GM Service Manual Online
For 1990-2009 cars only

Crank No Start After Parking On An incline When The Fuel Levels Are Low - keywords hill intermittent tank

Subject:Crank No Start After Parking On An Incline When The Fuel Level Is Low

Models:2008 Buick Enclave
2007-2008 GMC Acadia
2007-2008 Saturn Outlook



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some customers may comment of an intermittent crank no start, or start and then stall when the fuel level is low (typically less than 1/8th tank) and the vehicle is parked for an extended period of time (more than 12 Hours) on an incline. The design of the fuel tank will allow fuel to migrate to the end of the tank when the vehicle is parked on an incline, not allowing the fuel system to draw fuel from the tank because the fuel pick up is no longer submerged in fuel. If the fuel pump module reservoir check valve allows fuel to leak out of the reservoir, insufficient fuel will be available to start the vehicle or allow the engine to run following a start. Since the fuel has leaked out of the fuel module reservoir, and the fuel is not available at the fuel pump pickup in the tank, no fuel will be available to be drawn into the fuel system. If fuel is added to the tank or the vehicle is rolled to a flat surface, the vehicle will start because the fuel module is now submerged so the pump can draw from the fuel.

Recommendation/Instructions:

Do not make any repairs for this concern at this time. Engineering is aware of the concern and is working on a fix.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.