Brakes (lost power assist, no warning light)

[F350camper]

Hey guys, on my way to work this morning my brakes lost power assist. I have no warning light on the dash. Any ideas on the best way to troubleshoot this thing? I was thinking I would disconnect the vacuum hose at the booster and see if I have vacuum there. The truck has the serp belt setup, and the belt is fine. The vacuum pump is turning fine.

 

[argve]

Sounds like you lost vacuum - but in that case the brake light should have come on but it might be that the electrical connections are corroded or such on the vacuum sensor which caused it not to flip on the light... (just a thought)... The Enterprise would do what your describing when the vacuum pump started to go out then if I let it go long enough it would finally start to flip on the light...

 

[F350camper]

hmmm, well what ever it is I hope its totally broke so Im not trying to figure it out for days. I can say that I have totally lost power assist, and it hasnt come back so far. (about 5 miles of driving) I guess I'll disconnect the vacuum hose and see if the light comes on. Then go from there.

 

[yARIC008]

Does your air conditioning switch settings? Sounds like vacuum to me. My little vacuum sensor is just rusted to crap so when i lost vacuum i got no lights. Could be the same situation. I could tell real easy what happen to me, my vacuum pump was dangling by the belt...

 

[F350camper]

Does your air conditioning switch settings?

That was such a good idea I just ran out to check. Yes, all vacuum vent functions are working properly.

 

[F350camper]

Ok, I disconnected the vacuum hose at the brake booster, check valve and all. Hardly any vacuum getting to the booster. Also, after doing this the vents no longer switch between modes. There must have been enough vacuum in the system to operate dinky vents, but that all escaped after removing the hose.

I’ll disconnect it right at the pump and check there for good measure (far to greasy to do this in the work parking lot), but it looks like I’ll be buying a pump.

 

[argve]

also check the condition of your hoses if you have good suction at the pump...

 

[Exekiel69]

Hey Rob you can bring it or I can go check it with You, I have a vacuum gauge. Also Autozone is the cheapest I know for VP around here I think $69.

 

[F350camper]

finished vac pump swap
the truck can now stop
not too much cash to drop
I even had time after to drink a pop

 

[argve]

Cool... glad to hear you can bring her to a whoa now... Yep it is a pretty easy quick repair...

 

[Russ]

finished vac pump swap
the truck can now stop
not too much cash to drop
I even had time after to drink a pop

Rob please STOP
(no pun intended)

 

[F350camper]

Rob please STOP
(no pun intended)

are you saying my thread is a flop?
The truck still runs like a top.
and I couldnt even do the work in my shop.

 

[tuckerd1]

are you saying my thread is a flop?
The truck still runs like a top.
and I couldnt even do the work in my shop.

What is this Dr Seuss time!!

 

[jeffgordon24]

you dont need as much vaccum for accesories as brakes you can check with a guage at the booster . usually if you start the truck and press the brakes the firstt shot is ok and goes down hill from there if it is the pump
check also for pierced vaccum lines i change mine recently and didnt look old the old one . change alot at work too

 

[Darrin Tosh]

finished vac pump swap
the truck can now stop
not too much cash to drop
I even had time after to drink a pop

Made ME laugh,.. good one Rob.