Skip the auto shop - Our mechanics make house calls

Q: Trouble starting car when cold

asked by on

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.

A: The starting issues scream timing. The typi...

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Air conditioner works but not fan

Hello. If the air conditioning system is working, but not blowing air, then there may be a problem with the blower motor, or perhaps one of it's associated components. The blower motor is often located inside the dashboard, and sometimes...

Q: Emergency brake light won't stay on. If really cold in the morning, it's out until I drive for about a mile or so

Hi there. Check the cables to the parking brake when you set the parking brake. There is a parking brake sensor attached to the pedal and if the sensor is tripped, the indicator brake light will come on the dash....

Q: The car occasionally won't start

It sounds like a possible fuel overfilling problem, like its potentially flooding. You may be smelling gas or noticing poor fuel economy. The Engine Coolant Temperature (ECT) sensor may have failed or poor connection. There may be a Check Engine...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.