M4gery4x4

yea aint that the truth lol, least that prob is solved course now that its been gettin colder out ive started havin an intermittent crank but no start prob that i think is either my fuel pump or a loose coil so yay...

Jbrew

Don't feel bad about purchasing that alternator. I purchased a battery when mine was doing it lol. But, at the the time, I was also having a no crank problem. It would crank and start if I had the key on, but only if I crossed the relay on the firewall. My connections all looked real clean, but some must have been oxidized. The copper connections can oxidize enough to disrupt connection. You can't always see oxidation. After wire wheeling the connections again...no more problems.

So when you say intermittent crank, that means to me that it doesn't always crank. If that's the case, make sure you go over the connections well, hit them with a brush just to make sure. There's not much else it could be. Tell you what, next time it doesn't crank, - leave the truck in park, turn the key to the run position, then cross the stater relay on the firewall with a big screwdriver. If it cranks and starts, that's usually a connection issue IMO. Could be ignition, but hit the connections real well first.

BTW, - That recommendation only applies if I'm understanding your problem correctly.

M4gery4x4

yea i tried checking some of the connections they seem fine but i need to go back and check more thourough, thing is i can't always hear my fuel pump prime and sometimes its louder than others, plus when i had my fuel filter replaced a few months ago i was told that i had low fuel pressure since there was only a trickle of fuel in the line when they took the filter off. and yea by crank no start i mean it always cranks fine it just will randomly decide not to fully turn over

Jbrew

So it's slow like a dead or low battery? Or do you mean start? I think you mean start. Since they can turn over and fail to start. Semantics lol.

Definitely sounds like the pump. When you turn the key to run and IF you don't hear the pump, leave the key in run and hit the bottom of the tank with something. If you then hear the pump prime/charge the lines, yea it's the pump. That's exactly how they go out most of the time. The pump fails to turn/start.

Also fuel pressure can't be below 29psi or it can't keep up. anywhere below 32psi is when the pumps on it's last leg.

M4gery4x4

yea it cranks normal just doesnt fully turn over, when it does that gotta try 3-4 times and itl finally start. batt is only about a month old anyways. think il just test the fuel pressure and see where its at and hopefully thatl help

Jbrew

So by turn over, you mean start correct lol. Turn over is what the engine does before it starts.

Yea, you can't crank these engines for more than 4 seconds at a time. The PCM shuts the rail down to protect the cats. I guess that info might help some.