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Rick808 · 08-08-2021, **(Subject: CM871 Not Starting )**

Ok so I have a 2011 Prostar with a ISX CM871. I picked it up in Indy and ran fine until I hit Texas. Was a little hard to start in Texas but started on its own so got it to Vegas. In Vegas it wouldn’t start on its own had to use some ether.

Now its not starting at all. It will run on ether only. I pulled both filters and replaced them they’re getting fuel.

Somewhere from the filter to engine is the problem. Primer pump is working since my filters are full.

Where can I start looking for the issue at? Could it be the fuel shutoff solenoid? Im not thinking its the fuel pump since I drove it 1900 miles and when it started it ran fine.

Also does anyone have the part number for the 2 pressure valves in the fuel pump housing? International wouldn’t give me the part number. Its #25 and #37 in the diagram fp107ga

Rawze · 08-08-2021, **(Subject: CM871 Not Starting )**

You could guess at it for a month and not figure it out unless you narrow it down properly thru proper troubleshooting methods ...

It could be something fuel related (usually is), but also could be a wiring or power issue ... or even a bad ecm.

How much fuel pressure PSI does the engine show in Insite while cranking?. That is the first place to start, as it will verify that the ECM is reading the correct pressures, the fuel system has the right pressures, and at least its trying to start the engine.

here are some similar threads...

http://rawze.com/forums/showthread.php?t...3#pid11413

Nilao · 08-08-2021, **(Subject: CM871 Not Starting )**

Yup, like rawze said, check psi while cranking. Most likely your gear pump failed.

Rick808 · 08-22-2021, **(Subject: CM871 Not Starting )**

(08-08-2021 )Rawze Wrote: You could guess at it for a month and not figure it out unless you narrow it down properly thru proper troubleshooting methods ...

It could be something fuel related (usually is), but also could be a wiring or power issue ... or even a bad ecm.

How much fuel pressure PSI does the engine show in Insite while cranking?. That is the first place to start, as it will verify that the ECM is reading the correct pressures, the fuel system has the right pressures, and at least its trying to start the engine.

here are some similar threads...

http://rawze.com/forums/showthread.php?t...3#pid11413

Finally located the problem. We tested injectors and everything ended throwing a code for low fuel pressure. We started looking at the fuel pump noticed a bolt fell out and caused a leak.

This was causing it to loose prime and when it throws the low fuel pressure code it shuts off the priming pump.

We pulled the pump replaced the gasket, put a new bolt in fires up no issues and holds prime as it should