Hello everyone, this is my first post here but I’ve been using the forums resources for little over a month now... I have a situation with my bus. It’s a 2000 e450 minibus. With 7.3l PSD. I am converting it to travel and live in, but at the moment cannot get it started.

A little background might help. I bought the bus at the end of July or beginning of August 2021. Everything appeared fine with the engine and chassis even at 230k. Blow by was minimal, smoked a little on startup but quickly went away.

The next couple of weeks I drove it everywhere with no issues. I decided to go camping and could not get the bus to start in the slightly colder, slightly higher elevation. (Phoenix to Dewey for those wondering) had to tow it home, 700 dollar tow and ride back into town.... bummer.

I got it home the following day, and decided to take it to my shop. It started no problem, warmed up and drove fine. About 30min down the road, headed up a small hill. I experienced a loss of power. The temp gauge spiked. And looking in the rear view while trying to get over, the exhaust was BELLOWING black smoke.


Since then (Halloween weekend) I cannot get the motor to start. It will crank but not start.

I’ve confirmed;

All fuses and relays in working order. In all locations. Under hood and under dash.

2 new Deka batteries (880cca) (JAN/2022)

power to the fuel pump, KOEO about 15-20secs

Fuel pressure post fuel filter: 60psi
(While cranking and KOEO)

New fuel filter

WTS light is there and turns off like normal
Service Engine light comes on and turns off like normal

GPR Has voltage in and out
glow plugs ohm out correctly

I bought a scanner and found I have error code P1280 (ForScan and OBD MX+ Bluetooth)

I’ve tried cranking with icp disconnected, no difference.

Hpop builds pressure and has oil in top inch of reservoir

icp reads pressure during live data 500+ psi
icp reads 2465.7psi unplugged while cranking

Rpm’s while cranking are 100+ (usually 160-180)

IPR duty cycle 14.8% KOEO
IPR duty cycle 64.8% while cranking

I even replaced the CPS for fun.


I’ve now gone through the icp pinpoint test section in the manuals I’ve found on this forum.

everything checks out until step DC6. Maybe I’m backprobing in the wrong spots? Does the pcm need to be connected Or disconnected to the harness while testing between pins??

I’m looking for some opinions or concerns before diving into finding a short to ground... Because that’s what the pinpoint test is pointing me toward. And specifically a short to ground in signal wire circuit #812
(or #535 for the econoline vans)

thanks for reading through. I’ve found more than what I was looking for joining this forum. The info and brain power on here is a plenty. Very appreciative of you ford wizards

 

TTT during the day, also, don’t be scared of the bus factor. It’s just a big van haha. Really itchin to get some help, I am not an electrician by any means.

Simple stuff with directions, sure, no problem. But this is getting to be a bit out of my league.

 

Black smoke indicates a fuel to air ratio problem. Have you checked your turbo? Have you figured out what made your temp spike? I am not certain but that fuel pressure seems a little low, shouldn't it be around 60 or 70?

 

Welcome to FTE! Some more knowledgeable guys will be along shortly but in the meantime I would recommend looking into the "no start flow charts" in the tech folder under the sub title "Diagnostics". Seems like you have done quite a bit of testing but these may help if you haven't gone through them already. I am assuming you already checked continuity between PCM plug and ICP?

 

I never removed the turbo but the arm on the turbo is in the open position. And the turbine spins freely with no play or noise. What should I be looking for involving the turbo?

Not sure how to figure out an over heat situation when the truck won’t run. But I figured the temp spike was a side effect of the loss of power situation. It was October in Phoenix. Temps during the day were probably 85/95 degrees. Yes in October.

I had one other incident with a temp spike and I feel it is unrelated. But the day I drove it home one of the heater hose lines had a pin hole from rubbing the exhaust. Busses have a separate heater box in the back for the kiddies. Removed the cabin heater and lines. Routed the coolant hoses to eliminate the cabin heater and the cabs heater core all together. So coolant flows out the thermostat and directly back into the block. No coolant or temp related issues until it broke down while driving.

I downloaded a copy of a manual here saying 30psi is in range? My understanding was 60psi directly out the pump. Once it goes through the regulator and fuel bowl it’s about 30/40psi. Also I noticed the no start flowchart says fuel pressure >20 is acceptable?

Not arguing, just want to verify the correct values so I can determine my testing is true or false.... I purchased some fuel bowl adapterS to test the pressure going into and out of the fuel bowl for easy testing, so not a big deal to restest.

 

I’ve done about every test you can do for free. I’ve even bought a scanner and dongle to further my testing. I have read almost every trouble shoot sheet and ford diagnostic sheet in the tech folders above. Going through the ICP pinpoint test I believe test DC3,4&5 verify resistance and continuity between pcm. Again, I’m not sure if I’m doing the pinpoint tests correctly at the PCM. Do I need to back probe the harness while pcm is plugged in? Or remove pcm from harness connector and check values at pins in the plug itself?

 

Most will tell you that you need to back probe the back of the PCM harness but I have never been successful back probing the PCM harness given its location in our trucks ( not sure if your van is easier access or not). I have had good luck unplugging the PCM harness and probing the pins with a pinout diagram. This is not to be done with regular DVM test leads, if you get the really skinny test leads, they are almost almost as thin as a needle, you can put those in the pin Holes without causing any harm.

 

I know you said you're getting 500 PSI from ICP while cranking which I think is on the cusp of the engine starting, can't remember if you need 400 PSI or 500 PSI before the engine will start. Did you install the IPR duty cycle% PID on forscan to see what the IPR is doing also?

 

I have the Test pins you speak of, and I’m sorry but I still am not sure where u probe at. If you are looking at the pcm in the engine bay, do you probe where the wires enter the plug? Or remove the plug and probe into the sockets that plug into the pcm? Also, am I supposed to do this with the pcm attached to the harness or no?

 

thank you I forgot to mention that. Looking through different manuals and resources, I can’t seem to find the IPR’s duty cycle percentage while cranking. But I am getting 14.8% KOEO and 64.8% while cranking

 

I remove the PCM and gently put the skinny test lead in the female holes of the PCM harness.

 

Your IPR seems to be functioning properly. I could be wrong but I would think that you would be getting more oil pressure with the IPR wide open and a properly functioning hpop system while cranking for a bit. What is the forscan ICP value with it unplugged while cranking? I think the default setting should be somewhere around 750 PSI.

 

when I crank with icp unplugged, FORscan shows me 2465.7psi. Hmmmm

 

I'm sorry I was thinking 750 PSI when the engine is idling not cranking. With the ICP plugged in does it reach 500 PSI Max when cranking? Does it take a while to get there or does the pressure shoot right up? I know you said you have new batteries but are they charged up good? the flowchart says a minimum of 200 RPMs while cranking but seems that I remember you can get by with 180. Your RPMs are right on the cusp and so is your ICP. Does the engine sound like it's struggling to crank or does it sound strong?
Is the fuel level above a quarter tank?

 

yes icp reaches 500+ psi when cranking, it will take a while to build up only if I haven’t tried cranking for a bout a week or so. I’m assuming because the hpop res bleeds back down into the oil pan?

yes, I actually just installed a noco 2a battery tender. I plug it in after doing any testing to ensure batts are charged next time

When I listen to other people’s trucks with 7.3l (customers, friends and neighbors) mine sounds sluggish compared...but it sounded the same next to my buddies when running at idle.

Yes, I believe so. I filled the fuel tank full when I went camping and never went below half by the time it got towed home. It’s a big tank, I think 60 gallons. I can always double check though