CAPS diagnosis

[Bjorkinman]

So I posted about ISC 250 concerns recently because I’m looking at buying a 2000 Thomas pusher with the 8.3.
My question now is how do I determine whether the CAPS pump on this bus is good or not? When I test drove it, it died once and seemed to have a lack of power at times with a sporadic check engine light. I think the issue is fuel related but if the CAPS is bad I don’t even want to go down this rabbit hole. If I could determine that the CAPS is okay, I wouldn’t mind buying this and putting on a fass or air dog (another thread for conversation) to remedy the lift pump issues. Any help is appreciated. I believe the pump on this engine is the VP44 correct?

[TJones]

You could replace the fuel filters and see if the engine runs well. If it still stalls and looses power with new filters it could be that the CAPs is bad. If you got the error code off the computer it would give you a good idea of what was going on.

Ted

[fo4imtippin]

The isc does not have a vp44. The 6CT had a Bosch p7100 pump and then the ISC went to CAPS system which is much more expensive. There's actually a lot more info on troubleshooting them in RV forums as they were commonly used there.