Notices
1994.5 - 1997 7.3L Power Stroke Diesel  

Intermittent Rough, need troubleshooting help

Thread Tools
 
Search this Thread
 
Old Apr 19, 2017 | 02:25 PM
  #1  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Intermittent Rough, need troubleshooting help

Hi everyone!

My ride:
1994 Ford 350 XLT dully 7.3 turbo. 180k miles

I've done a lot of reading on this "intermittent rough running idle problem" and I need to troubleshoot to see if I need to open my valve covers.

I found this thread: https://www.ford-trucks.com/forums/8...ck-shakes.html

The thing is my truck has 2 - 5 prong connectors on each valve cover and I'd like some help ohm-ing this out seeing if I have an open or short some where.

I also found this:



Seems like I don't have a common ground....

Can someone help me with what steps to take on finding out if I have a bad injector, glow plug, and or open.

Thanks for your time!
 
Reply
Old Apr 19, 2017 | 02:47 PM
  #2  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
I like to use this from the IDM connector


Common ground for GPs is the engine.


110 to 140 is supplied to injectors via middle connector and grounded by PCM to fire


 
Reply
Old Apr 19, 2017 | 02:55 PM
  #3  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Nice, thanks! I'll give this test a shot.

About where is the IDM connector located on this engine?
 
Reply
Old Apr 19, 2017 | 03:13 PM
  #4  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
right behind the air cleaner near the fuse box is the IDM next to fender
 
Reply
Old Apr 19, 2017 | 05:17 PM
  #5  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Hi Knottyrope,

I check this when the engine was cool.

Results:

Test 1: good, pin 24&21 was 3.6-3.7 ohms
Test 2: Good
Test 3: Good

This is what I was afraid of......So now what??

-Rob
 
Reply
Old Apr 20, 2017 | 08:22 AM
  #6  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Sorry I gotta bump this......

Does anyone else recommend any further troubleshooting before I just bring it to a shop?

I will add, temperatures been dropping at night past few days, last night it probly got to ~35F, when starting it this morning it was smoking pretty good....once the engine is warmed up enough smoke is mostly gone.

Thanks.
 
Reply
Old Apr 20, 2017 | 12:40 PM
  #7  
jacob_powerhouse's Avatar
jacob_powerhouse
Senior User
Joined: Nov 2009
Posts: 199
Likes: 0
From: Kendallville
subscribed.
 
Reply
Old Apr 20, 2017 | 01:03 PM
  #8  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
rougher when cold could be a bad Glow plug, did you ohm them out too?


Remove connecter at valve cover and measure from outer pin to gnd.


How many mile? mine smokes a lot when cold but I know its injector Armature clearance that is retarding my timing and possibly the oil return isn't big enough on the injector making cold starts harder.


I just bought this shim kit to install next week along with new GPs and GPR
94-03 7.3 POWERSTROKE injector tune up shim KIT w/ special Tools to install
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-2

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-3

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-6

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old Apr 20, 2017 | 04:03 PM
  #9  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Think I found the problem

Knotty: 185k miles

I went to check the glow plug, pull the connector off the passenger bank front and it's covered in oil and the connector looks burnt....
this is the forward connector front:
Passenger front
Close up on passenger forward connector
and this is the passenger rear connector, it's got the pin but peace of the corrector broke....



Drivers front, Connector looks fine but covered in oil....





Here is another kind of side subject but I was doing some reading and wondering if my o rings for injectors were going, so I dumped the bi-pass from the fuel filter bowl and collected it......Idk what to say about it.....it really has no smell and kinda gel like......anything to be concerned with?






So what is a corrective action here? Do I have to buy a whole new harness? Where to buy? I'll get some contact cleaner and still try to ohm out the plugs... thanks so far on the right track!
 
Reply
Old Apr 20, 2017 | 05:08 PM
  #10  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Okay, I did some research.....I ordered 2 new Dorman valve cover gaskets that have the harnesses integrated into the gasket, each valve gasket comes with 2 "pig tail" connectors.

Also ordered 8 new glow plugs, Brand: Motorcraft.........motorcraft is a good brand right?

I'll keep everyone up-to-date.
 
Reply
Old Apr 20, 2017 | 07:04 PM
  #11  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
Originally Posted by Rob_Diesel
Okay, I did some research.....I ordered 2 new Dorman valve cover gaskets that have the harnesses integrated into the gasket, each valve gasket comes with 2 "pig tail" connectors.

Also ordered 8 new glow plugs, Brand: Motorcraft.........motorcraft is a good brand right?

I'll keep everyone up-to-date.
ZD11 I hope you bought

I just bought some today and a new stanco GPR
 
Reply
Old Apr 20, 2017 | 08:27 PM
  #12  
Rob_Diesel's Avatar
Rob_Diesel
Thread Starter
|
Junior User
Joined: Apr 2017
Posts: 58
Likes: 0
Originally Posted by knottyrope
ZD11 I hope you bought

I just bought some today and a new stanco GPR
yes sir ZD11.....eight of them....you've had good results?

Lol what a GPR?? All these acronyms are driving me crazy lol.
 
Reply
Old Apr 20, 2017 | 10:10 PM
  #13  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
Originally Posted by Rob_Diesel
yes sir ZD11.....eight of them....you've had good results?

Lol what a GPR?? All these acronyms are driving me crazy lol.
There is a sticky on top with tons of info. Learning this thing helps to know what's going on. I have learned a ton in here. Lots of good guys here too.

Glow Plug Relay
 
Reply
Old Apr 21, 2017 | 06:39 AM
  #14  
MI02SVT's Avatar
MI02SVT
Senior User
Joined: Dec 2014
Posts: 348
Likes: 0
I had an intermittent problem with mine a while ago everything looked good

for some reason I decided to pull pins out of the valve cover harness and found one pin had broken off inside and would break contact sometimes

Bought a new plug and replaced the wire and pin and was fine
 
Reply
Old Apr 21, 2017 | 08:37 AM
  #15  
knottyrope's Avatar
knottyrope
Lead Driver
10 Year Member
Photogenic
Shutterbug
Loved
Joined: Apr 2016
Posts: 7,182
Likes: 1,337
From: Bahstun
your fuel looks fine, what does the fuel filter look like?
 
Reply



All times are GMT -5. The time now is 05:31 PM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

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


VIEW MORE
story-1
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-2
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-3
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-4
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-5
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
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE