Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Engine quits in the run position

Thread Tools
 
Search this Thread
 
Old Apr 20, 2013 | 06:09 PM
  #1  
sgtrwg's Avatar
sgtrwg
Thread Starter
|
Senior User
Joined: Jul 2004
Posts: 216
Likes: 0
From: North Branch, MI
Engine quits in the run position

My truck starts just fine but as soon as I release the key to the run position it quits. I'm guessing that the ignition run circuit has a break somewhere but I have no idea which wire I should check. Does anyone have a wiring diagram that shows which wire would be suspect? I have looked at several diagrams on the internet but I have no idea which wire I should be checking. It's a 78 F150 Custom with a 302 4 speed trans.

Thanks in advance for the help..

Bob G
 
Reply
Old Apr 20, 2013 | 07:01 PM
  #2  
montana_highboy's Avatar
montana_highboy
Post Fiend
Joined: Apr 2008
Posts: 8,261
Likes: 15
From: Big Sky Country
It's either the ignition switch itself or the resistor wire that's at fault.

Check the three wire plug about midway on the firewall, it will have a white wire w/red stripe, red wire w/white stripe and a red wire w/green stripe.

With the ignition switch in the "RUN" position check for voltage at the red wire w/green stripe.
 
Reply
Old Apr 21, 2013 | 07:46 AM
  #3  
jim collins's Avatar
jim collins
Cargo Master
Joined: Apr 2009
Posts: 3,038
Likes: 4
From: South west Idaho
Club FTE Silver Member

The resistor wire under the dash was my problem once, just cut it out and splice in a new one.

I agree a bad ignition switch can do that too.
 
Reply
Old Apr 21, 2013 | 09:06 AM
  #4  
fasthauler's Avatar
fasthauler
Fleet Mechanic
20 Year Member
Joined: Mar 2004
Posts: 1,398
Likes: 17
From: Hesperia, CA
Club FTE Gold Member
Here is a simple diagram that has been posted before on the DuraSpark. It should help you understand what is going on.
 
Attached Images  
Reply
Old Apr 21, 2013 | 10:53 AM
  #5  
sgtrwg's Avatar
sgtrwg
Thread Starter
|
Senior User
Joined: Jul 2004
Posts: 216
Likes: 0
From: North Branch, MI
Thanks, it looks like the weather this afternoon will be good enough to dive into this and find the problem once and for all.

"The resistor wire under the dash was my problem once, just cut it out and splice in a new one." Jim, is this going to be the red wire with the green stripe or is it some other color?

Again thanks for the info.

Bob G
 
Reply
Old Apr 24, 2013 | 02:21 PM
  #6  
sgtrwg's Avatar
sgtrwg
Thread Starter
|
Senior User
Joined: Jul 2004
Posts: 216
Likes: 0
From: North Branch, MI
Well, I got it running this afternoon even with the rotten weather. The parts came in the mail this morning and the first thing I did after lunch was to change out the switch and viola it started and stayed running with the switch in the run position.

Now to pull the carb and to through it, the accelerator pump is leaking, and the old girl should be back in running condition once again.

Thanks again for your help....

Bob G
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
RandyP63
1967 - 1972 F-100 & Larger F-Series Trucks
6
May 2, 2016 11:55 PM
youngone1234
1967 - 1972 F-100 & Larger F-Series Trucks
13
May 1, 2016 04:11 PM
dgrant09
Electrical Systems/Wiring
2
Mar 16, 2008 11:44 AM
onestep
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
3
May 20, 2002 07:37 AM
hartmark
1973 - 1979 F-100 & Larger F-Series Trucks
5
Jan 3, 2002 09:05 AM




All times are GMT -5. The time now is 05:19 AM.

story-0
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-02 21:45:57


VIEW MORE
story-1
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-05-30 18:33:59


VIEW MORE
story-2
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-3
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-4
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-5
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-6
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-7
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-8
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-9
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE