Thump the dash to get it to start... 7.3 PSD E350
- Thread starter Bikersmurf
- Start date
Bikersmurf
Expedition Leader
I'll give that a try next time it's acting up... When it's working, it'll only show I can Hotwire it.
I'm going to to try tightening the neutral safety switch... If it doesn't help, at least it won't show up as a new problem.Thump the dash, and it'll crank, but I can't find anything loose under the dash. I can't make it act up when it's working, and it is intermittent so I can't find the source.
I thought it was related to water in fuel, and for other reasons have changed the fuel filter and rebuilt the fuel bowl.
97 Ambulance Package, E350, 7.3 PSD, Crestline Box.
I'm going to to try tightening the neutral safety switch... If it doesn't help, at least it won't show up as a new problem.Thump the dash, and it'll crank, but I can't find anything loose under the dash. I can't make it act up when it's working, and it is intermittent so I can't find the source.
I thought it was related to water in fuel, and for other reasons have changed the fuel filter and rebuilt the fuel bowl.
97 Ambulance Package, E350, 7.3 PSD, Crestline Box.
I had a similar situation pop up, for me once in a great while my rig wont fire up, until I move the gear selector from park to nutural, then back to park. There is a NPSS (I think its called this) a nutural/park/ safety sw? on the side of your transmission. Where the physical cable hooks to your trans and it has a small set of contacts and if your selector is not spot on you wont be able to start your rig. To adjust the cable you have to remove your PSOM( speedo etc, etc, basically the brain) and turn a little knob that adjust where your indicator lies on the P 123N, this should help make sure your aligned. I found all this out after I had a no start in the backwoods, replaced the starter solenoid, still no start, consulted my electrical prints and said lets try this and bam.. good to go.
Ive been through the dash quit a bit and I dont think anything in your PSOM would give you a no start, matter a fact Im pretty sure I started mine (1994 7.3 idi) with out it plugged in. If you do decide to take your out I would reccomend getting replacement lights at shucks for all your dials and put in fresh bulb, brighten things up a bit.
I hope this helps but next time you get a no start move your gear selector around a bit
Ive been through the dash quit a bit and I dont think anything in your PSOM would give you a no start, matter a fact Im pretty sure I started mine (1994 7.3 idi) with out it plugged in. If you do decide to take your out I would reccomend getting replacement lights at shucks for all your dials and put in fresh bulb, brighten things up a bit.
I hope this helps but next time you get a no start move your gear selector around a bit
Bikersmurf
Expedition Leader
The gear selector was the first thing I tried. Moving it back and forth didn't change anything... Even though PRNOD21 & back.
It'll start without the guaues in at all. Not sure what you mean by PSOAM.
It'll start without the guaues in at all. Not sure what you mean by PSOAM.
UK4X4
Expedition Leader
"I thought it was related to water in fuel"
its electrical !!!!!!!!!!!!!!!!!!
As per I wrote earlier.
You usually only have two things on the start circuit.
Switch - relay - starter
Auto tran may add an interlock to that operation.....switch-interlock-relay-starter
thats for a truck where the solenoid is part of the starter
If its seperate
switch-interlock-relay-solenoid-starter
If you want to sort the issue you have to either
1 trace the fault
2 run a new wire
or you could always check the exaust pipe for dirt and that the blinker fluid isnt too low
these last two have about as much of a connection to your issue as the tire inflation pressure and your reversing light bulb condition, as well as water in the fuel and the moon states relation to the position of Mars in the universe.
meanwhile back to the issue
All the ambulance electrics would come off the ACC part of the switch not the start position
switch find the wires and identify them, power in acc out and start out wire, when you have the symptom check you have sparks at the start out wire
relay- find it.........swap it with another one the same rating and see if that stops the problem, relays can be sticky- bad contacts intermitant function.
