At this point, the powertrain had been fully serviced. Nearly all the codes in the DME were gone, the motor and transmission felt healthy, and I was starting to see the light at the end of the tunnel. Unfortunately, driving to the end of that tunnel in a straight line was a terrifying proposition. Even after all our bonding, the 128i was still trying to kill me.
It took me a while to articulate exactly what the problem was. This car wandered on the road so much that it made an old, worn-out YJ Jeep Wrangler feel like the epitome of confidence and freeway stability. The car was seemingly unresponsive immediately off-center and would make a noise, as though something was loose, if you shook the wheel back and forth quickly (while stopped). When you did shake the wheel at a stop, there seemed to be a massive dead spot in the center of the wheel.
As a result, if I turned the wheel just a hair while driving, the car wouldn’t respond, seemingly requiring me to turn it further. When it finally did respond, it would turn far more sharply than anticipated, making it very difficult to keep the car in its lane. Instead of a smooth change of direction when turning the wheel, keeping the car pointed straight felt more like a violent game of ping-pong.
Unfortunately, I’m a slow learner and didn’t pick up on the subtle clues the car was giving me at first.
My first instinct was to get the car to the nearest alignment rack. What I should have done was pull out the string and the wrenches, but instead, I lazily opted to pay a local tire shop with a rack. More on that later.
They adjusted the toe quite a bit, furthering my suspicion that one of the previous owners had lowered the car and returned it to stock without bothering to re-align it.
These fine folks claimed they couldn’t get the right rear toe into spec. As mentioned in a previous post, the only modification to the car was a set of rear aftermarket adjustable toe arms. I later discovered that they never touched the aftermarket toe arms and instead relied solely on the factory eccentric adjustment bolt to adjust rear toe. Yes, that’s right—I paid someone money for a job I ultimately had to fix myself. That’ll teach me to be lazy!
While the alignment was certainly improved and the dartiness was mitigated to some degree, the car was still terrifying to drive. You could say our relationship still had some serious trust issues.
My next thought was to check the tie rods, control arm bushings, and ball joints.
Sure enough, one of the right rear upper "wishbone" control arms had a bushing that was completely shot. I could feel the play in it with barely any effort.
At this point, I had some options: I could replace the worn arm with a standard replacement, or I could dive deeper into the parts bin rabbit hole and throw some upgrades at the car. You can probably guess where this is going.
I discovered that several control arms from the BMW E90/92/93 M3 and BMW 1M bolt right up to my humble 128i. Even better, they’re manufactured by TRW, an OEM supplier for BMW. The best part? You can purchase the TRW-branded versions from companies like FCP Euro at half the price of the BMW-branded parts. The only difference is that TRW scratches off the BMW part number. Ironically, these upgraded TRW parts are similarly priced to the lower-spec stock pieces.
The M-car control arms have several advantages. In the front, they push the lower knuckle out slightly farther, adding approximately 0.75 degrees of negative camber. The base front control arms are fluid-filled and prone to leaking over time, whereas the M-arms use a sealed spherical bearing for greater handling precision.
In the rear, the base "upper wishbone" arms are stamped steel, while the M replacement arms are solid aluminum. While I’m speculating, I suspect the M parts also use a hardened bushing for added durability.
Installing the front control arms was a straightforward job with no real "gotcha" moments. You can even see where TRW dremeled off the BMW part number to sell these at such a significant discount.
Despite having 133,000 miles on the clock, the old front control arms weren’t in terrible shape. The bushings showed no signs of leaking, and the ball joints didn’t exhibit significant play—at least not enough to account for the car’s instability issues.
In the rear, I previously mentioned hearing a whirring noise from the right rear wheel. Initially, I assumed it was a bad wheel bearing, but when I inspected it by shaking the wheel while the car was lifted, there was no play whatsoever. Not knowing whether the previous owner had replaced everything in the right rear wheel well or reused parts after the accident, I decided to replace everything for peace of mind. Back to eBay I went.
I ordered a complete used right rear assembly, including the knuckle and various links/control arms. I paired this set with the brand-new TRW M3/1M upper wishbone arms I had purchased from FCP Euro.
Upon pulling the knuckle, I discovered the source of the whirring noise: the inner lip of the right rear axle was severely chewed up. This damage was likely catching air during driving, producing a sound similar to what you'd expect from a failing wheel bearing. With the issue identified, I paused the project for a few days while waiting for a replacement axle to arrive from Rock Auto.
After a few tedious (read: unpleasant) hours of work on jack stands, I managed to swap everything over successfully.
