OK So our SAR team has a converted ambulance we use for our Command Post. Wednesday morning we had a search at 1AM. Vehicle drove to search and ran until 10AM with no issues. Shut vehicle off with 1/2 tank fuel. This morning we were dispatched to a call at 04:30 and the driver called on the radio to say it wont start. When i arrived the fuel in water light was on. Being it was a rain snow mix I decided to skip taking the vehicle. I went back later this morning and tore into it (E series are a PITA). After an hour I could finally get to the filter. I drained the water and saw really nothing but fuel. The filter looked bad and have no idea when it was replaced, so replaced it with a new one. Still will not start. I did remove the filter a couple times and the pump is flling the "filter" housing with fuel so dont think it is a fuel issue. The truck has a 190,000 of hard use but has been running fine for the last year. I get some movement on the oil pressure gauge (factory ford idiot gauge). No smoke from tailpipe. Spraying ether in air hose fires. I did check all the fuses others said to check (actually checked every fuse in dash and under hood panel).

I also replaced the ignition switch as we have had it not shut off a few times in the past requiring us to toggle the switch back and forth. New one is in and all power appears correct per pin.

 

1st...do not spray Ether as you will destroy the motor.
2nd...replace the CPS....this way you know for sure that is not the problem then post back up please.

 

CPS ? Camshaft Position Sensor ? Where is it on the engine ? Is it even possible to get to without pulling the radiator ? I know know why no one wants to work on these trucks....

 

Yes, Cam Position Sensor. It is easy to change. You can follow the wire to it. It is located just above the balancer to the left (looking at the front of the truck). You will need a 10mm wrench/socket.

 

OK...apparently you have never worked on a E Series 7.3...Fro the top of the engine you cannot even see any wire harness other than the one that leaves the huge alternator. I'll crawl under the van and see if I can get to it from under the vehicle. It will be morning until i can see if any stores have it and try to replace...thats if i can find a store open.

 

Yes, it is done from underneath...sorry I didn't mention that...lol

 

I recommend the Ford dealer..but Napa will work in a pinch...sometimes...lol

 

Do you still have the "wait to start" light? If not then fuse #22 is blown under the hood. It powers the PCM and fuel filter heater. If the fuel filter heater shorts out, and they do then it kills power to the computer. Also "water in fuel" can be caused by someone power washing the engine bay. You don't really have any water in the fuel but some electrical connections get wet causing a false signal.

Sometimes you cant see fuse 22 blown so you need to either measure it with an ohm meter or just replace it. Believe it's a 30A maxi fuse. However if you do have a "wait to start" light then all the above is for not.

Edit: On the engine keeps running with key off can be caused by a bad glow plug relay, believe it or not. A short in there causes a voltage feedback through the key which keeps the PCM alive. So if that issue comes back replace the relay.

 

WTS light does come on. When trying to start the WIF and Engine Temp light is on. I checked all the fuses (engine bay module has no cover) and even removed and reinstalled them to verify. I called all over and the only place i can get a CPS is Autozone in the morning so will try this. If that solves it I will order one from the dealer during the week. I really want to get the vehicle in service as we carry all our search and rescue gear along with all our computers and radios in it.

If that doesn't fix it i guess its hooking a computer to it to determine what is really wrong. It has a tach, but its the digital one on the power control module for the high idle and doesn't show a RPM until running. Being there is nothing from the tailpipe i am confident it isn't getting injectors fired.

I'll check the relay. We thought it was the ignition switch as the lights and radios would stay on (and being its a 1995 with over 50,000 ambulance calls on it) thought maybe it had been on and off a few too many times. None of the local dealers will touch it due to it being a E-Series so we are kinda stuck on our own until we can find a replacement vehicle.

 

I would NOT just swap the CPS for its own sake, esp. for a parts store CPS. There are enough other things that could be wrong. And the parts store sensors are notoriously bad. FIRST thing I'd check, since you had a WIF light, would be fuel pressure. The bowl filling only shows that the first, low-pressure stage of the fuel pump is working. That won't tell you whether the main stage that feeds the injectors is working. I would get a cheap fuel pressure gauge on the schrader valve on the FPR.

 

Hmmm....well I would being as they are suspect on every no start on the 7.3. Even if it doesn't solve his issue, he needs one in the glove box for the time he does need it. It's not like it's a 100.00 part that won't ever be used.

I agree with not getting it from a parts store such as Autozone, but would wait for Monday to get one from the dealer.

The 7.3 will still run with the WIF light on....mine did lol

 

So would a standard OBDII Scan tool tell us anything ? The parts store says we can loan one out to check the codes if it would show anything. Guy at the store didn't know anything on the 7.3

Being every post i come accross via google says the CPS causes this issue i am going to change it as i had planned. If it starts great. If not I'm only out a few $$.

 

Most parts house code readers don't speak 7.3 powerstroke. They will plug in but don't communicate.

 

All - Found a CPS at AutoZone (Napa closed today here) and replaced it and she fired right up. Unfortunately the fuel filter i installed was leaking like the titantic so after dumping a gallon of diesel on the ground I removed the filter and used the gasket off the old filter and the reassembled everything.

As reference the E-series requires tearing a ton of stuff apart and with our vehicle this includes removing our laptop mounts, radios, light controls and a ton of other stuff just to get the dog house off. With any luck we wont need to replace the filter until next year.

The CPS was tough but i was able to get a deep 10MM socket on it and a 3/8 ratchet to break it free, then used a 1/4" ratchet and socket to remove the rest of the way. The bracket is a rusted clump so i am guessing it may of been on the truck for the last 189,000 miles ! Anyway as i said i got the autozone one. It has a lifetime warranty from them, but i know many say the FORD one is the best. So is it really worth ordering one from Ford or just throwing another cheap one under the seat ? Our plan is to replace this truck, but we only make so much from fundraisers a year. It runs well but has lots of exhaust leaks and is rotting off the frame rails.

 

OK I forgot to add this to the last post but everything appears good now, except it does not shut off when we shut off the switch. If you move the switch back just a bit you can get it to shut down. Is the relay in the box under the hood ? All our radios and lights are now shutting off so the switch was bad.