1990 d250 need help lights inside and headlights pulse all the time also the charging guage bounces all over the place can anyone tell me what could be the problem thanks

 

More than likely it is a ground problem...that was my problem. These trucks are notorious for ground problems....fix a new good quality ground it will probably fix your problem.

Tony

 

if the ground doesn't fix it it could be the volt reg, or your alt,

 

Ground the regulator case to the engine. If that doesn't fix it, head for the junkyard and grab a couple of OEM Mopar voltage regulators. They are the same on all Mopars from '70 up until EFI.

 

Maybe it's time for a new guy witnessing the grid heaters in operation for the first time?

 

OP says "all the time".

 

Sleepy doesn't say where he is, .... around here in "the frozen North" my grids are already causing some big-time meter bouncing

 

Now how did I miss that part?

 

Hey Sleepy, welcome aboard the forum! , ...if you click "UserCP" in the upper left corner you can put the particulars of your truck in your signature so you won't have to spell it out on each post. Be sure to let us know how the "pulsing" is coming along, ...

 

thanks for the suggestions i have put a new alternator and regulator on it i am going to try to ground it tommorow let you know how things turn out thanks i am in virginia

 

i put a good ground from the regulator to motor at ideling it still bounces but when i drive it hold the needle still i guess i try a mopar regulator any thing else to do thanks

 

Is your needle on your gauge bouncing or is your lights still pulsing? My needle still bounces, but the lights no longer pulse. The ground that fixed mine was simply a small ground wire from the neg batt. post to the body of the truck.

Good luck, Tony

 

What if the air temp sensor that controls the grid heater goes bad? Could test my theory by disconnecting the grid heaters and seeing if the lights stil dim. Just look in the stickey for grid heater delete

 

headlights dont pulse hardly but the dash lights pulse when ideling guage still moves some even at high speeds i read where someone recommened using a blue mopar regulator is that the one thats a constant 13.5 volts if so would that overcharge the system thanks for all the help

 

When I changed mine over from an internal to an external voltage regulator, I now have the same puilsing lights (all of them) at idle. When driving down the road it is fine. Mine is a 93. I dont mind it, but sometimes it is annoying to watch in town.