Hi, brand new here so hello to everyone. I was just about to sell my truck, in fact my wife had already paid to have it listed. Before I got a chance to get the pre transfer smog done (California thing) the engine light came on. Took it in to get it checked and it turned up codes PO304 PO306. Shop tested plugs and wires and recommended them changed. Gave them the go ahead and they started on it. Checked compression while doing tune up and they said the #6 cylinder has low compression, 60 PSI. Thought maybe some carbon was sticking a valve so they tried cleaning it with chemicals, didn't help. They are saying it is most likely a burnt valve. They finished the plugs and wires and the #6 cylinder is still misfiring. Anyone have any experience with this? The mechanic himself said he hasn't seen this before on the 3.0 motor. Any other possibilities (hopefully cheaper ones) or am I stuck having to take the cylinder head off to check? This is a 1998 ranger 3.0 xlt ext cab 4x4 with 128,000 miles. Thanks for any help you can give. Also I don't have much in the way of tools so I'm afraid I can't check too much out myself.
I would reset the computer and see if you can squeek by on smog and get it sold without the light turning on. Other then that, you most likely need a valve job, or you can just trade in the truck. they would check if the light is on or another thing.
Always wondering about someone else turning wrenches on my vehicle the first thing that I would check is that the spark plugs are torqued to the right specs and that the threads for the #6 cyl. are ok. Be very carful not to overtighten the plugs since they are threaded into aluminum. Other than that if you have an internal engine problem you could take the instrument cluster out and pull the bulb for the check engine light and ship the truck.