Have you checked to make sure you've got 12V on one side of each injector? May have blown the ECMA or ECMB fuse...
CK5
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Truck won't start SOLVED!
- Thread starter cbbr
- Start date
I checked the voltage to both sides at the pulg and got 12vc. I also checked the ECM fuses in the fuse block (drivers side, inside). Are there others?
Wait, you've got 12V on both terminals? One side should be open loop to ground (or very, very high resistance) and the other should be 12V. 12V on both sides = no current flow = injectors not working...
You can put a marker light bulb between the two terminals of each injector and have a friend crank the engine while you look for the light to dimly flash. If that is working and you've got no fuel coming out, try cracking your return line open and see if there is any fuel coming out. If not, you've got a major blockage somewhere.
You can put a marker light bulb between the two terminals of each injector and have a friend crank the engine while you look for the light to dimly flash. If that is working and you've got no fuel coming out, try cracking your return line open and see if there is any fuel coming out. If not, you've got a major blockage somewhere.
I unplugged the line to the fuel pump, wired both sides and tested both sides with a multimeter (cheap) with the key in the running position. Both sides were running 12v. Am I checking it wrong?
Ah, sorry, I meant to check the voltage at the injectors, not the fuel pump! Now I understand why you've got 12V on both terminals (that is a good thing, BTW...)
Just pop your air cleaner off and pop the plugs off the top of the injectors. One side should be 12V with the ignition on, the other side should be open to ground. If you hook a marker light, noid light or 12V LED up in between the two terminals and crank the engine, you should be able to see the injector pulse. If it doesn't, then the ECM isn't recieving feedback from the ignition module in the distributor on the white wire indicating when the ignition is firing.
Just pop your air cleaner off and pop the plugs off the top of the injectors. One side should be 12V with the ignition on, the other side should be open to ground. If you hook a marker light, noid light or 12V LED up in between the two terminals and crank the engine, you should be able to see the injector pulse. If it doesn't, then the ECM isn't recieving feedback from the ignition module in the distributor on the white wire indicating when the ignition is firing.
Thanks! I will check that this evening.
I worked the multimeter prongs into the caps, one on each side - turned over the engine and nothing. Not a blip. Assuming that I had good contact, what next?
Someone correct me if I am wrong, but I think there is always 12v at each injector with the key turned to "on" or "run" and it is the ground that pulses. I would check the 12v side of the injector and place the other probe on a chassis ground to make sure you are getting the 12v supply to the injectors. You can remove the connector if you want) If it shows 12v, you know the injectors are powered, just not receiving the signal to pulse. If no 12v, check the fuse(s) for the injectors.
Without bveaking them (I am bad for that), how do you get them out?
That I don't remember...there is usually a little clip to release. If you always break them, just do it the same way you did before.
The good thing is, you only have to turn the key on, you don't have to crank it.
Yep, with the key switched to on, the white wire on one injector and the red wire on the other one should have 12volts to ground.
If not, then you probably have a blown fuse.
You probably will not see a pulse with a meter as you crank, because its too short.
Check for 12 volts and let us know.
If not, then you probably have a blown fuse.
You probably will not see a pulse with a meter as you crank, because its too short.
Check for 12 volts and let us know.
To remove the connector just pinch the releases on the top of the connectors and pull up 
Thanks, that's what I thought. But they offered some resistance and I just could not bring myself to break anything else.
Alright, the fuel pump is kicking in, it has new gas & fuel filter, the battery is topped and the injectors are getting power. It runs on starter fluid, but dies. What next?
If it runs on starter fluid, then you are not getting gas. If the pump is running, and you have pressure at the injectors, then they are clogged or not firing.
You should be able to get a piece of cardboard or something under an injector while cranking to see if its spraying.
Remember, the injectors are fired by grounding them. IOW, they have 12 volts on them all the time when the ignition is on, but the computer grounds the other lead to turn them on.
If the computer is not firing the injectors, then either a wire is bad, the computer is bad, unlikely, or its not getting the signal to fire them.
Which, I think, comes from the ignition module on the dist.
All this, is assuming that someone has not stuck a hose in your tank and filled it with water...............
Unlikely, perhaps, but I saw it one time. Took forever to figure out why the engine would not run on water.......
You should be able to get a piece of cardboard or something under an injector while cranking to see if its spraying.
Remember, the injectors are fired by grounding them. IOW, they have 12 volts on them all the time when the ignition is on, but the computer grounds the other lead to turn them on.
If the computer is not firing the injectors, then either a wire is bad, the computer is bad, unlikely, or its not getting the signal to fire them.
Which, I think, comes from the ignition module on the dist.
All this, is assuming that someone has not stuck a hose in your tank and filled it with water...............
Unlikely, perhaps, but I saw it one time. Took forever to figure out why the engine would not run on water.......
Crazy question, but I recently unhooked the ABS (new MC/discs/calipers/prop valve, etc). But we just disconnected the ABS. Would that cause it to not start for some reason?
BowtieBlazer
Diesel Powered
Chad give me a call I'll be more than happy to give you a hand when you have time, I've got a pretty open schedule.
Thanks, I may well need the help. The fact that it won't start is all that protects it from being sold some days...
Done - no fuel spraying.
So the battery is topped, fuel pump sounds like ita working (and is hot according to the multimeter), new fuel filter, most of the gas is new and the injectors are getting current per the testlight (testing one to the other). Help!
Help the fuel system newb please.
