cruise control only working partially, vents only work on floor/defrost. Vacuum??
 

my cruise only kinda works. i set it and it will sort of try to maintain speed, but it is very slow to adapt and maintains speed far below where i set it to. also i can only get defrost and floor out of my hvac. i see that there appears to be an electric vacuum pump on the inside of the left fender in addition to the mechanical one on the accesory drive. also the brake warning light is on.

the brake booster is working and brakes feel fine so i do have vacuum, i know some of the powerstrokes would turn the brake warning light on if they had vacuum pump issues.

anyone have any ideas how to troubleshoot the system?

the truck has had these issues since i bought it. for some reason it passed two safety inspections with the brake warning light on (I got hosed)

thanks

My truck had the same problems. All of those are vacuum related. Your ABS light is probably on too?

But check all of your vacuum hoses running all along the firewall and down to the vacuum pump before you replace the pump itself. Some lines might be snapped in half or simply one of the connections popped off or came loose.

If you find that one of the plastic lines snapped just get a piece of rubber hose to patch up the break. I used an old windshield wiper hose I found laying in the garage.

Good luck!!


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1995 Dodge Ram 3500 Dually 4WD | 4" straight pipe to 9" Stack | Cold air intake | 18* Timing | Tuned AFC w/ stock Fuel Plate

X2 on the vacuum lines on the fire wall

yup abs light is on. i figured the previous owner disconnected it as the fuse and relay were not in the PDM under the hood. there wasnt even any terminals in the fuse block so maby thats only for a gasser or 1500 or something. i was going to try to get the little electric pump from wreckers when i had to build a frankenstarter, (motor and gears from my starter (rebuilt by nitwits or dropped by a mechanic) and gearcase/solenoid from junker starter as the start terminal was loose in solenoid :rocking:) but they only had a 24v with hydraboost and it didnt have one. i will check the lines out first. i looked them over and they looked ok but i didnt look very hard, so they may have a crack i didnt see.

thanks!

Hopefully it's just a line :)

No problem.


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1995 Dodge Ram 3500 Dually 4WD | 4" straight pipe to 9" Stack | Cold air intake | 18* Timing | Tuned AFC w/ stock Fuel Plate

i had a truck that the defrost only works same with my current truck with the cruise too mine doesnt work. its all vacuum if only they could make it all electrical im good with that stuff:argh: