1996 Bronco 5.8 with E4OD

The engine currently in the truck is a replacement engine installed about 7 years ago. Within this time period I hardly drove the Bronco, so in

a sense the truck sat idle. I started driving the truck daily about 4 months ago and the other day a condition started.

1. The truck idles fine, without a sign of a misfire and no noises that would indicate a problem.

2. At 1500 RPM there seems to be a noise that sounds like a damaged bearing rotating/tapping.

3. At 1500 RPM under load there seems to be a miss (like the truck is running on 7 cylinders) and a lack of power.

The conditions occur AT 1500 RPM and above.

Could this be a valve train issue? Distributor? Oil pump?

I donʻt think any accessory belt driven part(alternator, AC compressor, power steering pump, water pump, etc) would cause a miss.

So what else would cause a "squeak/tapping" internally with in the engine?

 

when was it tuned up last? how about oil change? probably wouldnt hurt to replace the fuel filter as well.

 

There was a damaged header gasket, yes, and the fuel filter was replaced and the

injectors were cleaned. The CAT may have to be replaced since it is causing a CEL right now.

It runs good for now, but itʻs life as a daily driver may be limited in the near future.