The Diesel Garage banner

1 - 6 of 6 Posts

·
Junior Member
Joined
·
42 Posts
Discussion Starter #1
got a 1990 f250 automatic with a 7.3 in it i drove it fine last night and parked it and this morning it wont start i put a new glow plug relay on it and still nothing glow plugs checked out good so my 2 questions are when i put the new relay on it u have 2 big post and 2 lil posts what is the wiring diagram for that and where is the fuel pump located @ on the block and how do i check the fuel pump to see iff its working
 

·
TDG MAFIA
Joined
·
730 Posts
Have you checked the glow plugs with a test light? Take a test light hook it to the positive and touch the tip of each glow plug but they must be unplugged. If the test light lights up you verify there working, make sure all 8 work.

You either have a glow plug or a fuel problem, thats the only problems it could be.

does the wait to start light stay on about 10 seconds?

I dunno the wiring diagram for the relay off the top of my head..

The fuel pump is located on the passenger side of the motor up front, a little below the fuel filter. While your cranking have a buddy push in the schrader valve on the side of the filter housing and see if its getting fuel.
 

·
Super Moderator
Joined
·
4,247 Posts
The GP is controlled by the GPC (Glow Plug Controller) that it is mounted to.

With the "WTS" light ON, you measure from one large terminal to the other with your DMM and if you get more than 1V, the GPR is bad. Aftermarket GPRs are notorious for low quality.

As others have indicated, you need to have good GPs first. Take a test light, connect it to Battery POS (Alt +, Bat + etc) then touch the tip of each GP, the test light MUST light brightly - BTW DO NOT use an LED test light!!!!!!! Use one with a regular bulb or even another light using a 194 type bulb will work.

You might have failed the fusable link to the GPR, it is 20 years old, that would result in no B+ to either large terminal on the GPR.
 

·
Member
Joined
·
68 Posts
a quick way to verify a glow plug issue is to plug the block heater in for a bit. if it starts easy after being plugged in, then it would be an issue with either the glow plugs or controller. if not, it would be fuel. while cranking, is there smoke coming out of the tail pipe?
 

·
7.3 addict
Joined
·
644 Posts
did somebody mention truck will turnover with bad batteries but won't start. start by checking batteries first before changing parts.
 

·
Junior Member
Joined
·
42 Posts
Discussion Starter #6
it starts now changed out the fuel pump and glow plug relay but now my wait to start lite dont work right
 
1 - 6 of 6 Posts
Top