hey guys, i have been having a problem with the idle on my truck. when i start it up in the morning it will fire up and sit and bounce the pin in the guage around 14 volts. when i am running down the road it holds steady in the same spot. once i get up to running temp little over 1/4 on temp guage, and i pull up to a stop light the voltage drops to like 9 maybe 10 volts. the idle goes down to the point where the truck starts to shake and sound like its lopeing but as soon as i hit the gas it jumps right back up and holds. i am by no means a great mechanic so i am definatly stumped by this. this is no ac, no heat, doesent matter if sterio, or onboard air, or cb are on or off. and i really dont think its the idle or want to crank it up because then it would be super high in the morning before it gets up to running temp. could it have something to do with the star wheel or fuel screw? or even fuel pin? i havent changed anything lately but i have a bd pin (it was doing this before and after i installed it) and as far as whats been done to the screws i know the full power has not been touched. but the cap for the fuel screw is missing and i know the star wheel has been turned because it puffs white smoke at idle. any ideas? i am supposed to drive it 5 1/2 hours to boise this weekend and would really love to try to smoothen this out cus i will be pulling about 8000 pounds.

 

Sounds like you have something causing a huge power draw, like a short to ground. Dropping down to 9 or 10 volts could affect your fuel shut off solenoid, reducing fuel entering the pump. I would confirm that you are loosing voltage with a multi meter, and go from there.

 

i have a digital volt guage in my truck that is also a psi guage for my on board air those are the reading from that. i will try a volt meter just to verify that its acurate and whats the best way to check all the grounds?

 

maybe need new battery or alternator not chargeing

 

the battery is brand new and i had my altenator checked at the same time cus thats what i though the problem was. that was less then a month ago and it still does it. i will check all the grounds again just to be sure, could the star wheel being to far in or out be causing it? or even the fuel screw? should i try turning them in more one at a time and see if either or makes it better or worse? ive never heard of anybody having a problem like this

 

I too thought about an alternator intermittently charging, but the voltage shouldn't drop that low.

Start at the batteries, and work you way to the chassis, frame, cab, everywhere the grounds lead.

 

hey guess i am still having problems here. i have checked all the grounds and they are all good solid grounds i used a test light on them and ran them to power on all the ground bolts then every piece of metal that the grounded bolt was in and i always got a good solid power. i am really starting to think that it may be an engine problem. i have some white smoke at idle and i tried turning up and down the star wheel with no affects. so then i started working on the fuel screw. still seems to have no effect. my truck only smokes till the turbo catches up with it and it doesent dump a ton of smoke just enough to **** off a honda behind me with h.i.d.'s but anyways it used to be a dark black smoke cloud behind me now when i look behind me it is usually a light gray or white cloud. could this mean anything?

 

not that you havent thought of this already try the voltage regulator on the firewall and check ur fuseable links