low idle
05-24-2015, 10:01 PM
#1
Registered User
Thread Starter
low idle
Hey guys im not sure but my truck seems to idle low when it gets hot .....i turned the idle screw up now it seems like its doing it again....
05-24-2015, 10:21 PM
#2
Registered User
Join Date: Sep 2014
Posts: 138
Likes: 0
Received 0 Likes
on
0 Posts
Had a 6.2 that after running and getting shut down would not restart until allowed to cool. We trouble shot this issue for the better part of a year, replaced shutoff sole kids etc. turns out the issue was to small of a wire running the fss.
If I was you I would make sure your fss wiring is in good shape. I would also check and make sure the fss itself is in good shape.
Are you sure you're idle screw and max fuel screw are locked down tightly? Both coul potentially back out over time this reducing idle speed.
I'm assuming your filleter maintenance etc is up to date.
If I was you I would make sure your fss wiring is in good shape. I would also check and make sure the fss itself is in good shape.
Are you sure you're idle screw and max fuel screw are locked down tightly? Both coul potentially back out over time this reducing idle speed.
I'm assuming your filleter maintenance etc is up to date.
05-25-2015, 12:08 AM
#4
Registered User
Join Date: Jul 2010
Location: Napa, CA
Posts: 131
Likes: 0
Received 0 Likes
on
0 Posts
In my experience a low idle when hot is generally due to the injection pump on its way out. Try turning up the full power screw, you might find that it helps the condition.
05-26-2015, 08:49 PM
#6
Anyone got a good closeup pic of the FSS and its wire? My shop manual is 4 hrs away. Thnx in advance
05-26-2015, 10:20 PM
#7
Registered User
To check injection pump health pour cold water on the injection pump when the idle drops and see if the idle increases, if it does it could mean a new pump is in your future. Another thing to check is the idle screw, mine vibrated loose and the idle was all over the place. Hope it's an easy fix. Good Luck.
Trending Topics
05-26-2015, 10:57 PM
#8
Registered User
The FSS is circled, usually has a ring terminal to attach it to the stud
05-27-2015, 05:28 AM
#9
Thnx gyman 98
05-27-2015, 04:10 PM
#11
Registered User
This..... I drove mine like that for a while till it started to leak. Got it rebuilt and all was good after that.
05-27-2015, 05:54 PM
#12
Registered User
It should be about 12.5-13.5 volts without the truck running and 13-14.5 running
05-29-2015, 12:32 PM
#13
Registered User
To check injection pump health pour cold water on the injection pump when the idle drops and see if the idle increases, if it does it could mean a new pump is in your future. Another thing to check is the idle screw, mine vibrated loose and the idle was all over the place. Hope it's an easy fix. Good Luck.
05-29-2015, 01:06 PM
#14
Registered User
Failure is due to wear in the high pressure pumping parts. Cold increases the viscosity of the fuel, decreasing the leakage and increasing pressure.
It's not a fix, but a diagnostic.
We used to diagnose vapor lock in gassers (back in the 60's) by cooling the fuel pump. A half a grapefruit jammed down on the fuel pump would get you 100 miles down the road in hot weather.
It's not a fix, but a diagnostic.
We used to diagnose vapor lock in gassers (back in the 60's) by cooling the fuel pump. A half a grapefruit jammed down on the fuel pump would get you 100 miles down the road in hot weather.