Just swapped the old 5.3 for another one with 44k miles. (Cylinder 6 had a small nut grenade in it following an intake manifold gasket job. Apparently the nut was just sitting in one of the extremely deep pits between 6 and 8 in the manifold and popped in number 6 upon sliding the manifold out. It completely destroyed everything in that cylinder, including taking out the spark plug threads.)
The swap was completed Friday, but now there is an ignition issue. Once the engine is warm it requires 8 to 10 revolutions before starting and helps to slightly depress the gas pedal. Once started there is no fluctuation in the idle or any other issue with exception of a possible slight miss. If no pressure is applied to the gas pedal, it will eventually start and the RPMs will be at about 300. For example, it was 32 degrees this morning and it fired strong within a split second of turning the key. Once I stopped at church and got back in, it had to turn over 8 times before firing with a little assistance from depressing the gas pedal.
Since it's a warm ignition problem, I was thinking of an issue with the coolant temperature sensor. My theory being that the engine thinks it's cold, dumps extra fuel, and floods the engine which would explain the great start-ups when cold. The fuel pump is new and there were no issues with that prior to the swap. I'm not sure if the IAC, MAP, MAF, etc., would cause such a problem. Please give your thoughts/experience before I start troubleshooting everything under the hood. Somebody ran off with my volt meter, so I guess I will need to buy another one of those and get the ohms specs for each sensor.
The swap was completed Friday, but now there is an ignition issue. Once the engine is warm it requires 8 to 10 revolutions before starting and helps to slightly depress the gas pedal. Once started there is no fluctuation in the idle or any other issue with exception of a possible slight miss. If no pressure is applied to the gas pedal, it will eventually start and the RPMs will be at about 300. For example, it was 32 degrees this morning and it fired strong within a split second of turning the key. Once I stopped at church and got back in, it had to turn over 8 times before firing with a little assistance from depressing the gas pedal.
Since it's a warm ignition problem, I was thinking of an issue with the coolant temperature sensor. My theory being that the engine thinks it's cold, dumps extra fuel, and floods the engine which would explain the great start-ups when cold. The fuel pump is new and there were no issues with that prior to the swap. I'm not sure if the IAC, MAP, MAF, etc., would cause such a problem. Please give your thoughts/experience before I start troubleshooting everything under the hood. Somebody ran off with my volt meter, so I guess I will need to buy another one of those and get the ohms specs for each sensor.