There will be usually 2 wires for the coil- 1 of which comes from the start position of the switch, the other goes to earth
There will be two wires for the contacts- one from the battery positive and one to the starter, these will be heavier gauge wire---thicker
With the relay removed you should find 1 earth- one permenant live- 1 switched live(switch) and the wire going to the solenoid/starter
Then your down to the solenoid if installed, sticky starter- sticky solenoid- the later can usually be found by taking a wire from the battery directly to the positive of the starter- solenoid and repeatedly manually keep tripping the starter/solenoid.
It should click and turn every time, depending on model and type these can sometimes be stripped cleaned and resused, or replaced
light bulb tester should be all you need and a bit of 11gauge wire for the starter solenoid short
its electrical !!!!!!!!!!!!!!!!!!
As per I wrote earlier.
You usually only have two things on the start circuit.
Switch - relay - starter
Auto tran may add an interlock to that operation.....switch-interlock-relay-starter
thats for a truck where the solenoid is part of the starter
If its seperate
switch-interlock-relay-solenoid-starter
If you want to sort the issue you have to either
1 trace the fault
2 run a new wire
or you could always check the exaust pipe for dirt and that the blinker fluid isnt too low
these last two have about as much of a connection to your issue as the tire inflation pressure and your reversing light bulb condition, as well as water in the fuel and the moon states relation to the position of Mars in the universe.
meanwhile back to the issue
All the ambulance electrics would come off the ACC part of the switch not the start position
switch find the wires and identify them, power in acc out and start out wire, when you have the symptom check you have sparks at the start out wire
relay- find it.........swap it with another one the same rating and see if that stops the problem, relays can be sticky- bad contacts intermitant function.
There will be usually 2 wires for the coil- 1 of which comes from the start position of the switch, the other goes to earth
There will be two wires for the contacts- one from the battery positive and one to the starter, these will be heavier gauge wire---thicker
With the relay removed you should find 1 earth- one permenant live- 1 switched live(switch) and the wire going to the solenoid/starter
Then your down to the solenoid if installed, sticky starter- sticky solenoid- the later can usually be found by taking a wire from the battery directly to the positive of the starter- solenoid and repeatedly manually keep tripping the starter/solenoid.
It should click and turn every time, depending on model and type these can sometimes be stripped cleaned and resused, or replaced
light bulb tester should be all you need and a bit of 11gauge wire for the starter solenoid short
Bikersmurf
Expedition Leader
Nice rant...
Since its DIESEL, and the water in fuel light was on, and draining the fuel bowl resolved the starting issue, it's not something random.
Perhaps I should rewire the truck, replace the glow plugs with spark plugs, and add a coil. That'll fix it for sure.
Since its DIESEL, and the water in fuel light was on, and draining the fuel bowl resolved the starting issue, it's not something random.
Perhaps I should rewire the truck, replace the glow plugs with spark plugs, and add a coil. That'll fix it for sure.
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UK4X4
Expedition Leader
"Fuel bowl is rebuilt and reinstalled. No water in fuel bowl.
But the problem has recurred... "
hey you wrote the above........................................prase be the lord. a miracle. once dead and now alive 6 posts later
I added a little sarcasm, I know I should of added instructions for that too.
when some one asks a question we all try and answer to the best of our abilities...........
obviously I need to pray more as miracles obviously do happen
But the problem has recurred... "
hey you wrote the above........................................prase be the lord. a miracle. once dead and now alive 6 posts later
I added a little sarcasm, I know I should of added instructions for that too.
when some one asks a question we all try and answer to the best of our abilities...........
obviously I need to pray more as miracles obviously do happen
Bikersmurf
Expedition Leader
As stated originally, it's an intermittent problem. No miracles here, just very hard to diagnose. Possibly even a number of overlapping problems. Yes there likely is an electrical problem... But there have been other factors also like a filthy fuel bowl and a black fuel filter.
I apreciate answers from a knowledgeable group of people... But people need to remember its a DIESEL, and water in fuel will create a no crank issue from the ECM. Unless I've misunderstood something, and should just check that I've got power at the coil and replace the spark plugs,
I apreciate answers from a knowledgeable group of people... But people need to remember its a DIESEL, and water in fuel will create a no crank issue from the ECM. Unless I've misunderstood something, and should just check that I've got power at the coil and replace the spark plugs,
Ok ill try to help out.
