ford 1 ton dually does not run right

[pro11]

hello, i got a 1990 ford 1 ton dually with a 460 efi engine..... The truck starts are runs fine for a little while until it gets warmed up. After a little while running the truck starts to die and wants to stall and runs rough. Also the battery goes low, and the voltage gauge bounces occasionally...... So i am thinking somthing electrical.....i had the altenator tested and they said it was sopposedly good....and i have a brand new battery. what could it be?..... need help!

[97powerstroker]

yea alternator could be dying then batts start to die then there goes your ignition.sounds right.

[CAT797]

When it starts to die, is it when you come up to a stop sign or slowing down, i.e. foot on the brake? If the battery and alternator checked ok, then I wouldn't think electrical necessarily.

Could be idle air control or vaccum leak drawing rpm's too low that could cause the battery light to come on........

[MrJohnWayne]

Does it still have a single coil and distributor? If so I would get it warm and when it starts to act up test the coil.

[2005F250]

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[pro11]

i can barely get it out of my drive way without it acting up, let alone go down the road too far.......the battery light doesnt come on just occasionally the battery tact bounces around. When it acts up its almost like its not getting gas, and runs crappy.......and if i shut it off and start it again the battery seems to get low.....

BTW: where my key goes in to the ignition the steel piece (looks like a wing nut) that fell off of the ignition and steering column.....does that matter.... or cause a electrical error...??

[2005F250]

Probably a fuel problem or maybe the inertia switch is going bad.

[DAYTONA392005]

Originally Posted by pro11

i can barely get it out of my drive way without it acting up, let alone go down the road too far.......the battery light doesnt come on just occasionally the battery tact bounces around. When it acts up its almost like its not getting gas, and runs crappy.......and if i shut it off and start it again the battery seems to get low.....

BTW: where my key goes in to the ignition the steel piece (looks like a wing nut) that fell off of the ignition and steering column.....does that matter.... or cause a electrical error...??

Have the module(mounted to the side of the dist.) checked.Could be going bad.



As far as the piece on the key tumbler....be careful...you could break the key off in the tumblers,however it should not cause any other problems.

[wonder]

Originally Posted by CAT797

When it starts to die, is it when you come up to a stop sign or slowing down, i.e. foot on the brake? If the battery and alternator checked ok, then I wouldn't think electrical necessarily.

Could be idle air control or vaccum leak drawing rpm's too low that could cause the battery light to come on........

what he said. had the same problem on my 96 f350 with a 351

[mrgrimm]

If the truck has an EGR valve that COULD be the problem. I had similar drivabilty issues with one but it was a V10 in an f350. Never even made the check engine light come on...