kkrofft

I am putting our '99 Tiburon back on the road after purchasing it with a broken transmission. When I got the car it had a cracked transmission case and the
left control arm was bent. After replacing the engine and transmission I replaced the control arm and both wheel bearings. I also replaced the front struts and one ball joint and put on a new set of Goodyears.

Here is the problem, If I accelerate slowly and smoothly it behaves normally but if I let up on the throttle while cruising, the wheels turn right a few degrees and the steering wheel turns left a few. If I get back on the throttle the shift reverses. It is drivable but feels extremely unsafe.
Occasionally when cornering it will do the same thing.

My thinking was that since the wheels and steering wheel turn in opposite directions that there must be a problem with the rack or it's mounting but there is now excess play in the steering wheel and the rack is tightly mounted. The tie rods are in good shape also.

I inspected the cv axles as best I could by grabbing the shafts and rotating them to check for slop but found them reasonably tight.

Any suggestions or personal experience is very welcome at this point. I don't want to spend hundreds replacing all the motor mounts or the axles unless I am reasonable sure that it will fix it.

Thanks,

KKrofft

mwood

sounds like an alignment issue, start there first

Stocker

If it were alignment, the wheels & steering wheel would turn the same way.

dddude55

Check that the control arms are tightened. I had the bolt at the front of the control arm come loose, like I could move it with my finger. That would cause the wheel to shift at 60mph on the high way and change where my car was going, was very scary.

kkrofft

Great suggestions. But... Control arms are tight and I had it aligned when I bought the new tires which was right after I installed the struts.

KK

likeyoumeanit

just because you had an alignment done does not mean that it was done right

SR Tech

Motor mounts.... did you replace them when you replaced the motor?

You maybe be feeling engine torque, which if the mounts are so far gone will affect the handling aswell. You normally only feel it when you snap the throttle (open or closed)

likeyoumeanit

^ hey has a good suggestion, whatever busted the trans and control arm may have messed up the mounts as well

kkrofft

True. But I watched them do it and was satisfied that it was correct.




I am leaning towards the mounts as the culprit since I have addressed everything else. I just hate to spend the money on them if that turns out not to be the issue. They all see a little soft but not excessive. Of course I never knew what new ones were like.

I am tempted to tack weld a small bit of steel across the driver side trans mount as it is the loosest. If welding it solved the problem then I would feel much better about replacing it properly.

KK




Agreed. The cause of the trans and control arm failure was the stupid kid who had the car before me revving it up and dumping the clutch.
And slamming into parking blocks while delivering pizzas. I looked it over well before I bought it and have since done a thorough measure up
to be sure nothing else is damaged. I was lucky to find a 1.8L engine and trans combo with only 82K on it for less than $350.
The car runs great and gets good gas mileage. It tracks very well too until I accelerate or decelerate.

KK

Stocker

Having all 4 mounts welded solid will do nothing bad, especially if it's only temporary, unless you count more noise/vibration/harshness as "bad"

Tack a bracket on the mounts, if you feel like it, to see if it helps.

A good test for bad mounts: when you are looking at the engine while it is running and hit the throttle body pulley to rev the engine quickly, if the engine *jumps* back & forth, the front and rear roll stops (the mounts on the bottom) are likely shot. If they are all broken-y looking, you might be able to salvage them by leaving the rubber bits in place and filling them with Windo-Weld or (like me) silicone rubber. Let it cure and it'll be much harder for the engine to roll. You get a bit more NVH but it's not that bad (to me).