Question about 1991 Ford F250

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Engine Problem I was running for over 1 year on Propane since my Gastank was leaking. I changed the Gastank and run the propanetank empty. Now when i start the engine it is vibrating like crasy,tried it on propane again and it does the same thing now.sounds like its not running on all 8 cylinders but cannot figure out why. Thanks for any help

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It could be dual fueling manualy isolate to guarantee you are running on one fuel at a time

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You may have to use different methods to test vacuum. Some use vacuum gauge to test egr and lines which dead end into solenoids. Other tests use water spray or propane gas to draw in and change rpm. You are at a disadvantage if engine does not run.

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I have a 1992 dodge dakota that gives me a code 27 n tells me cyl.#5 misfire, have checked compession n its good ,dist. good spark is good ,replaced injector n computer tells me faulty control module n it...

Hi there,
Have you tried vacuum leak test?
What you would need is a common shop propane torch.
How you use.
1. Start your engine. take the propane torch (Don't light it!!!) crack open the valve.
3. point the valve at each vacuum fitting on the intake manifold.
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Also check where the intake meets the head.
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I hope this help. Give feed back if this helps anyone. Fixya

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