1980 Jeep Grand Cherokee Repair Question
Knock Sensor, Fuel Filter, clogged injectors, something worse???
First of all, are you getting a check engine light? Because if your knock sensor has failed, you should get one.
Also, check your fuel pressure, fuel pressure regulator for leaks, and clogged filter, injectors (also leaking injectors). These won't show up as engine codes, but will cause the problems you described.
My check engine light is not on. Can anyone explain why the symptoms only occur during acceleration past 60mph? Gas mileage isn't being affected (according to the computer). Acceleration through gears 1-3 up to 60mph run strong and clean without symptoms.
3 questions asked
It's either an ignition system failure, sensor failure, or fuel system failure.
When you have an ignition system or sensor failure, the computer usually picks up on it, after all, that's what it's designed to do.
With the fuel system, the computer will only detect a "multi cylinder misfire", but won't know what's causing it. This is why I suggested you check the fuel system components.
Having said that, an intermittent failure with the ignition system or sensors won't always set a computer code. But they're easily checked with a capable scanner during a live data test.
Fixing your problem will be a process of elimination, and unfortunately, I can only point you in certain directions based on the information you provide.
Remember this, instead of replacing parts in hopes of fixing your problem, take a logical approach and test each component. This will save you money and time.
Start with the fuel system.
Thanks for the advice Ernest.
Its sounds like I have a fun Thanksgiving Holiday project.
3 questions asked
No problem. If you run into a particular procedure that you need help with, let me know and I'll try to help. The more specific you can be, the more I can help.