Community Forums

mikee409 · 04-10-2017, 05:09 PM

Any one out there had to replace the transient fuel supreser on a 2001 isc 330 . Not sure if it's in the fuel pump or outside of it.My motor man said the codes pointed him that way but he wasn't 100% sure .
He was honest and said take it to Cummins in Houston he didn't just want to throw parts at it.
Still showing a ck engine light that won't reset. The yellow upside down light bulb with exclamation point in it symbol.

Skip426 · 04-10-2017, 05:40 PM

I have a document on the Cummins fuel system on your 2001 , ISC , and quickly read through the 101 pages on the CAPS fuel system and can't see any part by the name " Transient Fuel Suppresser " I can't say that the name came up in the 4 different Cummins fuel systems I worked on in Dodge trucks with the 5.9 engines either. But I'll do a Google search and see what I can come up with , I love a mystery.

palehorse89 · 04-10-2017, 05:44 PM

Quote:

Originally Posted by Skip426

I have a document on the Cummins fuel system on your 2001 , ISC , and quickly read through the 101 pages on the CAPS fuel system and can't see any part by the name " Transient Fuel Suppresser " I can't say that the name came up in the 4 different Cummins fuel systems I worked on in Dodge trucks with the 5.9 engines either. But I'll do a Google search and see what I can come up with , I love a mystery.

I read his post Skip, but did not reply.........wondering if he is referring to the "Lift Pump" ?

Skip426 · 04-10-2017, 05:53 PM

There was a reason I didn't find the part in the document , I was looking at parts attached to the CAPS pump and the description online has the suppressor as an electronic surge guard for the ECM and it's attached to the engine wiring harness . I'll see if I can download more info and a picture , the site I was on , blocks downloads so I couldn't get it there.

mikee409 · 04-10-2017, 05:56 PM

Not the lift pump. The transient element supposedly looks at the fuel temp, engine temp, among other things and adjust the amount of fuel to the injectors I guess.

Skip426 · 04-10-2017, 06:23 PM

Quote:

Originally Posted by mikee409

Not the lift pump. The transient element supposedly looks at the fuel temp, engine temp, among other things and adjust the amount of fuel to the injectors I guess.

From the info online , the suppressor , is to protect the ECM and the electronic injectors solenoids from power surges related to the activation and de-activation of the solenoids . I have picture and diagram but can't find a location, other than a warning saying the suppressor can be hot when operating.
If the suppressor has failed and setting a code , then driving the coach any distance could damage other electronic components, and at a listed price online of $118. worth changing right away. JMHO.

mikee409 · 04-10-2017, 08:03 PM

That's what I'm afraid of, Houston is 1-1/2 hrs away. I'm going to do more engine compartment diving and hope to find it. I'll gamble the $118 be4 driving to Houston. Last time I was there 3 yrs ago it was min. $300 just to have a mechanic open the engine compartment.
It will be my luck that its inside the Capps pump somewhere.
Mike

Skip426 · 04-10-2017, 10:56 PM

Very short distance and wiring harness , between the CAPS pump and the ECM, looks like 12 to 18 inches, from this diagram , items 13 and 20. so hope it's an easy find.

EDIT: Still looking to see if someone posted a picture of the location.

Skip426 · 04-10-2017, 11:42 PM

Found a picture of a used harness , suppressor is the red circle , ECM wiring multiple connectors the yellow circle.

Still looking for a picture that show the harness on the engine.

palehorse89 · 04-11-2017, 04:29 AM

Quote:

Originally Posted by mikee409

Not the lift pump. The transient element supposedly looks at the fuel temp, engine temp, among other things and adjust the amount of fuel to the injectors I guess.

Learning something here Mike, can I assume that most all of the wiring harness have one of these for protection?
After skip posted, I remember seeing one of these being trouble shot on here years back.........My memory had forgot about it though........making a note this time.

Skip426 · 04-11-2017, 10:48 AM

Still looking for a photo of the harness on the engine that shows the suppressor , other info I've found says that some companies will void the warranty on a replacement CAPS pump if the suppressor is not replaced when the the CAPS unit is installed.

From the look of the photo of the suppressor , the install will require soldering of the wiring . I wonder why Cummins wouldn't have used a plug in connector

, getting a soldering iron to the harness, on the side of the engine, is probably going to be a real pain.

mikee409 · 04-11-2017, 12:30 PM

Last year I changed the secondary fuel filter, that was a pain to get the water sensor plugged back into. And in November the gasket to the lift pump leaked some diesel. Tightened 3, 1/4"20 bolts and the leak stopped.
That area is a mess to get to where the suppressor is most likely located. Speculating I'll have to drop the diesel filter to gain access. It's raining along the TX gulf coast right now. The RV is under a shed but I still have to cross the yard to get to the RV. After I get off work I'll remove the access paned in the bedroom and hopefully see what I'm hoping is the issue and fix it my self. Thanks to all for the pictures and part numbers. I'll update when I have new info..
Mike

Skip426 · 04-11-2017, 07:01 PM

Mike ; if you can get a photo of the suppressor in it's mounted position , I'd love to have it on file.

I have a weird obsession with this kind of thing.

slickest1 · 04-11-2017, 07:29 PM

That is really good info Skip. Cummins don't seem to be that up on their codes. When I had a problem it was the rear pumping element and nobody seemed to know what that was. Finally some tech that works with caps pumps figured it out.

I will keep this info in my file also.