Over the past year I have been upgrading my truck with new parts and a few mods. Last thing I did was replace the icp and ipr sensors. Truck has been running great. But recently over the last few days when I turn the key to start all I get is a click. After several try's the truck will start strong. At First I would wiggle the shifter and sometimes it would start after wards. The other day I put in N and it started but Im starting to thing the shifter has nothing to do with it and it was just a coincidence that started. Because sometimes after a few trys it will start with out ever touching the shifter. Now the other day we had a cool morning and I went out to start the truck and let warm up. It started fine but when I turned the defrost on it turned off I mean it just died. Started it again turned on the defrost and it died. It happened a third time. So I started let It warm up and then turned defrost on and it stayed on. You can feel/hear the power drain when the air is turned on. Also felt the power drain when we tried to roll down or up the windows. All this happens only when the vehicle is warming up. This Morning it was doing the same thing so I paid attention to the battery gauge and saw that when I would turn the key nothing would happen it would not read at all. Then when it did start the gauge did not pick up for a few seconds, meaning, it showed zero amps for a few seconds and then slowly pickup to normal about 3/4 up.

I'm thinking its an alternator issue but that's just a guess. Batteries are less than 2yrs old and starter is fairly new as well. I can't remember when I replaced the alternator. Any help would be appreciate it.

My truck is a L99 f350 with 386,000.

Thanks

Gilbert

 

Tired batteries come to mind, and/or alternator especially if you running and the extra power load kills the engine, most likely due to low voltage.

 

Look at all your cable connections, especially the grounds on the firewall and engine block.

 

Thanks, gentlemen

I have checked all the connections and all is clean and tight. Batteries are are about 2 yrs old diehards. I need to check alternator.

 

Check the batteries too. Yes, they should last a lot longer than 2 years, but one of them my be bad.

 

The power drop, intermittent starting, intermittent gauge, etc made me think loose ground. The starter itself could be going out.

An easy way to watch voltage is with one of these

You can see batt voltage before cranking, with key on, watch for glow plug draw, and see if your alt is putting out the right charge

 

Alright gentlemen, I'm getting 12 v from batteries. When truck is on I'm getting a little above 15 v. According to the u tube video on how to check alternator, my alternator is overcharging? Is that right? I really appreciate the help.

 

either alternator over charging or volt meter inaccurate.can You borrow another volt meter to confirm.

 

Oreillys checked alternator they say it passes. Is there any think else that may cause alternator to over charge? I know Oreillys could be wrong. I'm kind of stumped. Any suggestions would be appreciated?

 

What output did they see?

 

after Oriellys I went to napa they checked and said that it was reading 14.5 volts. Went home and reinstalled alternator and still got a 15.7 reading. Going to picup another meter just to make sure.

 

Just invade anyone is interested. I bought a new alternator and starter selenoid. After installing the alternator I tried to start and got the same click after a few clicks it started strong. So I start to remove the selenoid and one of the post just spins post and nut. Found my starting problem. With very little effort I was able to twist post off. A bunch of dirt/crude fell out. Replaced with a new selenoid and it's starts like new . Thanks for all the help.

 

Glad it worked out. Thanks for the solution report.