new owner of an 04 R53 S and of course I'm like most others here... Starting with the trifecta. Now I've done my searching, investigated the problem, thrown parts at it as well as cleared the faults. no luck. Please read.

Have the Abs light, traction light and occasionally the tire pressure light.

Bought a C310 scan tool and scanned to find a faulty front left Front ABS sensor. This is the only fault stored. Although there are multiple codes it only says L/F Abs sensor. I installed a new Ebay ABS sensor and then cleared faults. Nothing changed.

I was going to reinstall old ABS sensor and try clearing faults but the socket that holds the sensor fell apart. I was also told that it could possibly be a bearing/hub issue even if I couldn't diagnose it as such. At this time it also needed front pads and rotors.

So, I installed new ABS socket to replace the crumbling old one, R/R front pads and rotors, R/R left front hub assembly, R/R the front motor mount at the same time. While I had everything off I inspected the eBay ABS sensor to make sure it wasn't damaged or dirty. I even shopvacced the inside of the ABS sensor port where it sits in the hub to hopefully remove any debris that I couldn't see or remove when I cleaned the area.

Cleared faults again and test drove. Lights didn't go out. But it drives much better because of replacing the front motor mount. Although I wont drive the car like this.

The question is should I order another ABS sensor and try that or assume its possibly an ABS unit that is causing this and just give up?

 

How old is the battery? Sometimes you will get lights when there is marginal voltage.

 

no date listed on the battery. It does seem to be cranking slow. I put it on a trickle to see if that would help but it didn't change. I guess I'll try swapping it out soon.

 

Some batteries have letter codes for dates. C2 could be March of 2012, H4 could be October of 2014

 

Looks like this has been moved to the "stock/problems issues" although I think there may be something about a modification causing this issue.

Let me start from the beginning since there has been some developments. Some of this may be what I explained in the previous post.

When I bought the car about a month ago the previous owner told me he had checked the light trifecta and that it was one of the ABS sensors. Since it was such a common issue I just believed him and then scanned the car myself after purchasing. It was listed by my newly purchased Creator C310 scanner as a left front ABS sensor. 2-3 weeks had passed between when I bought the car and when i installed the sensor. I put a few hundred miles on at this time and there was absolutely no change with the lights. They didn't go off at all, flash or otherwise. They were constant. However the car on just wet ground was terrifying to drive. I mean scary. Wasn't even raining, just wet.

1 week ago, immediately after the sensor install, I cleared the faults and test drove the car. Nothing happened. Then I cleared the faults again and the Tire pressure light went out. Coming out of my garage all 3 lights went out. At the same time i slowed down and hit the brake pedal. The second i pressed the pedal the ABS kicked in and it just felt like the pads were jumping off the rotors. I was only going about 2 miles per hour in the dry so I don't know why ABS would be doing that. I kept driving and the lights popped right back on after 100ft or so and the braking felt normal again.

Hoping it was just a connection issue with the newly installed sensor I tried to remove it and this is when the ABS sensor socket fell apart inside the new sensor. So I ordered a new OEM socket. Installed the new socket, replaced front pads and rotors(since they were due), replaced the front left hub since this could also be attributing to the problem and tried my hardest to make sure the connections were good and that no wires were torn or frayed. I cleared the faults and test drove. Obviously since the front brakes are new it feels even better braking. But there was still no change with the lights.

Earlier today the car had been sitting for a little over an hour after driving for a few miles. It cranked right over and when I pulled away the 3 light indicators again decided to go out and the ABS kicked right in and I could feel the pulsation in the pedal and in the front of the car coming to a slow stop while only driving a few miles per hour. I drove 5 miles parked for about 2 hours, and started driving again. A little over 500 ft later I went over a normal size speed bump very slowly and the lights went out, car became sluggish and the traction light started to flash. I started to accelerate slowly and the lights came right back on.

Extremely sorry for the short novel but Im hoping that there is some other indication of a known issue. Because whats going on couldn't be attributed to a faulty sensor alone.

Im willing to try a battery however, with the cost of the battery Im hoping there is more of an answer to this rather than guessing that its just a battery. I did check and the battery is only about 2 years old. Ive got it on a trickle in the garage as of right now.

I plan to work on things it needs as I get the cash and time to do them but this sensor issue alone is killing me.

Known Mods-

Header back exhaust. added a pic of the catback portion.
(irish or something and the alignment is terrible in the rear. mid pipe is so crooked and they cut the exhaust tip hanger to make it fit.)
Lowered with springs only. I don't know the brand but they are green. If i had to guess without measuring there is probably about .50"-.75" gap between tire and fender.
tops of the strut towers are mushrooming and could use those defender/reinforcement plates.
Riding on 16x8.5" Wagen wheels with 245/50 tires.
tires show marks at the edge of the tread from when it rubs. Doesn't take much.
Cold air intake box? (whatever brand has the clear cover for the filter.)

 

If you have questions on the battery suggest you take it to an autoparts store. They can test and tell you if the battery is good or not.

 

As I suspected it is not the battery or alternator.
Voltage : 12.53V
Measured: 1236 CA
Rated: 810 CA
good battery

Charging System
No load 14.04v
Load 13.89v
normal


While driving I plugged in my C310 scan tool to read the data stream for the wheel speed sensors.

It showed -
Left front - 0.64kmh (it would also intermittently have different readings)
Right Front - 94.0kmh
Left Rear - -94.36
Right Rear - 94.07

at a stop/idle the sensors read -
Left front - 0.64kmh
Right Front -0.64kmh
Left Rear - 0.64kmh
Right Rear - 0.64kmh

The problem here is that at idle the Left front sensor intermittently jumps to different kmh and then back to .64kmh. The others stay at .64kmh

before today when I scanned it it only showed a Left front wheel speed sensor fault. Now it also includes a fault 5DF0 "Return Pump"

Im just about ready to jack up the battery and replace the car.

 

I'v seen ABS sensors on ebay for as low as $11.00. You going to try at install a new one?

 

i just ordered another. I'm doubtful though. Appreciate the response.

hopefully will update with good news

 

Check the connections. The sensor is tracking the drive shaft location at the hub, so wondering if you moved the shaft in an out a little after loosening the hub whether it would impact anything as well.

 

Those lights came on when my crank pulley was failing. Do you know when your's was replaced?

 

I don’t know. just purchased from a private dealer who had no history of the car. Currently 100,850 miles.

 

Loosen the drive belt and see if you can push the crank pulley in so that it contacts the motor. If there is movement in the pulley and with those miles it may be time to change.

 

Well Im stoked!

I got unlucky and had a bad sensor to replace the old one with. The only reason I was hesitant was that the abs sensor socket crumbled when I installed it so I had to replace that as well. So I thought it could have been something with a connection or polarity. Because the sensor crumbled I was hesitant to try and swap the one on the other side.

r53coop, thanks for the confidence to just throw another sensor at it. Sincerely appreciated.