Campaign - Air Intake May Contract Under High-Vacuum
90bmw13 Group 13 Fuel SystemBulletin Number 13 06 90 (3083)
Woodcliff Lake, NJ June 1990 Service Engineering
SUBJECT: Air Intake Boot, P/N 13 71 1 721 431
MODELS: 318is with M42 Engine (through 7/90 production) 318i 4-door with M42 Engine (through 7/90 production)
Situation: Under extreme driving conditions such as full throttle acceleration at very high engine speeds and high ambient/underhood temperatures, a slight reduction of engine power may be noticed after a quick upshift and full throttle application.
Full power capability will be restored by backing off the throttle briefly and applying the throttle gradually.
Cause: The air intake boot between the air flow meter and the intake manifold may slightly contract under momentary high-vacuum running conditions.
Solution: A stainless steel support ring, P/N 13 71 1 734 359 is to be installed inside the boot at the first pleat:
Parts
Information: Description Qty Part Number
Support Ring 1 13 71 1 734 359
NOTE: Support ring is provided at no charge.
Checking: Before delivering a 318is vehicle (produced through production month 7/90) to a customer, or whenever a 318is vehicle visits the workshop, for any reason, inspect the "B" pillar for the presence of Service Action Label # 44.
If present, no further action is required.
If not present, proceed as follows:
Procedure: 1) Remove boot from engine.
2) Install support ring from intake manifold end of boot so that it lies fully within the first pleat. The ring is properly positioned by noting that the ring's inwardly bent ends point to the right of the boot.
NOTE: The boot should have slight traces of oil from crankcase venting on the inside surfaces, which would aid sliding the ring into the first pleat. Additional lubrication should be only in the form of soapy water applied to the ring. Do not spray the boot inside surfaces with silicone or other lubricants.
When the ring is properly positioned in the pleat, no part of the ring should extend into the airflow path except for the tips of the inwardly bent ends.
3) Install the boot; reconnect all hoses.
Service Action Label
Instructions: This Service Action has been assigned code number 44. After the prescribed work has been performed, obtain a label (SD 89-006) and
a) emboss your BMW dealer warranty number in the middle of the label;
b) punch out code number 44 printed on the label;
c) bend label to crease an edge and remove the backing paper. Then affix it to the "B" pillar (on driver's front door) as shown.
If the car affected already has a label from a previous Service Action/ Recall Campaign, affix this new label next to the old one. Do not affix one label on top of another because a number from an underlying label could appear in the punched out hole of the new label.
Warranty
Status: Covered by the terms of the BMW 3 Year/36,000 Mile New Car Limited Warranty:
Defect code: 13 72 01 37 00
Labor operation: 13 54 250 (replace boot)
Labor allowance: 2 FRU
Any questions regarding warranty coverage should be discussed with your District Service Manager.