Mitchell1 Tech Tip: Stuck Buick Turbo

Mitchell1 Tech Tip: Stuck Buick Turbo

Sometimes you go through all the documented testing steps for a problem and still can't find the solution. When this happens, turning to your fellow techs is a great solution.

2011 Ecotec 2.0L I-4 VVT DI Turbo (LHU) for Buick Regal CXL Air and Exhaust Flow – David Kimble Illustration. The E39 engine control module controls all the functions of the Ecotec 2.0L turbocharged engine including the direct injection fuel system, continuous variable valve timing for both intake and exhaust valves and the turbocharger.

Vehicle: 2011 Buick Regal CXL Turbo 2.0L

Complaint: The customer stated the check engine light was on.

Code: P2261 Turbo Bypass Valve Stuck Closed

Sometimes you go through all the documented testing steps for a problem and still can’t find the solution. When this happens, turning to your fellow techs is a great solution. SureTrack community member candtauto had a Buick Regal Turbo in the shop with a code P2261 for a stuck turbo bypass valve. They posed the question to the community, and with the help of fellow community member dmckemie12 and others, they were able to resolve the issue quickly.

Diagnostic Steps Performed/Parts Replaced: The technician checked for codes and found code P2261 for Turbo Bypass Valve Stuck Closed. Replaced bypass valve and solenoid, smoke tested found no leaks. Substituted good MAF and MAP sensor. The MAP was reading 15 at idle and the vacuum gauge reads 11 PSI when cold. If the throttle was snapped, it would go to 18. There was no audible sound heard when the throttle was snapped, and the valve appeared to be working.

Best Answer from Community Member: The vacuum tank also has an internal check valve, make sure it is working.

Cause: Vacuum tank was the cause.

Correction: Replaced vacuum tank, cleared codes, and tested vehicle. The code did not return.

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by Nick Taylor

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