2ws starting problem

Was there a question in there? JK .....givin you crap

I would start with shaking down the wiring. Load test the powers and grounds to the ECM. Or maybe the ECM is starting to crap out. My bet is on wiring.

 

Usually ecm failures are not intermittent, once they are done thats it, they don't come back. They are reman exchange.

 

After it has been shut off for quite awhile, check to see if the alternator is warm before starting it. The alternator can charge fine while running, but will draw while shut off if it has a bad diode.
One of the easy things do begin with in the process of elimination.

 

With a 2WS, I am guessing we are talking about your username a1999 Peterbilt. When you start it or fails to start, pay attention to check engine light and tach. Pretty sure a 99 tach will be ECM controlled. The check engine light should come on @ key on and go out in around ten seconds. This tells you ECM is powering up and no active faults. Next crank it. If fails to start, watch the tach. If showing cranking RPM at least 200, your speed/timing sensors are good and you have more of a fuel problem. Needs at least 150 RPM to start. Does it smoke excessive for a couple seconds when it does finally start?

 

I would do the following.

in the morning when you know its not going to start, roll the bonnet over and grab the fuel hand primer pump. pump it until when its firm and on the down stroke you hear a squeak which it the fuel going over relief and out return.

go straight to the cab turn the key to on. wait until the check engine light has come on and gone off again then try to start.

if it starts straight up your problem is in the fuel system. if not its elsewhere

fuel can bleed back to tank or bleed of prime through several places.

• the primer pump
• the return check valve
• the poppet valve in transfer pump
• the primer pump check valve in filter housing
• the inner seal and back up ring on the filter bleed plug also in the filter housing
• injector bodies
• injector orings.
• injector tips

if it still doesn't start after you have pumped the primer before trying to start it when you know it will fault then you'll need to view some data with ET when fault is present