When it is acting up check if you have power at fuse 34 in the instrument panel fuse box while cranking or holding it in the cranking position. Itll be a 10a fuse.
If thats ok next inline is the transmission range sensor. Wht/pnk should be power from igntion switch in start. Red/light blue is power signal out.
If thats ok, the starter motor relay could be the culprit. Its under the hood on the passenger side by the battery.
The pcm has no control over the engine cranking, so the water in fuel light wont keep it from cranking.
The thumping of the dash could be coincidence or it could be making that relay you said you heard click function. Its kind of hard to know. Could you get a picture or maybe a number off said relay? It would help.
Im basing all this info off a 1997 e350 cutaway, so the ambulance company would have added some wiring. But its a start and hope it helps.
When it is acting up check if you have power at fuse 34 in the instrument panel fuse box while cranking or holding it in the cranking position. Itll be a 10a fuse.
If thats ok next inline is the transmission range sensor. Wht/pnk should be power from igntion switch in start. Red/light blue is power signal out.
If thats ok, the starter motor relay could be the culprit. Its under the hood on the passenger side by the battery.
The pcm has no control over the engine cranking, so the water in fuel light wont keep it from cranking.
The thumping of the dash could be coincidence or it could be making that relay you said you heard click function. Its kind of hard to know. Could you get a picture or maybe a number off said relay? It would help.
Im basing all this info off a 1997 e350 cutaway, so the ambulance company would have added some wiring. But its a start and hope it helps.
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Bikersmurf
Expedition Leader
Thanks, I'll check those next time it's acting up.
I guess I'd misunderstood about the Water in fuel error. It's been a real learning curve. I hate complex computers and such.
They started with a cutaway, so it's a good starting point.
I don't think thumping the dash is a coincidence... It has worked 8 or 10 times (every time). It might be a bit till I have a chance to take a pic of the relay(s)... The dog house will have to come out to even get near them. It's under the dash at the left rear corner of the radio, and it can't normally be seen or reached.
I guess I'd misunderstood about the Water in fuel error. It's been a real learning curve. I hate complex computers and such.
They started with a cutaway, so it's a good starting point.
I don't think thumping the dash is a coincidence... It has worked 8 or 10 times (every time). It might be a bit till I have a chance to take a pic of the relay(s)... The dog house will have to come out to even get near them. It's under the dash at the left rear corner of the radio, and it can't normally be seen or reached.
I have a 1997 RB E350 so ill check what relays are in that area. During a quick look, it was just relays for ABS and other relays not associated with starting.
Possibly theres a bad connection from the ignition switch and the thump makes the contacts touch. Maybe a poorly spliced wire. Checking for power at the fuse will determine if its an ignition switch wiring in the column/dash area or farther down the line.
Possibly theres a bad connection from the ignition switch and the thump makes the contacts touch. Maybe a poorly spliced wire. Checking for power at the fuse will determine if its an ignition switch wiring in the column/dash area or farther down the line.
Bikersmurf
Expedition Leader
That's likely the problem. Usually it works fine, sometimes there's a split second delay, and once in a while nothing. Sometimes it works if I leave it a minute and try again, sometimes it still doesn't thump the dash and it always cranks.
If I understand correctly, it should crank when the key is turned with no delay and the computer (or anything else) has no bearing. I know that's how it works in my older vehicles, but I've also got a car with a push button power switch that doesn't even start the motor. So I've just been trying to understand what I'm dealing with. All else fails I'll just need a priest to cleanse the spirits from it.
If I understand correctly, it should crank when the key is turned with no delay and the computer (or anything else) has no bearing. I know that's how it works in my older vehicles, but I've also got a car with a push button power switch that doesn't even start the motor. So I've just been trying to understand what I'm dealing with. All else fails I'll just need a priest to cleanse the spirits from it.
Bikersmurf
Expedition Leader
Of usually acts up when my wife and kids are loaded up and we are late leaving... In that case I wack the dash and get on the road. Later when I have time to investigate, it works 100%.