[richas]

I have had my 328xi E91 for several months now. I have fixed many minor issues, oil leaks, replaced the valve cover, and replaced the defective VANOS bolts. There are a couple issues that I would like to address.

The car surges forward when cold sometimes. (Automatic) Only within the first minute or so of driving, when you foot is off the gas. For example when I am descending my driveway. It will really jump, you have to be quick on the brake. Runs normally otherwise, nice smooth idle. No codes.

The car tracks oddly on the highway sometimes, following deformations in the road and sometimes seeming twitchy, not wanting to track a straight line sometimes. I have inspected the front suspension and nothing jumped out. Couldn't find significant play in balljoints or bushings. But sometimes that is hard to find... Time for a suspension refresh of some kind? (97k miles) Tire wear appears even.

Thanks

Rich

[StuKatz]

Our E91 has similar symptoms, twitchy , no noticable tire wear. these isses all went away after a wheel alignment

[tlow98]

At 100k you certainly could use shocks, mounts etc but it’s likely not totally necessary. But it will make you love the car if it’s fresh.

The jumping is a little odd but I’ve experienced that if I start the car and quickly move to park or reverse. Are you letting it idle for 30 seconds first?

[Mike K]

My e91 hops a bit if I quickly slam it in gear right after a cold start. I go easy after a cold start typically.

[richas]

Yes, I think you guys are right, I do pop right into gear and go. I will try giving it a half a minute to warm up, I bet that takes care of it.

The tires are about 70 to 80% worn so when I get a new set I'll get an alignment and see if that takes care of things. The shocks were replaced not too long ago.

Rich

[TriumphTim]

I purchased a car with similar miles a few years ago, auto 328xi E90, to daily drive.

I would recommend doing the trans fluid/transfer case fluids and reset adaptations for shifting smoothness. Shouldn't need warm up, I get in and go but drive slowly for a while.

I would recommend keeping an eye on the coolant hoses and starter, all which failed for me around 100k miles.

Tracking problems went after alignment and replacing front tires, the fronts were driven out of alignment so long by PO they went to the cords quickly after correction.

Some suspension components are probably at the end of their life, my rear shocks were 100% blown at 97k.

[richas]

I'm following up on this again with relation to the jump forward when starting out cold. It's still doing this, it did it two days and scared the crap out of the whole family. I'm wondering if it's the torque converter locking up.
I think the transmission is due for its first service, perhaps that will help…

Rich

[e91Owner]

Certainly time to change the fluid/filter anyway at that mileage. The GM transmission is clunky even when freshly serviced, so I'm sure it's due. On my trans last service, I used Valvoline maxlife plus a couple of tubes of shudder fix. Much smoother than the redline D6 that I had used previously. Just make sure to read over the tons of horror stories about the fill plug before trying to remove it, if it's the first service and replace it with the GM plug as opposed to the soft BMW one. FWIW

[Serf27]

My n54 e90 did this.
I don’t remember having any codes, but somehow came to the point of replacing the crankshaft sensor and that solved it. Quite scary when you’re going very slow!