Notices
Pre-Power Stroke Diesel (7.3L IDI & 6.9L) Diesel Topics Only

Unidentified plug in engine harness.

Thread Tools
 
Search this Thread
 
Old Feb 19, 2024 | 10:25 PM
  #1  
Firs's Avatar
Firs
Thread Starter
|
Mountain Pass
Joined: Jan 2023
Posts: 144
Likes: 11
Unidentified plug in engine harness.

Hey, can someone please help me out and identify this plug on my 1993 7.3 idi? It is in the section of harness with the three plugs for the ip and the relay for the water in fuel light. Thank!


 
Reply
Old Feb 20, 2024 | 06:26 AM
  #2  
tjc transport's Avatar
tjc transport
i ain't rite
Joined: Mar 2005
Posts: 65,607
Likes: 5,629
From: Marlboro Mental Hospital.
Club FTE Gold Member
is your fast idle and timing advance working?
there is a sensor next to the thermostat housing, sorta under the alternator that tends to get unplugged when alternator is changed.
look straight down between alternator and t-stat housing and you will see it...i dont remember if it is one wire plug or two wire plug.
 
Reply
Old Feb 20, 2024 | 07:36 AM
  #3  
Firs's Avatar
Firs
Thread Starter
|
Mountain Pass
Joined: Jan 2023
Posts: 144
Likes: 11
Sure is a two prong deal down there. Now how do I know which way to orient the connector, and what does the little guy down there do?
 
Reply
Old Feb 20, 2024 | 07:56 AM
  #4  
gespeter's Avatar
gespeter
Mountain Pass
Photogenic
Joined: Oct 2021
Posts: 222
Likes: 60
That's the temp switch and it's basically a simple N/C (Normally Closed) when the engine is cold.
Shouldn't matter which way the plug goes on.
I have noticed some have one copper colored and one brass colored terminal, however. Not finding any reference as to why the colors, I just hook the one that has +12 to the copper one, and the lead that goes to fast idle + advance to the brass one.
BTW the fast idle solenoid isn't strong enough to actually "push" the throttle up, only strong enough to hold it up. So you must push pedal down a bit before cold starting to set it. It will stay up by itself until the aforementioned switch opens and will drop back by itself when engine begins to warm up.
 
Reply
Old Feb 20, 2024 | 08:04 AM
  #5  
Firs's Avatar
Firs
Thread Starter
|
Mountain Pass
Joined: Jan 2023
Posts: 144
Likes: 11
Thank you two for the info. I’m new to my idi and trying to understand it more. Now what about this CTA thing? Is it easy to test? I’m wondering if mine is not working as when I do a cold start: it starts up really well, but has a miss and spews white smoke for about 30 seconds, then it kicks down to a smooth idle.
I'm not sure if it’s related, but I also have determined that my IP is very retarded with my white smoke at idle, down on power, smoky when accelerating, and difficulty to get up to temperature.
 
Reply
Old Feb 20, 2024 | 09:58 AM
  #6  
tjc transport's Avatar
tjc transport
i ain't rite
Joined: Mar 2005
Posts: 65,607
Likes: 5,629
From: Marlboro Mental Hospital.
Club FTE Gold Member
if that temp sensor is not connected, the timing will be retarded when cold.
hook it up and it should stay high idle for a lot longer, and the smoke should go away almost instantly.
 
Reply
Old Feb 20, 2024 | 10:21 AM
  #7  
Firs's Avatar
Firs
Thread Starter
|
Mountain Pass
Joined: Jan 2023
Posts: 144
Likes: 11
Got it wired up and sure does work! Thanks to y’all!
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Robert'92
1987 - 1996 F150 & Larger F-Series Trucks
3
Nov 2, 2021 06:21 PM
Douglas Hauptmann
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
20
Mar 13, 2021 03:06 AM
borffmann
1987 - 1996 F150 & Larger F-Series Trucks
8
Dec 1, 2019 04:57 PM
bashby
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
8
Oct 24, 2010 07:39 AM
projectbad78
1973 - 1979 F-100 & Larger F-Series Trucks
11
Jul 4, 2008 11:52 AM




All times are GMT -5. The time now is 02:25 AM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic 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 | 2026-06-03 11:38:36


VIEW MORE