Fuel filter vacuum sensor?

[saburai]

Hi Gang!
I brought my new '90 F250 XLT home, just got back. The truck ran like it was supposed to for the 200+ miles Picked up a Craigslist cap for it on the way back. I'm a tired, happy guy!
Anyway, when I bought it last week, I noticed a bit of fuel weaping from the vacuum sensor on the fuel filter housing. When I did the PO very graciously insisted that he would take it to the shop that he uses and have it fixed. Well, it's not leaking anymore. That's because the shop removed it and replaced it with a nipple. They left the sensor wire dangling. I know next to nothing about this very cool engine, but I'm learning fast! Can someone please tell me what the function of the vacuum sensor is?
TIA Rich

 

[79jasper]

Main purpose is to tell you to change the fuel filter.

Sent from my SAMSUNG-SM-G935A using Tapatalk

 

[cpdenton]

Not really sure which one you are calling the vacuum sensor.

There are three different plugs on the filter header. Well, one is actually on the bottome of the filter and that is the water in fuel sensor.
Another comes straight out of the top towards the hood and that is the fuel heater, which is pretty pointless and most people plug them when they start leaking.

The third sensor comes out the side directly next to the Schrader valve, and that is the fuel pressure sensor. When the filter gets plugged, or you lose proper fuel I let pressure is turns on the fuel filter light on the dash.

Which one did they plug?

 

[icanfixall]

A hanging wire to any sender on the filter will not harm anything. A picture of what you are posting about sure would help everyone here to know exactly what you have. My guess is the fuel heater was removed and plugged but again. Not sure what you are posting bout.

 

[OLDBULL8]

You can't replace any fixture on the filter with a nipple and not have it flow fuel out, you must mean a pipe plug.

Is this the Vacuum switch on the far left your talking about?

 

[saburai]

You can't replace any fixture on the filter with a nipple and not have it flow fuel out, you must mean a pipe plug.

Is this the Vacuum switch on the far left your talking about?

Yes. That's the same picture I used to identify the sender. Just looked at it again, the shop put pipe plugs in both the vacuum switch port as well as the Schrader valve port. Please tell me the details of the function of both. I'm assuming that the Schrader valve is used to vent air after a filter change. The vacuum sensor turns on the dash light in the event of low fuel pressure due to a clogged filter or other catastrophic fuel pressure loss. Does it input to anything other than the dash light? Pardon my lack of attention as well as my ignorance about this engine and transmission - diesels and autos in general actually...

Many thanks
Rich

 

[icanfixall]

Thanks for the clarification to what was done. You can still run fine with these ports plugged but. Its far better to have them functioning as they were designed to function. Just find a wrecking yard that allows you to pic n pull what you want. Then either pay for it or feel you paid a cover charge to get in to look round and pocket the parts. Generally speaking you will find it very difficult purchasing small parts like this from any pic n pull yard. The people on the buy window have no idea what you are trying to buy nor can they look up that small of a part. This is why I have no problem with pocketing small parts like this. I already paid my fee to look round hoping to find what I want. Many times I did not find small parts and paid for nothing but a nice walking trip thru wrecked cars and trucks.

 

[saburai]

Thanks friend.
I'm not a stranger to pick and pull relationships
By the time I drive 45-60 minutes in each direction plus the cost of the better part of a day of my time, I'd probably be better off buying new parts. Can you please suggest a on line source for parts like this?

 

[tnmtn]

my truck is leaking around the fuel heater connection. is the plug in a threaded piece or pressed in?
I'm thinking if its threaded to plug it.

 

[BDCarrillo]

my truck is leaking around the fuel heater connection. is the plug in a threaded piece or pressed in?
I'm thinking if its threaded to plug it.

Look in the tech section for the how to. It's basically a remove, drill, tap, and plug fix.

Not nagging, but please try using google to search the forum by typing "heater plug siteilburners.net"