Trailblazer troubleshooting:
This all started with a po203 code for injector 3
The issue: It fires right up and the cylinders that work run smooth, cylinders 3 and 4 do not run I believe it to be electrical related but am unsure
Whats known: it gets spark and fuel, and all coil packs are receiving the appropriate 12 volt power
What I've checked/replaced: its not coil packs, spark plugs, injectors, cam angle sensor, computer
Next things to check: injector harness, wiring harness, crank position sensor, vvti sensor, maybe knock sensors, compression test
This all started with a po203 code for injector 3
The issue: It fires right up and the cylinders that work run smooth, cylinders 3 and 4 do not run I believe it to be electrical related but am unsure
Whats known: it gets spark and fuel, and all coil packs are receiving the appropriate 12 volt power
What I've checked/replaced: its not coil packs, spark plugs, injectors, cam angle sensor, computer
Next things to check: injector harness, wiring harness, crank position sensor, vvti sensor, maybe knock sensors, compression test
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