U257A Pontiac Bonneville DTC Code

Pontiac Bonneville Engine Specifications:

Engine Type :	Single Cylinder Engine
Cylinder Type :	Opposed Cylinder Engine
Engine Air Intake Process :	Naturally Aspirated

Your Pontiac Bonneville engine control system detects a problem, the computer stores the diagnostic trouble code U257A in its memory. To figure out what is wrong with your vehicle you must first extract the U257A DTC For Pontiac Bonneville.

A good ground connection is also extremely important. U257A Pontiac Bonneville engine problem because the presence of voltage at the panel harness won't make the panel work if there is a bad ground connection. Since the instrument cluster is mounted in a plastic dash, a separate ground wire or ground circuit through the wiring harness is usually needed to complete the power circuit. Refer again to the wiring diagram to find the ground path, and then check it with your ohmmeter. Do not use a self-powered test light because it cannot measure resistance (any resistance will lower circuit voltage).

U257A Pontiac Bonneville DTC Meaning

U	Network Code - Problem is climate control system, lighting, airbags, etc.
2	MFG - Manufacturer Specific
5	Auxiliary Emission Controls
7	Exhaust Gas Recirculation System Valve 1
A	TFP Valve Position Switch-Drive Without Drive Ratio

While fuel economy was increased, acceleration was seriously compromised, and the loss of engine vacuum led to a dangerous loss of braking assist when the U257A Pontiac Bonneville code system was in four-cylinder mode. In addition to these issues, while the company proposed a hydraulically controlled system that could be switched from within the car, the version they implemented had to be manually changed in the engine compartment using hand tools.