Thanks edward t , you were right on the money with that one, It was the injector. Thanks I owe u one.
this one won't even clear the codes if the battery goes dead, so no, you don't have to relearn after the battery goes dead. I don't know of any way to accurately check the injector with an ohm meter, It is the one held in with 4 screws, and the fuse you mention, and you just take out the screw, and pull it straight out and feel the plunger.
hey Edward? you mentioned a computer relearn, If the battery goes dead does the computer have to be relearned? Most have a computers have a internal memory but it's just a thought.
what is the large solenoid the rear of the mixer, it is round shaped with a inline 5 amp fuse attached to it? It is located where the propane comes into the mixer along with a few sensors.
I'm used to the impco lpg systems, I've never seen this new design yet, It has a nikki vaporizer so is this a aisin or nikki system? ANyways, To me the front of the engine is the water pump side too. I was just suggesting this black unit on the mixer for a starting point on where to look. how do you test the solenoids if they are stuck? Is there a ohms specification?
I think you have pretty much described the main injector, you may find that just taking it out and putting it back in cures the problem. (plunger might be "hung up").
However to me, the "front of the engine is the water pump side, not the bell housing/transmission side, which would mean (in my memory) the injector was towards the front of the truck, which is opposite the front of the motor.
We get our propane from a propane dealer in town, more than likely filled from a bulk tank but all of our lift trucks use the same tanks we just rotate them. So that likely is not the problem. BUT, Is this the large black solenoid at the bottom of the mixer at the front of the engine? Not sure if the computer was changed recently, hopefully not as I do not have the laptop.
Try replacing the large solenoid on the mixer, if you have a 'known good' one. they stick sometimes, usually when new. if this is a new truck, or the computer has been changed there is a "learn" procedure that needs to be run with a laptop computer.
ALSO what is the temp when filling the LPG tank, and is the tank filled from a bulk tank (outside) without a pump? (gravity feed). if you fill the tank when the tank is warm, (say from working inside at 3 PM) but the bulk tank cold, (from sitting outside) then when the truck sits outside overnight, the pressure may be changing quite a bit.