Fuel System - No Start on First Attempt
SI B 13 01 08Fuel System & Control
January 2008
Technical Service
SUBJECT:
M3 S54 - Crank/No-Start on 1st Cold Start Attempt
MODEL:
E46 (M3) with S54
SITUATION
The customer may complain that during the first cold start, or after the vehicle has been parked for more then 6 hours, the engine would crank but not start on the first attempt. The engine will start immediately during the second cranking attempt without any running issues. The problem is currently present and reproducible in the workshop.
No faults are stored in the DME control module. Testing of the fuel pressure, volume and bleed-down pressure do not detect any problems with the fuel delivery system. Also, further diagnosis of the engine electrical components (scope patterns of injectors, ignition coils, crankshaft and camshaft sensors, etc.) shows that all the systems work as designed.
CAUSE
Gasoline fuel blends with low volatility (Reid Vapor Pressure or RVP too low for winter temperatures).
Fuel volatility is defined by ASTM standards and regulated by federal and state legislation. Volatility in different geographical areas is affected by many factors, including state regulations (for example, oxygenated fuel requirements), local altitude, local temperature ranges, refinery capacity, and distribution logistics. Volatility is not related to gasoline octane rating (AKI).
Shifts in fuel volatility occur during seasonal fuel changeover periods. Lower volatility summer fuel (typical range 6 - 10 psi RVP) is changed to higher volatility winter fuel (9 - 14 psi) in the fall, and then back again in the spring.
A cold start situation may occur if a non-homogenous summer fuel blend is introduced into the fuel distribution system and thus the vehicle fuel tanks, when winter fuel is needed.
CORRECTION
Do not replace any components.
Advise the customer to refill the vehicle with a brand name TOP TIER detergent gasoline with a minimum octane rating of AKI 91.
WARRANTY INFORMATION
For information only.
Disclaimer