I'm driving an old Grand Voyager minivan temporarily, and notice that when I accelerate then let go of the accelerator, the car pulls slightly to the right, and I have to correct it by steering a little to the left.
What kind of problem am I looking at, and if this isn't indicative of a single problem, what components should I check to determine the problem and the severity?
The vehicle in question is a front-wheel drive. FWDs are sensitive to front wheel alignment, since the front suspension and wheel linkages work under different conditions when accelerating and not accelerating:
This also happens in RWD vehicles, but is limited to the rear axle. Thus, there is no connection between accelerating and steering. A badly aligned front wheel on a RWD will alter steering at all times, not just on acceleration. On a FWD with the steering a bit off, however, the wheels push against the suspension slightly to one side - giving the symptoms you have seen.
The net result is that this vehicle needs the front wheel alignment to be looked at. If it has been going on for some time, it should be apparent as increased and non-symmetrical usage on one of the front tires: one side will appear more used than the other. Besides making vehicle reactions less easy to foresee, it is also lowering tire life since both front tires will need to be replaced at the same time.
I pulled the tires off and inspected the front end suspension and steering, and found that the sway bar linkage on the drivers side was detached.
I've had this behaviour on a number of vehicles and a number of time. Each time it was caused by a different source. These included;
Worn out engine mounts causing the engine / gearbox assembly to move around on and off throttle
Worn out rear wheel bearing so there was excessive play and the rear wheel was effectively causing the car to rear wheel steer itself
Broken bottom ball joint, to part that holds the bottom of the front suspension square
Loose wheel bolts causing movement between the front wheel and the hub
Your issue could be caused by any of the above or something similar. My suggestion would be to first check that all of the tyres are properly inflated, a soft tyre, even on the rear, will cause wayward handling.
If the type pressures all look good, jack each wheel in turn and check for any play by grabbing the wheel at 9 o'clock and 3 o'clock and trying to move it in and out, then at 12 and 6 and doing the same. Spin the wheels by hand and check for anything obvious. Also open the bonnet and watch for excessive movement when revving or releasing the revs from the engine.
If this yeilds no results, take the car for a wheel alignment and mention it to the mechanic who does the alignment for you.
Good luck!
I had the same problem with my hiluc surf (a RWD CAR), what seemed to cause it was the rear breaks on one side (not completely locked) was a bit tighter and every time I stepped on gas the car swung a bit to the side the breaks were tighter
It is called "Torque steering"
The link provides various causes and solutions.
