DTC 344 Exhaust back pressure is greater than ECM expected with key on engine off. Scanner shows 2300 PSI sometimes and 3.7 PSI other times does not change with RPM, unplugging sensor, or engine off or on. No rhyme or reason just 2300 or 3.7. Sensor voltage tested at at the ECU is .6 volts key on engine off, 1.1 volts engine idling, 1.6 volts engine at 1800 RPM no load. Engine is suffering from lack of power. I feel like the ECM is faulty. Anybody have a suggestion? Thank You
No replies yet.