Help Need advice
Help Need advice
I have a 2001 Ford ranger xlt 3.0 v6.. i have a misfire in #6 CYl.. i Just changed the ignition coil as well as spark plugs and wires and it still says misfire.. what else could be wrong?? Thanks
What is the code number you are getting?
And is it the only code?
Did you reboot computer after changing coil?
Unhook battery for 5 minutes to reboot.
What did the old #6 spark plug look like compared to the other 5?
A cylinder needs 3 things to fire:
Spark(at the right time)
Fuel(in the right amount)
Compression(above 120psi)
A simple test for fuel is to unplug the coil, you want a no start, and then crank the engine a couple of times.
Pull out spark plug #6 and look if it has fuel on the tip
Also pull out #5 to compare how much fuel should be on the tip.
For compression you need a pressure gauge, remove all spark plugs first, and then test ALL the cylinders, one at a time.
Compression tests are no good unless all cylinders are tested at the same time with same gauge and parameters.
With pressure gauge hooked up
Turn on key and press gas pedal to the floor, this shuts off fuel injectors, crank engine until you hear at least 4 compression strokes, you will know trust me, lol.
Write down cylinder and pressure, clear pressure gauge and move to the next cylinder
And is it the only code?
Did you reboot computer after changing coil?
Unhook battery for 5 minutes to reboot.
What did the old #6 spark plug look like compared to the other 5?
A cylinder needs 3 things to fire:
Spark(at the right time)
Fuel(in the right amount)
Compression(above 120psi)
A simple test for fuel is to unplug the coil, you want a no start, and then crank the engine a couple of times.
Pull out spark plug #6 and look if it has fuel on the tip
Also pull out #5 to compare how much fuel should be on the tip.
For compression you need a pressure gauge, remove all spark plugs first, and then test ALL the cylinders, one at a time.
Compression tests are no good unless all cylinders are tested at the same time with same gauge and parameters.
With pressure gauge hooked up
Turn on key and press gas pedal to the floor, this shuts off fuel injectors, crank engine until you hear at least 4 compression strokes, you will know trust me, lol.
Write down cylinder and pressure, clear pressure gauge and move to the next cylinder
Last edited by RonD; Jun 18, 2014 at 10:00 AM.
P0300 is a Random Mis-fire, so not specific for number 6
P0306 is #6 mis-fire
If p0306 then crank engine without coil and check #6 spark plug for fuel.
If there is fuel on the plug then you will need to do a compression test
P0306 is #6 mis-fire
If p0306 then crank engine without coil and check #6 spark plug for fuel.
If there is fuel on the plug then you will need to do a compression test
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