Since I had already planned to install a new rear right wheel bearing, I decided to go ahead and replace it while everything was torn apart. With the bearing in hand and the knuckle/bearing housing prepped and greased, I got to work.
Those shiny new aluminum TRW M3/1M upper wishbones definitely spruce up the rear end of this dirty E82!
I have a confession to make: most of my garage time has been spent fumbling around with lighter Japanese cars. Installing the new wheel bearing on the E82 was the first time I encountered a torque spec over 300 ft-lbs! This meant it was time to upgrade my tools, so I invested in this massive 3/4" torque wrench behemoth.
At this point, the right rear side had been fully rebuilt. New TRW M3/1M control arms were installed at all four corners. I used mostly new hardware and torqued everything to factory specs. The result? Yep, still trying to kill me.
Next, I replaced the tie rods, hoping they might cure what ailed the car. No luck—she was still out for blood.
It was around this time that I dug my thinking cap out of its dusty basement corner and decided to actually use it. I began focusing on the noise I heard when turning the steering wheel back and forth, coupled with the rack's lack of immediate response.
I crawled under the car with a mechanic’s stethoscope while my son turned the wheel. Listening carefully, I pinpointed the noise—it was loudest at the rack and pinion, where it connects to the steering shaft.
As an experiment, I tried tightening the bolt to increase tension in the rack. All this accomplished was adding creaking noises, increased resistance while turning, and reduced self-centering. Spoiler alert: I don’t recommend this “solution,” but hey, science demanded I try it.
Next, I found a thread on E90Post/1Addicts discussing how the steering shaft bolts can come loose over time. I torqued the bolts down to spec, hoping for a breakthrough. The top bolt was slightly loose, but the bottom one was tight. After re-torquing both, the car’s behavior remained unchanged.
After running through every possible diagnostic and firing the parts cannon in every conceivable direction, I finally bit the bullet and ordered a fully rebuilt steering rack and pinion from Rock Auto. A new rack was briefly considered—until I saw the price tag, which nearly gave me a heart attack. It cost almost as much as I’d paid for the car!
I also ordered a brand-new aluminum steering shaft. Unfortunately, there are no cheap aftermarket replacements or rebranded OE options for these cars. If you want a new one, you have to swallow your pride, open your wallet, close your eyes, hit “Order,” and try not to think about it.
In a classic case of “while I’m in there,” I added a reasonably priced OE power steering reservoir from FCP Euro, along with all new hardware.
The installation process wasn’t bad. It was surprisingly straightforward after watching a couple of YouTube videos. Once everything was buttoned up and functioning as designed, I bled the power steering system and took the car for a test drive.
Finally. After tearing the car apart at all four corners, the steering was fixed, and the car no longer seemed intent on planning my demise!
Since I had to remove the OEM airbox to access everything, I took the opportunity to make a couple of small upgrades. First, I removed the charcoal filter and replaced the factory intake elbow with a new Turner Motorsports silicone elbow connecting the airbox to the throttle body. According to the internet, this mod might be good for a couple of extra ponies. Of course, we’re talking Shetland ponies here—not Clydesdales—so I didn’t expect to notice a real difference.
While the airbox was out, I used a Dremel and sandpaper to smooth the transition where the charcoal filter used to sit. It was a mildly satisfying task, even if I didn’t feel any tangible improvement in power or throttle response.
With all the steering gear buttoned up, I finally did what I should have done from the start: I put the car on blocks in the garage, grabbed some fishing wire, a ruler, a notepad, and got to work dialing in the toe alignment myself.
When I got to the rear of the car, it became painfully obvious that the tire shop I had previously gone to hadn’t touched the aftermarket toe arms during their alignment. I adjusted them myself until the rear was within spec. Funny enough, I had a stock toe arm sitting around in the garage (it came with the replacement rear knuckle). After dialing in the aftermarket arms to spec, I measured their length—and wouldn’t you know it—they were identical to the stock toe arm! Imagine that.
Just to confirm my work, I took the car to a different tire shop to double-check the alignment. As it turns out, my DIY string alignment in the garage was spot on!
The alignment rack also confirmed that the TRW M3 / 1M front control arms added almost a full extra degree of negative camber in the front! After spending a considerable amount of time in the garage, the 128i now drove as straight as an arrow! We had worked through our relationship issues, and it felt like we were finally building a future together. A funny thing happened around this point: I started to really like this little car. I found myself driving it almost everywhere, relishing the satisfaction of transforming what was once a terrifying pile of bolts into a legitimately enjoyable vehicle. Not to worry though, as good as the car was becoming, there's still more to be done. A lot more.
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