need help identifying a sensor
Thread Starter
|
New User
Joined: Dec 2011
Posts: 4
Likes: 0
need help identifying a sensor
I have an 84 f250 w/6.9l.The truck won't start.The glow plug light was not comeing on so I checked the system and found a blowed inline fuse(looks like someone replaced a fuse link with an inline bar fuse)anyway i tried to replace the fuse and it blowed as soon as i turned the switch on.The fuse is feedind to the gp controller and what looks like a temp send unit on the front passenger side of the motor screwed into the intake right behind the radiator hose inlet.It has two prongs on it.When i unplug it the fuse stops blowing and my glow plug light coms on.Does anyone know what this sensor or whatever is and what it does?
Senior User
Joined: Jan 2007
Posts: 298
Likes: 1
From: Mexico
This is just my experience. When my sensor came undone, my glow plugs would only cycle for 5 seconds. When I re-attached it my plugs cycled for 10 seconds. It must have something to do with the glow plug system.
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
I know on the 86 down system it has nothing to do with, the glowplugs, and I don't see how it could have anything to do with the later system. It is a switch that gives power to the cold start advance and and the fast idle solenoid until the water temp is 112 degrees.
So it is either on or off at 112, I don't see how it could affect gp times. The controller for his 84 is on the very back driver side of the engine.
So it is either on or off at 112, I don't see how it could affect gp times. The controller for his 84 is on the very back driver side of the engine.
Trending Topics
Logistics Pro
Joined: Sep 2010
Posts: 4,411
Likes: 4
From: Victor, MT
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
Cross-Country
Joined: Dec 2011
Posts: 72
Likes: 0
From: St. Francois Co. Missouri
Is the wires that the fuse holder is connected to a red wire with a light green stripe? If it is, according to my schematic, that wire comes from the ignition switch (or a relay powered by it), through the fuse (what used to be a fusible link), and it feeds the GP controller its ignition input along with the fuel heater, paralleled off of that to the fuel cutoff on the injector pump, paralleled off of that to the engine temp switch you mentioned, through it to the cold fast idle and cold advance solenoid on the injector pump. Is by chance the fuse too small? Someone might have put that fuse in the summer time, and now that it's getting colder outside, it's got extra current through it because of the fuel heater. Actually, according to my schematic for your truck, unless the wiring has been modified from how it came factory, if that fuse blows the truck shouldn't even run because it's also the power circuit to everything on the IP.
Last edited by jb10725; Dec 5, 2011 at 07:37 PM. Reason: Inserted more info.
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
I don't know how much juice the fuel heater uses, but I don't think it varies with the temps. I'm not even sure I have ever owned one that worked, as no bigger than they are there is no way they can heat the fuel as fast as it is burned, to me they are basically on there for looks.
Fleet Owner
Joined: Jul 2006
Posts: 20,376
Likes: 843
From: Mi'kma'ki
its not meant to heat the fuel,just meant to keep the fuel filter warm so that doesn't plug up from gelled fuel in winter months.
iv had it happen once.diesel 911 took care of it though.
it was however a real nasty water filled batch of fuel.
fuel heater inop on mine too.
now iv got a coolant filter right next to it,so iv got to wrap the two filters together.that should work better than the little stock expensive fuel heater anyway.haven't gotten around to this yet lol.but i do have some 911 in the toolbox now.
(which works super fast just poured into the tank with the e-pump running fyi.10 mins she was back in action.could of just done road side had i known.)
iv had it happen once.diesel 911 took care of it though.
it was however a real nasty water filled batch of fuel.
fuel heater inop on mine too.
now iv got a coolant filter right next to it,so iv got to wrap the two filters together.that should work better than the little stock expensive fuel heater anyway.haven't gotten around to this yet lol.but i do have some 911 in the toolbox now.
(which works super fast just poured into the tank with the e-pump running fyi.10 mins she was back in action.could of just done road side had i known.)
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
They gel worse when they are parked, the returning fuel actually helps with that.
If they do gel when they are dead I don't see that the fuel heater is going to help anything, as the fuel in the ip, the inj. lines and injectors is the problem with starting .
If they do gel when they are dead I don't see that the fuel heater is going to help anything, as the fuel in the ip, the inj. lines and injectors is the problem with starting .
Cross-Country
Joined: Dec 2011
Posts: 72
Likes: 0
From: St. Francois Co. Missouri
I got curious and checked the current draw of the fuel heater on my truck this morning. When it was on, and the glow plugs on at the same time, truck not running, it was drawing about 3 amps. If the glow plugs weren't cycling or the truck was running, it probably would have been slightly more since the voltage would have been slightly higher. The fuel heater has it's own internal temperatue switch that closes at about 30 degrees F. That's why I was wondering what size fuse the OP was using. I guess there is also the possibility of a shorted to ground temperatue sensor or wire, or even the possibility of an internally shorted fast idle or cold timing advance solenoid blowing the fuse. I don't know how effective these heaters are anyway, but I guess they can't hurt.