2000 BMW 328i (E46) Technical Service Bulletin # 340798 Date: 990701
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Brakes - Twitch in Steering Wheel With Rapid Application
Group 34
Brakes
Bulletin Number
34 07 98
Woodcliff Lake, NJ
July 1999
Product Engineering
This Service Information bulletin supersedes S.I. 34 07 98 dated October 1998 which should be removed and discarded from your S.I. binder.
Changes to this revision are identified by asterisks.
SUBJECT:
"Twitch" Felt in Steering Wheel on Rapid Brake Application
**MODEL:
E46 Not Equipped with DSC**
Situation:
Some E46s can encounter a customer complaint of a very slight "twitch" that can be felt in the steering wheel when the brakes are applied rapidly.
This is felt most frequently if the wheel is held very lightly with one hand, and the brakes are given a quick tap. The wheel will twitch slightly once,
with no disruption of stability of the car, and no pull to either side.
Cause:
This complaint can be caused by having unequal amounts of toe-in on each front wheel, or it can be caused by a very slight time differential in the
build up of pressure in each front brake caliper.
Correction:
In case of customer complaint, and the alignment is known to be correct, a dampener can be installed to modify the brake pressure build up curve.
**Note:
The dampener cannot be installed on DSC equipped cars as it will DSC operation. **
Procedure:
Place brake pedal holder on brake pedal.
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Draw off brake fluid from reservoir and remove reservoir.
Disconnect line to front brake circuit (A). Note: This is the line closest to the booster.
Install dampener (B) into port in master cylinder, and tighten to 17-19 Nm.
Connect brake line (A) to dampener and tighten. Note: It will probably be necessary to pull up on the line so that proper alignment with the
dampener can be achieved.
Reinstall brake reservoir. Bleed brake system with DIS machine.
Parts Information:
This repair requires the following:
Part Number Description Quantity
34 31 6 750 384 Dampener 1
In addition, a maximum of one liter of brake fluid is required.
Warranty Information:
This repair is covered under the terms of the BMW new car warranty.
Defect Code: 34 00 91 57 00
Labor Operation: 00 51 419 Install dampener and bleed
Labor Allowance: 15 FRU