Hi there- 2004 International 8600 with an ISM CM870.
Has a no code low power issue- hooked up fuel pressure gauge and took down the road. When driving and it run good pressure is like 160-225. When it becomes a dog fuel pressure drops to as low as 90-100. Let truck sit pressure comes back, always have to drive for a while before it messes up. Had vac guage on suction side of pump system and vacuum stays 1-2" no matter what happens. Is the pump repairable or must I replace? Any suggestions?
Thanks
When's the last time the fuel filter was changed? Although you should get a code for that.
Filter was changed recently- had problem before and after change.
truck being that old, it may be a lot of things... things like collapsing fuel lines, sucking air, leaky injectors, trash in tanks clogging pick-up tubes once in a while then settling again,.. faulty shut-off solenoid or other fuel related component like mentioned ... a lot of things.
Have you checked the vents at the tank? Sounds simple, but I had a bee build a small nest on the vent of my driver tank, causing the passenger tank to suck down faster damn near running it dry. (I thought I was just getting phenomenal fuel mpg since my sending unit is in the driver side lol)
If you have a similar situation and the other tank vent is partially clogged, it may be creating a vacuum while driving, but slowly equalizing the pressure when the engine is shut off...
Sounds simple but I'd prolly look for simple 1st being that the truck is 16y/o
Hi all,
I have a few things to go back over- had vac gauge on intake side of pump and 1-2" of vacuum was pretty much the MAX reading (while crapping out) so I do not suspect a clog or the like.
That being said I will carefully inspect... one thing I did not consider was a weak shutoff solenoid. Not really sure of any way to test that but I will watch the voltage to it to make sure I do not have a problem with that.
Northern truck- rusty plow truck- so anything is possible. I know I am on the right track just looking for enough evidence to condemn or not condemn the fuel pump.
Swen
Could be air or pump when things get hot cool down and reseal if there's not a restriction
Hi all- update on this one.
Wanted to investigate fuel pump assembly along with shutdown solenoid. Unit was crusty/rusty (due to this being a truck with a salt/sand spreader). Once overall condition was clear (bolts frozen for solenoid and other parts looking ready to disintegrate) discussed options with customer and he decided to replace pump assembly with a REMAN unit. This unit included a new shutdown solenoid.
After multiple test drives with a gauge hooked up pressure pretty much stayed around 225-250 and low power issue is now gone.
I am not sure if was a weak solenoid or the pump itself but the pump and the solenoid were very corroded, in poor condition from a visual standpoint and obviously one of the two items was the cause of the problem.
This one appears to be FIXED.
Swen
(06-28-2020 )swenlarson Wrote: [ -> ]Hi there- 2004 International 8600 with an ISM CM870.
Has a no code low power issue- hooked up fuel pressure gauge and took down the road. When driving and it run good pressure is like 160-225. When it becomes a dog fuel pressure drops to as low as 90-100. Let truck sit pressure comes back, always have to drive for a while before it messes up. Had vac guage on suction side of pump system and vacuum stays 1-2" no matter what happens. Is the pump repairable or must I replace? Any suggestions?
Thanks
How often did it start acting up on you and what did it take to start running good again before you finally fixed the issue. I have an issue I cannot figure out.