Hello,
2012 Chevy Equinox with 80,000 miles on chassis and 5,000 on rebuilt engine from a reputable, national builder. Engine was replaced due to excessive oil consumption.
About 8 months after engine replacement, the 2.4 started to idle terribly when cold started and shifted to reverse.
Relevant facts:
New Parts installed during Engine replacement
Watching bank 1 O2 sensor is active and seems in range. I have not replaced the O2 sensor as it appears functional.
I have never seen an ECM replacement solve a situation like this, but we are at wits end here....
General Thoughts on Progression:
At this point, we are leaning towards replacement of the High Pressure Fuel Pump. Any thoughts? Running out of money and patience
Condition seems to go away after the vehicle has warmed up.
Thanks in advance
2012 Chevy Equinox with 80,000 miles on chassis and 5,000 on rebuilt engine from a reputable, national builder. Engine was replaced due to excessive oil consumption.
About 8 months after engine replacement, the 2.4 started to idle terribly when cold started and shifted to reverse.
Relevant facts:
- Does NOT set a code
- Does NOT set a mis-fire
- LT Fuel Trim at -3 after running
- ST Fuel Trim oscillates between -5 to +2
- Seldomly to Plus side
- Does seem to be quite active and all over the board
- Throttle Position responsive and in spec
- Cylinder Balance in spec
- Injector pulse in spec
- Engine Mounts good
- Battery replaced
- MAP replaced
- Traced each connection wire status through the loom
- Checked pins of each connector
- Vacuum leak checks down to the intake manifold with NO vacuum leak
- Nothing from the Fuel Trim indicates a rich condition
- Ran system without EVAP to test for symptom - with EVAP blocked off, symptom persisted
- Tests and system monitor through Snap On Solus Scan Tool
New Parts installed during Engine replacement
- Plugs
- Cam Phasers
- VVT sensor
- Coolant Sensor
- Thermostat
Watching bank 1 O2 sensor is active and seems in range. I have not replaced the O2 sensor as it appears functional.
I have never seen an ECM replacement solve a situation like this, but we are at wits end here....
General Thoughts on Progression:
- Potentially replace high pressure fuel pump
- Potentially replace primary O2 sensor
- Potentially replace ECM
- Potentially replace High Pressure Fuel pump
- Could swap out Cam solenoids; but they are active and within spec
- Thought about a torque converter issue, but if the engine is not running correctly, the tranny will not function properly....and vice versa
At this point, we are leaning towards replacement of the High Pressure Fuel Pump. Any thoughts? Running out of money and patience
Condition seems to go away after the vehicle has warmed up.
Thanks in advance
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