2009 Pontiac G8 - Holden Commodore Suspension

[Loren]

Looking for some information regarding front end pull on my car. Driving down the road straight, the car goes straight and works fine. Take a corner at normal speed, the car will start pulling to that side after the turn for a while - about a mile or 2 driving straight. Take a turn fast and the pull will last longer. It doesn't go straight down the road again for a while. Could be up to 5 miles before it starts going straight again. Doesn't matter if I turn right or turn left. Car pulls in that direction for a number of miles. It will eventually straighten out. Have had the dealer look at it, an independent auto shop look at it. Noone seems able to figure it out. This was a demonstration car in the U.S. which was run on a track for about 15K miles before I bought the car. One possible explananation is they altered the programming on the ECM module for the Body / Chassis Control Module. Has anyone else ever had this type of behavior on their car? Just seems really odd to me. I've driven a few cars, including high end race designed cars, but never altered the programming on a car in this way. Is this even possible, or is someone blowing smoke? I have an HP Programmer for the car, but this is not one of the things you can alter with this programmer.

 

[Calaber]

Loren

Don't know about being able to reprogram computers to alter suspension settings on the VE but doubt that it is possible unless you have Magnaride fitted.

Try swapping front and rear wheels over to see if that has any effect. Uneven tyre wear or an internally defective tyre can affect the steering. That might be your problem.

 

[Loren]

This has been from day 1 or as close to day 1 when I bought the car with 15K miles on it. It now has about 51K miles. Hasn't changed over the last 2+ years(?). New Tires, alignment, rotatations, etc. I've been told this may be something to do with the ECM as the "return to center" is controlled electronicly on this model. I've had the "GM Technical Professional" look at the car at the dealer and an independent "GM Expert" who said he would get back to me on it. There has been no "irregular" tire wear, so not sure it is doing anything "bad". Just seems to be really odd behavior.

 

[Calaber]

OK, obviously not likely to be the tyres then. If the ECM controls the steering centering function, that would tend to suggest your car had electronically power assisted steering. I'm not familiar with the VE setup, but would have thought it was hydraulic, operated by a conventional power steering pump.

I guess we need someone with a VE to put something up. Sorry I can't help.

 

[Reaper]

Have done over 200,000 miles (300,000km) over 3 ve's and never heard of or experienced that problem before. I presume the ps pump and fluid levels have all been checked. Could the car have been in a smash from a previous owner?

I did hear of some front suspension issues on US spec G8's that doesn't happen in Aus. All I can think of is the way they are tied down on the boat. Either that or they can't handle water swirling the wrong way down the plug hole up there :s.

Reaper

 

[greenacc]

I've actually seen this on my wifes car, the mechanic pointed it out last time it was in for an alignment. In our case its a subaru and he said it needs a new steering rack mount. Being worn it allows the rack to move a little left and right when its loaded, ie cornering, and won't self centre until you go round another corner or jerk the wheel the other way. Sounds feasible to me so maybe take a look at your rack and make sure its all nice and tight. It could also be a worn bush in your front end i guess ?