Notices
1999 - 2003 7.3L Power Stroke Diesel  
Sponsored by:
Sponsored by: DP Tuner

Rough Idle

Thread Tools
 
Search this Thread
 
Old Nov 23, 2008 | 05:28 PM
  #1  
Eric326's Avatar
Eric326
Thread Starter
|
Junior User
Joined: Oct 2007
Posts: 68
Likes: 0
Rough Idle

Hey everyone,

Hopefully someone can agree, I am trying to help a buddy with his 7.3L. The current problem is that it is idling extremely rough, to the point that it will die unless you give it throttle. If the engine is revved over 2k RPM then it will smoothe itself out quite a bit. But the minute it falls down again it will idle rough. I personally feel that this problem is probably the ICP from what most people describe. I have unplugged the ICP to test, but it usually still runs rough. Although one of the times it was unplugged and the engine actually idled normal. Ok, here is another strange clue that might give someone a hint. While idling rough, if the drain valve on the fuel filter is opened the engine smoothes right out and runs as if nothing was wrong. That one kind of stumped me, but then again I never owned a 7.3L. Thanks for the input everyone.
 
Reply
Old Nov 23, 2008 | 05:34 PM
  #2  
F350-6's Avatar
F350-6
Post Fiend
Joined: Mar 2007
Posts: 26,966
Likes: 50
From: Texas
What kind of mods have been done to the 7.3? If the FPR has been shimmed too much, the fuel pressure may be too high and causing the idle issue.
 
Reply
Old Nov 23, 2008 | 05:39 PM
  #3  
Eric326's Avatar
Eric326
Thread Starter
|
Junior User
Joined: Oct 2007
Posts: 68
Likes: 0
Hhhmm, I wondered if that might have been an issue. Do the 7.3's have an easy fuel pressure test port? And yeah I know he has had it modded atleast a fair amount since it has an aftermarket larger turbo and banks six shooter chip on it.
 
Reply
Old Nov 23, 2008 | 05:45 PM
  #4  
F350-6's Avatar
F350-6
Post Fiend
Joined: Mar 2007
Posts: 26,966
Likes: 50
From: Texas
You can remove a plug on the back of the fuel filter bowl and place a gauge there. The shim is put in the FPR (fuel pressure regulator) on the side of the fuel filter bowl. He could probably remove the shim as fast as you could install a gauge for test purposes.
 
Reply
Old Nov 23, 2008 | 06:00 PM
  #5  
Steve_250's Avatar
Steve_250
Posting Guru
Joined: Nov 2003
Posts: 1,949
Likes: 0
From: Near DC
And it could be the famous CPS!
 
Reply
Old Nov 24, 2008 | 11:43 AM
  #6  
Eric326's Avatar
Eric326
Thread Starter
|
Junior User
Joined: Oct 2007
Posts: 68
Likes: 0
Sorry, just as a tid bit of information I must add that he has already replaced his CAM sensor.
 
Reply
Old Nov 24, 2008 | 02:55 PM
  #7  
Action4478's Avatar
Action4478
Hotshot
Joined: Aug 2006
Posts: 10,764
Likes: 39
While you have the FPR apart ,,clean it ,,My wag is trapped air ,,..have seen it blow fuel lids before ...
 
Reply
Old Nov 24, 2008 | 05:46 PM
  #8  
GrizzlyPiet's Avatar
GrizzlyPiet
Junior User
Joined: Oct 2008
Posts: 76
Likes: 0
From: Killeen / Ft Hood, TX
FWIW - Mine did almost the exact same thing. It would idle really bad up to about 2000rpm then smooth out, I had a dead injector.
See this thread - https://www.ford-trucks.com/forums/7...ml#post6688276
Hope this helps
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-1

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-2

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-3

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-4

Every 2026 Ford Engine Explained

 Brett Foote
story-5

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-6

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-7

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-8

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-9

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote




All times are GMT -5. The time now is 09:13 PM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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-7
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
story-8
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-9
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