4.0 doesn't wanna turn over good when cold.

[SolarYellowshortbuss]

My 2003 TJ with the 4.0 has been not wanting to turn over on the first crank when the engines cold it does always start on the 2nd or 3rd crank. Thanks in advance

 

[Tob]

This is a really common issue. It is caused by a lack of fuel pressure due to a failed check valve in the fuel pressure regulator. When functioning correctly, the check valve holds fuel pressure in the fuel line and does not allow it to drain back into the tank or lose pressure.

Try this: turn your key to the on position. The fuel pump will run for a moment. Turn it off, then back to the on position. The pump will run again for a moment. By now you should have enough fuel pressure built up to start on the first crank.

 

[BlueC]

You're going to have to be more descriptive than that. How cold are we talking? If it's slow cranking, how good is your battery?

 

[SolarYellowshortbuss]

You're going to have to be more descriptive than that. How cold are we talking? If it's slow cranking, how good is your battery?

Well not cold more just like not started I reckon and the batterys fine I aint sure if its got anything to do with it but I notice no matter if the engine been warmed up but if my tank is full it seems to start instantly also in terms of slow cranking it cranks fine it sounds just doesnt start

 

[SolarYellowshortbuss]

This is a really common issue. It is caused by a lack of fuel pressure due to a failed check valve in the fuel pressure regulator. When functioning correctly, the check valve holds fuel pressure in the fuel line and does not allow it to drain back into the tank or lose pressure.

Try this: turn your key to the on position. The fuel pump will run for a moment. Turn it off, then back to the on position. The pump will run again for a moment. By now you should have enough fuel pressure built up to start on the first crank.

ill go give it a try when im out for lunch in the case that this is the issue how can I fix it cause I reckon that might get old fast doin that every time lol

 

[Duck Doctor]

ill go give it a try when im out for lunch in the case that this is the issue how can I fix it cause I reckon that might get old fast doin that every time lol

Repair involves dropping the gas tank and gas tank skid then installing a new fuel pump. Not a difficult repair unless your rig is rusted mess. Took me two hours to replace the fuel pump in my LJ.

 

[BlueC]

also in terms of slow cranking it cranks fine it sounds just doesnt start

So when you stated "it's slow cranking", you actually meant it's delayed starting? If so, I think Tob is on it.

 

[Tob]

Repair involves dropping the gas tank and gas tank skid then installing a new fuel pump. Not a difficult repair unless your rig is rusted mess. Took me two hours to replace the fuel pump in my LJ.

From what I’ve read, there are two different check valves, one in the fuel pump and one in the fuel pressure regulator. I replaced the fuel pump and still have the issue. Eventually I will replace the fuel pressure regulator to fix it.

 

[Rickyd]

So when you stated "it's slow cranking", you actually meant it's delayed starting? If so, I think Tob is on it.

Its a pet peeve of mine to hear "turn over" and "crank" used as two different terms. To me they mean the same thing. "Start" or "run" make much more sense in conjunction with either of the previous two

 

[CreepinDeth]

Air, Fiel, Spark

you have been given the advice needed

 

[BlueC]

Its a pet peeve of mine to hear "turn over" and "crank" used as two different terms. To me they mean the same thing. "Start" or "run" make much more sense in conjunction with either of the previous two

Yep, terminology means something. Now, can you recommend some good drum brake pads?