No start

This is a symptom of a timing issue. Either valve or ignition. Do you have any trouble codes?

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Rich

Hi,

Check the distributor cap and rotor for cracks and corrosion the cap could be cracked. Check the spark plugs, wires' cap and rotor should be changed every 50,000 miles on that truck. Check for vacuum leaks hoses and intake manifold I'm attaching repair guides for you to reference. Let us know if you need more info.

https://www.2carpros.com/articles/engine-backfires-while-running

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Thank you
Joe T.

There are no engine codes. I failed to mention new cap and rotor.

It has kinda low mileage to have a bad timing chain but it could just be a bad chain. It's fairly easy to do a compression test and find out if the chain hopped a tooth or 2. I would do one just to rule it out and maybe get some info on the health of the motor. If you don't have a tester you can rent one for free from most parts stores.

https://www.2carpros.com/articles/how-to-test-engine-compression

Rich

Hi,

Unplug the mass air flow sensor if stops backfiring when it is unplugged replace it. Check the hall effect sensor it is the plate under the distributor rotor. check for misalignment or damage. The camshaft sensor is right below that it also could be misaligned or damaged. It could also be the crankshaft sensor check the wires for chafing or loose connection the sensor may need replaced. I'm attaching exploded parts below so you can find them for inspection. All these parts I have mention have a part in ignition timing and can cause the engine to backfire. Let us know if this was helpful or if you need more information.

Thank you
Joe T.