E82 135i - wheel speed sensors
Discussion
Are these prone to fail all within a short period? I'm on 44k and 3rd wheel sensor in 3 months, I don't know which one this time, but irraitated isn't the word.
Anything else that could be the issue? Dirt, damaged easily, wet weather issue?
So back to dealer Tuesday for another warranty excess charge. I've asked them which ones they replaced previously as I'm not paying excess if same wheel etc.
Anything else that could be the issue? Dirt, damaged easily, wet weather issue?
So back to dealer Tuesday for another warranty excess charge. I've asked them which ones they replaced previously as I'm not paying excess if same wheel etc.
Yeah. Probably a reluctor ring/rings. BMW will want to replace the drive shaft but an indy can do the rings.
The sensors can also be affected by dirt and grime e.t.c. so can be fixed with cleaning if that is the issue but considering your failure rate, I reckon the rings are the issue.
The sensors can also be affected by dirt and grime e.t.c. so can be fixed with cleaning if that is the issue but considering your failure rate, I reckon the rings are the issue.
I had this issue on my E90 3 series. My symptoms being that DTC would occasionally cut in when driving on an incline. Eventually it got worse and for a short time I was able to get around it by switching DTC off, but that's not ideal in winter!
I suspected the wheel speed sensors to be at fault, so as the car is rear wheel drive I had a poke around there first. Sure enough, the face of one of the sensors had worn away matching the curvature of the reluctor ring on the drive shaft. The shaft showed some corrosion, so I thought perhaps this had caused the reluctor ring to expand until it made contact and wore the face of the sensor away.
BMW and local independents wanted several £££'s to supply new driveshafts, rings and sensors but as the car is 10 years old and has 150k miles on the clock I wasn't interested in spending that kind of money if I could help it.
@mikeyscott It seems weird to me that a garage would just fit a new sensor without any thought, because obviously in a very short amount of time the new sensor will wear and you will get the same fault. It's no wonder you're on your 3rd sensor!
The most cost effective solution seems to be this:
1. Buy new sensor.
2. On the body of both new and old sensors, use a vernier caliper measure distance between mounting face & sensor face. There will be a small difference due to wear on old sensor, let's say this is 1mm.
3. Install the new sensor, but use some shim (M5 washer may do) to space the sensor away by 1mm + 0.5mm additional clearance. This will ensure a gap of 0.5mm between sensor and ring.
4. Take it for a drive and after a short distance, the warning light should disappear.
This worked for me; the DTC works absolutely fine and I haven't had a warning light in 2 years. A year later the same fault happened but on the far side of the car and I fixed it again the very same way.
The cost is only the price of a new sensor and it takes less than an hour to fix.
I suspected the wheel speed sensors to be at fault, so as the car is rear wheel drive I had a poke around there first. Sure enough, the face of one of the sensors had worn away matching the curvature of the reluctor ring on the drive shaft. The shaft showed some corrosion, so I thought perhaps this had caused the reluctor ring to expand until it made contact and wore the face of the sensor away.
BMW and local independents wanted several £££'s to supply new driveshafts, rings and sensors but as the car is 10 years old and has 150k miles on the clock I wasn't interested in spending that kind of money if I could help it.
@mikeyscott It seems weird to me that a garage would just fit a new sensor without any thought, because obviously in a very short amount of time the new sensor will wear and you will get the same fault. It's no wonder you're on your 3rd sensor!
The most cost effective solution seems to be this:
1. Buy new sensor.
2. On the body of both new and old sensors, use a vernier caliper measure distance between mounting face & sensor face. There will be a small difference due to wear on old sensor, let's say this is 1mm.
3. Install the new sensor, but use some shim (M5 washer may do) to space the sensor away by 1mm + 0.5mm additional clearance. This will ensure a gap of 0.5mm between sensor and ring.
4. Take it for a drive and after a short distance, the warning light should disappear.
This worked for me; the DTC works absolutely fine and I haven't had a warning light in 2 years. A year later the same fault happened but on the far side of the car and I fixed it again the very same way.
The cost is only the price of a new sensor and it takes less than an hour to fix.
Username... said:
@mikeyscott It seems weird to me that a garage would just fit a new sensor without any thought, because obviously in a very short amount of time the new sensor will wear and you will get the same fault. It's no wonder you're on your 3rd sensor!
Not weird at all with a BMW dealer.Computer says replace part A, not ask the question, why is part A repeatedly failing?
Ben there, done that, have the tee-shirt etc.
aeropilot said:
Not weird at all with a BMW dealer.
Computer says replace part A, not ask the question, why is part A repeatedly failing?
Ben there, done that, have the tee-shirt etc.
That's why I was reluctant to take my car to a garage for diagnostics myself.Computer says replace part A, not ask the question, why is part A repeatedly failing?
Ben there, done that, have the tee-shirt etc.
Sure diagnostics can be very useful, but in my experience if you rely on a dealer it just leads you down a path of replacing random parts. Usually starting with the most expensive part first! Like you said, there's often no thought about finding the route cause of the problem.
I'm not a car mechanic, but a mechanical engineer in a completely different field. I find that if you take the time to learn how things work on a car, aside from electronics, cars are pretty simple really. I've diagnosed & replaced the turbo, removed swirl flaps, renewed the intake manifold & EGR, and plenty more.
It just amazes me that there are so many bad mechanics out there. Find a good one and they're often priced accordingly!
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