Pulls left on normal acceleration

[BumbleBeat]

Like the title says. It pulls hard enough that you have to correct it to stay in your lane. Let off the gas and it pulls back to the right (since you've been holding the wheel "right" to keep it straight). Anybody else experience this? I've had a couple of people say its not unusual for an open diff, but they don't own Beats, and I've sure as heck never experienced it. I've had torque steer on FWD cars with a lot of HP, but those never pulled under normal driving. This seems like a pretty serious differential problem. Thoughts anyone?

[Ohioan]

I am a pretty scary mechanic, but I'm seeing a lot of stuff about alignment or loose ball joints / other suspension components for RWD cars pulling under acceleration. One guy said switch the tires in back if they are nondirectional to eliminate uneven wear or any tire issue. So hopefully it's less serious than a differential.
Some sources:
https://www.s2ki.com/forums/s2000-under-hood-22/car-pulls-left-under-acceleration-then-back-right-decel-1102001/
https://www.driftworks.com/forum/threads/car-pulls-to-one-side-under-acceleration.230789/
A surprisingly interesting and deepish discussion of torque steer in general: http://www.aa1car.com/library/torque_steer.htm
http://www.e90post.com/forums/showthread.php?t=378047
These guys at least say that a scorched diff is the least likely cause: http://www.agcoauto.com/content/news/p2_articleid/249

Anyway, good luck!

[Andrew Fisher]

That's not normal Beat behaviour, that's for sure.

My problem was pulling to the left at about fifty miles an hour if you let off the throttle even a tiny bit. It was fine at speeds below that, and so long as you kept accelerating, it was okay at that speed. (There are limits to how much you can do that.)

When I checked back on old MOTs there was an advisory on rear tyre wear on the inner treads.

The wheel alignment was completely out. I had it done at STS who have the supposed figures for a Beat (PP1 as they call it) and charged £79 (shocking, but in this case they earned it) to set it, with a free recheck a fortnight later. Which I bet 90% of people don't do but I did and it had gone off a bit again, so they readjusted it for free. Their figures were slightly different to the figures you get on this website if you search for toe and camber castor but my car was so far out the figures they have are close enough.

It totally sorted the problem and my car doesn't wander at all now. Like a completely different car.

[stu g]

Check all your bushes and linkages. I had the same problem on a Renault Scenic on which I'd just put a new wishbone. It turns out that one of the bushes was not pressed in right at manufacture so the front left wheel could be wiggled around independently!
Lift it off the ground by the body (front and rear) and try levering things around with a pry bar to see if there is anything loose. Grab hold of the wheels and try wobbling them in each direction.

[BumbleBeat]

Thanks all. I'll be under the Beat this weekend, will take a good close look.

[BumbleBeat]

I had a completely loose track bolt. I assume that's the cause. I haven't driven it--I saw it while underneath digging into the engine due to a knocking rod, ugh. About to pull the bottom case...

[Andrew Fisher]

I had a completely loose track bolt. I assume that's the cause. I haven't driven it--I saw it while underneath digging into the engine due to a knocking rod, ugh. About to pull the bottom case...

You're not having much fun with this car yet are you? I hope you're getting to the end of the immediate to do list.

[BumbleBeat]

No, I am not having fun yet, and the more I do the more I have to do. Got the crank out Saturday, took it with all the bearings to machine shop today, guy says it looks a little worn but doesn't look bad enough to cause any noise. So must be up top. I pulled the bottom with engine in car, didn't want to have to remove intake, exhaust, water lines, electrical. Oh well, another blown weekend ahead doing all that. I would like to have the crank journals measured while its out, but the shop has no idea what they should be of course (in US). Anybody know?