I want to miss my miss

ford
ranger

#1

Yes, it’s been a year and my '99 ford ranger still has a miss. It’s worse at low rpm, high load and seems to get a little better at higher rpms. I’ve been working on this for some time and here is most of the things that I’ve done to try to get rid of it. HELP!~





*new plugs and wires about 10,000 mi ago, gapped because the guy at the store looked at me like I had a third arm growing out of my ass when I said I had not done that yet (tested wires and inspected plugs today all ok based on line resistance)



*Cleaned MAF (needed it but didn’t help much/at all)



*Test TPS, coil pack, and HO2 sensors (all ok)



*check vacuum lines, replaced one and the rest don’t appear to have any major issues


#2

The next thing to check is if there’s a mechanical problem with the engine. Have you’ve performed a compression test?

Tester


#3

nope, haven’t done a compression test. excuse my ignorance but is the compression test going to tell me anything that an amateur mechanic will be able to handle or should I just hand the keys over?


#4

Get an engine compression gauge. Remove all the spark plugs. Remove the fuel pump fuse/relay. Screw the compression gauge into one of the spark plug holes. Hold the throttle wide open and crank the engine over. Note the reading on the compression gauge. Do the rest of the cylinders. If the compression readings between all the cylinders is within 10% of each other the compression of the cylinders is acceptable. If one or more of the cylinders is not within that 10% range, that can cause a miss.

Tester


#5

The fuel injectors might need attention.