Engine - Rough Idle
GROUP 11Engine
Bulletin Number
11 07 98
Woodcliff Lake, NJ
September 1998
Product Engineering
SUBJECT:
Rough Idle
MODEL:
All with M44 engines
Situation:
A rough idle may be observed with the engine at operating temperature due to unfavorable valve timing tolerances during the valve overlap phase.
Note:
The engine idle quality should not be evaluated before a mileage of approximately 3000 miles is accumulated thus assuring complete engine break in.
Correction:
If a customer complaint of a rough idle with the engine at operating temperature is received and all engine parameters meet BMW specifications (no ignition problems, no unmetered air leaks, no fuel supply problems, cylinder leak down is less than 15%, etc.) readjust the camshaft timing using the new intake camshaft alignment tool Part Number 90 88 6 119 110.
Note:
The modified intake camshaft timing is only intended as a customer complaint field fix and will not be phased into production.
Procedure:
Readjust the camshaft timing as outlined in the E36 M44 repair manual, section 11 31 005 using the new camshaft alignment tool on the intake camshafts shown in the illustration.
Parts Information:
The new tool has been designed to retard the intake camshaft timing by 6( and will not lead to any perceptible drop in engine torque or power output.
The new intake camshaft alignment tool Part Number 90 88 6 119 110 has been sent to all BMW Centers via automatic tool shipment.
Refer to Service Information bulletin 04 07 98 for further information.
Warranty Information:
Covered under the terms of the BMW New Car Limited Warranty.