full ground up build.

Thanks zoomzoom - any idea who sells the subframe collars? That sounds like a smart upgrade.

Do you have a reliable ebay source for ball joints and bushings (any specific name for the bushings you replaced)?

Thanks again!

Quick follow up - the mechanic thinks it is the tension rod bushings/bushes. Also, tires were out of round, so they put the worst ones on the back. Also, had a 4 wheel alignment and the toe was f&%ked at the front. Also got the wheels balanced. So the bushes are going to be replaced with Whiteline KCA332's. Car is driving a bit better already after the alignment. Considered replacing with adjustable rods but aiming to keep budget for some other items at this stage and after reading up, I don't really see the advantage in having more adjustability.

 

Edited by ls_stag

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