Hey guys, my truck is giving me some grief lately, On sat, I cleaned the battery terminals, with baking soda and water/stiff bristled brush. Then I went in to town, no problems, got home, washed the truck, polished the wheels, then it wouldn't start. Had lotsa juice, cranked over for a while, but wouldn't go. I left it, went out for the night, and it fired right up the next day.
I drove it again on wednesday, it fired up and ran normal for a while, then randomly wouldn't start again. Cranked it over enough times to drain the battery. Nothing. I had it towed home yesterday, charged up the battery overnight and she fired up no problem? I just installed a fuel pressure gauge today, with the FASS, I'm getting 10-11psi at WOT, 13-14psi cruising and 15 at idle, so I don't think its a fuel issue. The VP is about 6 months old. Now after cruising around for 10min checking fuel pressures, I get home shut it down, try to fire it up again, won't go, starter just clicks. I'm reading 12.75 Volts on both batteries, this should be enough to turn over shouldn't it?
Sorry for the long winded post, just wanted to get some background info in.

 

so it cranks, but will not start?

or it just clicks when it's hot?

 

Sounds like your starter is beginning to go.

 

It was cranking and not starting yesterday, I spent 5 minutes cranking off and on till the battery died with not even a hint of starting. Then today after a 10 min drive, I turned it off, then tried to start it again, it cranked for about 3 seconds then seems like a dead battery, (starter just clicks) yet there is 12.75 volts at the batteries.

 

are you checking batteries with a volt meter or a battery tester?

 

Volt meter.

 

Did you spray a bunch of water around the engine bay when you washed the truck and cleaned the battery terminals.

 

Yes, i rinsed the batteries off with water.

 

I don't know where your ECM is located but there's always the possibility you got water into the ECM plug or some of your relays. Also check the crank sensor and wire all the way from the sensor, over the engine to the harness. I'm betting on ECM and relays though.

 

I'm going to check a bunch of wires, and check my grounds and hope for the best. I can't see the water being a problem though because I have powerwashed the engine a few times before and have never had any issues, this was just a quick rinse around the batteries. Its also been almost a week since there was any water under the hood, that should've dried up by now.

 

Gremlins like water! Since you moved the battery cables around, definitely check them for corroded wires at the terminals and check your engine ground.

 

having 12+ volts at the batteries doesn't mean anything, you have to check the voltage while cranking. you need amps not volts.

 

Tahnks, I've got the starter out now, and it seems faulty testing it on the bench, sometimes it needs a whack from the old ball peen. I going to pull it apart now and replace the contacts and brushes.