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Q: After engine sets for 6+ plus hours it hardy starts

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The truck turns over like it should but after overnight setting it takes multiple attempts to start. Just changed all fuel injecters and the coils n plugs are less than a year old. Fuel pump is less than 2 years old. I had a hit and miss problem with missing coolant and plugs may have have a slight green tint. Truck runs and starts great after warmed up. P 0172 is code but tail pipe is off truck.

My car has 105317 miles.
My car has an automatic transmission.

In most cases, the P0172 error code indicates that there is too much gasoline being detected in the exhaust gases exiting the combustion chamber. The ECU uses a number of instruments, such as the mass air flow sensor (MAF), oxygen sensors, and manifold absolute pressure (MAP) to monitor the air-fuel ratio of the engine. Having the tailpipe off the vehicle could cause this problem to occur, since the vehicle’s engine is tuned to have the entire exhaust system attached.

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