'99 & up 7.3L Power Stroke Engine and DrivetrainDiscussion of the 99 & up 7.3L Power Stroke diesel engine and drivetrain in the 1999-Up Super Duty trucks and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 7.3L Power Stroke engine.
Hey all. I am new to this site and I have a problem with my 2002 7.3 PSD. Something is killing my batteries. I looked and listened under the hood and found an apparent vacuum leak. Behind the passenger side battery, there is what appears to be a small vacuum pump. There is one electrical plug, two regular vacuum nipples? on each side toward the rear, and two posts on the front, one white and one black. There are small vacuum hose jumpers? going from the rear nipples to each of the front posts. The black post toward the outside of the engine has a small hose going to a larger black canister in between this unit and the battery. The white post... seems to have a missing vacuum line. Or maybe it is a test port and the plug fell out?
I checked my Chilton manual and there is no mention of a vacuum system on my truck, but I don't know what else this could be. HELP!
The thing that you describe is the vacuum pump and the vacuum reservoir. It's raining outside right now so I can't go and look to verify the other connections that you mention. First of all, make sure the pump works. Pull off the line to the reservoir and turn on the key, the pump should run continuously. If it doesn't the pump is fried. The best way to troubleshoot vacuum leaks is to have a Mity-Vac and gauge. Disconnect each connection downstream from the pump and pull a vacuum, watching the gauge. If it holds, go to the next connection. Leaks show up in the strangest places. My pulse vacuum solenoid (controller for the 4x4 ESOF) developed a leak within itself, caused the pump to run all the time and wear itself out prematurely.
Incidentally, the vacuum system controls A/C damper functions and front hubs, nothing else.
2008 F-250 CrewCab XLT, 4x4, short bed, 6.4L diesel, Leer camper shell. Smooth, quiet, great performance, poor mileage!
2000 F-250, PSD, CC, 4x4, XLT interior, short bed.(wrecked in Colorado, 11/2010)
yesterday i had some electrical problems and i think i narrowed it down to my positive cable, but when i turn the key on that vaccumm pump comes on and stays on the whole time the truck is running and i was going to come on here to see what it was too but you beat me to it haha. you described it to a T. mine also has that white part that sticks out and no hose on it. i think its just a air intake for the pump but thats just a guess. im not sure if its suppose to have a hose on it, but yeah what is it for? on mine the mounts are broken off and its loud and annoying, i can hear it when the truck is running and going down the street. im going to rig up some mounts for it soon.
2000 ford f-250 turbo diesel 7.3 lariat crew cab, lifted 8" w/37x12.50 cooper tires, 4" dual after market exhaust, 4" downpipe, tymar intake, tony wildman 4 pos chip, tripple under dash gauges egt,boost,trans temp 200k and counting
1997 f250 7.3 XLT ext cab long bed 4x2 bone stock 167k and counting
My vacuum pump is also coming on when the WTS light is on and it will continue to stay on for about 2 minutes during which the truck will not start. Once it is off, it starts without hesitation. It has only been having this problem for about a month and half since winter hit. Other times, I do not hear the pump turn on at all and that is when the truck is hardest to start. Am I wrong or should the vacuum pump have nothing to do with starting? On another forum I saw someone had a similar problem and was told to check their battery terminal connections, but there was never a response as to whether or not the problem was ever resolved and I've found no signs that I've got a bad connection.