Bad handling '95 993 need help

Augustus · 07:16 AM

I've just had my 3rd alaignment done three weeks ago. Figured the first two guys didn't know what they were doing or didn't care to do a thorough job..

After the last alaignment I went for a test ride and the car pulled to the right...while just driving smoothly, went back and explained this to the guy and he said that I have radial tire failure..... OK...

Things get worse. On the drive from PG to SF on HWY 1 yesterday I was driving through a long right hand sweeping turn doing about 65mph, let off and the car went to the right, like I was making a right hand turn..or changing lanes.

On a long clearly visible down hill section and then a climb uphill-overall about a half a mile with no intersections I passed a car (legal pass not the speed though) at 80mph. I ran over a section of roadway that was patched and the car didn't like it, the car got light and when it came back down it went to the right enough to startle me..

So, exit HWY 92 to get on 280 (do eighty) north bound and...while cruising at 70 mph on a straight I hard accellerate and the the car goes to the right, not a little but what seems like two feet.

I have fairly new Monroes with H&R sport springs which lowered the car lower than ROW.

During the last alaignment I had him look at all bushings, he said everything was ok. This guy is not a Porsche guy but he does specialize in alaignments for race cars. That is his core buisness.

Any help is appreciated.

Bill Verburg · Bill Verburg's Garage

Quote:

Originally Posted by Augustus

I've just had my 3rd alaignment done three weeks ago. Figured the first two guys didn't know what they were doing or didn't care to do a through job..

After the last alaignment I went for a test ride and the car pulled to the right...while just driving smoothly, went back and explained this to the guy and he said that I have radial tire failure..... OK...

Things get worse. On the drive from PG to SF on HWY 1 yesterday I was driving through a long right hand sweeping turn doing about 65mph, let off and the car went to the right, like I was making a right hand turn..or changing lanes.

On a long clearly visible down hill section and then a climb uphill-overall about a half a mile with no intersections I passed a car (legal pass not the speed though) at 80mph. I ran over a section of roadway that was patched and the car didn't like it, the car got light and when it came back down it went to the right enough to startle me..

So, exit HWY 92 to get on 280 (do eighty) north bound and...while cruising at 70 mph on a straight I hard accellerate and the the car goes to the right, not a little but what seems like two feet.

I have fairly new Monroes with H&R sport springs which lowered the car lower than ROW.

During the last alaignment I had him look at all bushings, he said everything was ok. This guy is not a Porsche guy but he does specialize in alaignments for race cars. That is his core buisness.

Any help is appreciated.

check the easy things like tire pressure first, if that's ok you need to take it to a shop that has some experience w/ 993s

Augustus · 06-12-2011, 07:24 AM

Thanks Bill.
Tires pressure is correct.
The first two alaignments were done at an experienced 993 shop, that is why I went to another shop for the third alignment. I think I'll get new tires and have some of Chuck's bushings installed.
If that doesn't make the car handle better I'll get some PSS10's or something one grade lower...bilstiens?

Turbo Werks · 06-12-2011, 07:00 PM

The kinematic toe in the rear could be out of adjustment, you need a special tool for that.

Augustus · 07:24 PM

The first shop that did the alignment uses that special tool and he is a highly respected 911 shop. Maybe I should just go back to him and give him...another try at it.

cjoenck · 06-13-2011, 06:56 AM

The obvious questions

- do you know the history of the car?
- has the car ever been in an accident?

I know this seems pedestrian but have someone follow you and take a look at you car from behind. If your car looks like it is "running like a dog", i.e. back wheels offset a little you may have some serious structural damage that no alignment can cure.

Just a thought.....

David in VA · 06-13-2011, 09:39 AM

Very bad wheel bearings can also cause something like what you're describing, could be something to check as well.

Tyson Schmidt · 06-14-2011, 05:16 PM

Have ALL of the rear suspension links checked very thoroughly.

I once found a bad link where the bushing had become unsecured (no longer in a press-fit) from the control arm so that it moved laterally, but if you checked it for slop in the conventional manner it felt fine. It was also a '95.

Also, IIRC the '95 993 had a recall on the rear ball joints or control arms, can't remember specifically now. Have your shop do a check for that.

Augustus · 06-15-2011, 06:01 PM

Thanks for all the ideas guys..I have some pressing matters and I won't get to the car for several weeks.

cgfen · 06-20-2011, 01:23 PM

Quote:

Originally Posted by Augustus

I've just had my 3rd alaignment done three weeks ago. Figured the first two guys didn't know what they were doing or didn't care to do a thorough job..

After the last alaignment I went for a test ride and the car pulled to the right...while just driving smoothly, went back and explained this to the guy and he said that I have radial tire failure..... OK...

swap the front tires L-R and see what happens

70ep · 06-20-2011, 01:56 PM

I agree with Tyson; problem's in the rear suspension.

RSstop · 06-28-2011, 04:45 PM

I found the same thing as Tyson on a 95. 1st check, all bushings appeared ok, but finally found a joint on the rear toe link was worn. Same symptoms as you describe.
Lyn

Augustus · 09-03-2011, 08:04 PM

A big thank you to eveyone who replied..

I replaced the front lower control arm bushings and put on a new set of Sumitomo's...the car now handles very nice!

Traveller · Traveller's Garage

Quote:

Originally Posted by Augustus

I replaced the front lower control arm bushings and put on a new set of Sumitomo's...the car now handles very nice!

Unfortunately, when you make more than one change at a time, you never know for sure which change solved the problem.

Augustus · 09-04-2011, 08:24 AM

I changed the bushings first... car still handled bad.........then I got the tires.

Quote:

Quote de Augustus

I replaced the front lower control arm bushings and put on a new set of Sumitomo's...the car now handles very nice!

Unfortunately, when you make more than one change at a time, you never know for sure which change solved the problem.

lucittm · lucittm's Garage

What brand/size of tire did you replace? How much tread was left? Seems odd that a tire or tires would cause the car to handle poorly enough to be dangerous on the road unless they were extremely under or oversize.

Mark

Augustus · 09-05-2011, 09:22 AM

I replaced the Dunlop stock size tires with Sumitomo stock sized tires.
The reason the new tires solved the handling problem was because my first two alignments were set up for hard cornering. Hence the tires wore out on the inside tread. My third alignment was to stock specs and since the tires were worn out on the inside the car handled badly.

Joe Bob · Joe Bob's Garage

There ya go....unless a ride is a dedicated track car it's adviseable to use stock specs....