Truck died on the road. Will crank, but not start!

Is the engine light on?
Can you hear the fuel pump running when you turn the key? Listen carefully. Check your battery cables.

The engine will not just die at 50 mph if the fuel pump is running. Low fuel pressure or a clogged fuel filter will not kill the engine, it will make it run rough---sputter---and such.
To be sure your getting fuel take the air cleaner off. Have someone crank the engine while you look at the injector where it sprays into the throttle body. If there is fuel there it's not the fuel pump. Let me know.

Ok now we're getting somewhere! Next you must check for spark. The easiest and safest way is to get a spark plug tester. Click on auto parts from this site. Click onto jcwhitney. Com and type in spark plug tester. You will see the type I have. Many auto parts stores have this type or something very close to it. Do not just take the plug out and plug in the spark plug and see if there is spark. Remember there is fuel getting to the motor. Just a word of caution.I found out that one the hard way. But thats a story for a different time. If you go changing random parts you could run into some big bucks, take one small step at a time. Let me know.

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You have fuel entering the motor so it's not a fuel delivery issue. No spark. AH HA. Well my friend there are a few things it could be. The ignition module is one of them. First, BEFORE you change it, have it tested. It is rare that a module will just die at 50mph going down the highway but I guess with over 200,000 miles on the truck it's possible and it's probably time for a new module anyway. I know autozone, or a place like that, can test the module for free. If you still have the old coil they can test that also. Make sure the coil wire is connected. Take the distributer cap off and bump the ignition key to be sure the rotor is rotating, sometimes the distributer gear stripps out with high mileage. Take some time and follow all the small wires that plug into the back of the distributer cap and all the wires that plug into the module. Look to see if they are broken or are rubbing up against a hot exaust manifold or pipe or something like that. It's not as bad as it sounds just take care to look close. Try not to go changing things until you confirm that the item is bad. Doing so can easily lead to the bill adding up---your blood pressure rising to unhealthy levels---and a lot of time waisted. This also could be an oil pressure issue but lets cross that bridge when we come to it. If we come to it.

Glad to help-- but you did the work. Good luck!

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