I picked up this 2000 f150 that is bi-fuel, gas and propane, but it will not start in the propane mode, any body have one of this and know what might be not letting fuel from the propane tank in to the engine, this is a factory made ford propane

 

well, I have a f250 dedicated cng and nobody even techs know how to fix these things, I have learned alot by talking to people online, jerks too and I would tell you to start at the fuel filter. Mine is right before the fuel pressure regulator. If you have changed it recently that may not be the problem. As I did with my no start problem I then tapped into the fuel rail and measured the fuel pressure which will tell you if you have the correct pressure. If you do as with mine you may have a faulty fuel pressure sensor. I unplugged it, held the gas pedal half way down and the bitch started right up. They can end up out of range and send faulty info back to the cpu. I drove my truck 200 miles to the nearest CNG tech in LA and he confirmed what I found out, that the fuel pressure sensor was faulty and would cost 205 buck.....ouch this stuff is not cheap. You may also have a bad cpu but if the truck will run ok on gasoline it may be fine and not the real problem.

So make sure you have propane..........check the fuel filter as it may be clogged, check the fuel pressure if the filter is ok, you may want to pull out an injector they have these super fine filter screens in them and mine were almost clogged shut, I had one faulty injector and my truck would not start so do not skip this step at least you will know what they look like inside. Yank the plug off the fuel sensor and see if it starts, if not you may have a bigger problem but all this stuff I mentioned will only cost you time.

Tell me what the problem is should you find it. I am going to convert my cng over to propane but with a carb manifold and not expensive computer bs and it will still pass the smog test where I live.

 

I to have a E350 that is dedicated CNG, I love it. I fill up at home for a $1.05/gallon. propane seems great though with the amount of fuel you can get in a tank. The one thing that I have figured out is that when you have a bi-fuel some things have to be shared like the fuel injectors and it is better to have something that is dedicated. Like your cng, the injectors are set up for just the cng and should not need much service. I just moved from socal and have found a specialist at my local ford dealer that is very knowledgble
Hopefully he can figure it out. I think the cpu on the fuel injector propane system. I will check the other stuff though. I can hardly even get to the plugs with all of the fuel injector pipes and the propane cpu control section.