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Q: Trouble starting car when cold

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When it is cold outside, my truck will not start in the mornings. There is not fire. I can put a hair dryer on the motor at the throttle body and get it hot for about hour. My truck will start but it is still hard to start and it backfires through the exhaust. I have put whole distributor, spark plugs, spark plug wires, fuel filter, crankshift position sensor, map sensor, innition coil, innition control module, coolant temperature sensor, runinjector cleaner in it, and tried changing the PCM. I am so dump found out and dont know where to go.It is keeps giving me the codes P0420 and P 1345. I am lost can you please help?

My car has 134569 miles.
My car has an automatic transmission.

The starting issues scream timing. The typical causes that set these codes are the cam and crank position sensors. The only option you have not tried to my knowledge is the camshaft position sensor. I would start there.

With all the recent work that has been done, you may want to start by checking the ignition timing, and verify that the timing is correct. Poor timing can have an effect on the exhaust and be causing the code P0420.

Always double check that ALL previous repairs that were made and verify they are holding. Make sure all the engine timing was set correctly and doesn’t need adjustment.

To avoid any unnecessary repairs, consider YourMechanic, as one of our mobile technicians can come to your home to diagnose your hard starting condition and fix it accordingly.

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