2005 mazda mpv. 2 plugs not firing, resistance test on coils are uniform at 11.53

It sounds like you are still not getting the desired spark in the cylinder. A couple of other things to check are the plug wires and more importantly, check the gap on the new plugs. The gap listed for that year of MPV is 0.054 inches. You local auto parts store should have a gap tool, if you don't have one already. Even if they came pre-gapped, it would not hurt to check and make sure they are within that gap spec. There is also another suggestion to check the cam positioning sensor. If it is not sensing correct, the coil pack won't fire at the correct time.

If the van was running before you changed the wires, I don't see how it is not firing the plugs now unless you got the wrong wires and they are not making contact with the coil towers and the plugs.
If there is no spark on any of the wires, something happened to the coil pack or the crank/cam sensors. Or a fuse or relay for the coil pack.
I would probably try an old plug wire to make sure, then check the coil for voltage.

I'd check #1 spark plug.
Usually a misfire code "fix" is a spark plug, spark plug wire, or a coil pack / distributor.
Keeping it simple...I'd go with the spark plug first and then look at the condition of the wires.

Hope this helps...

I just changed plugs on my 05' you have to remove the intake plentum to gain acsess to the rear plugs. First remove plastic cover from top of engine, remove intake hose to throtle body, unplug electrical connections to sensors on plentum, unhook vaccum lines, there are two coolant lines that need to unhooked from underneth throttle body, remove plentum support bolts, one on back and one on right side towards rear, a flash light and a mirror is useful for locating these bolts, there is also two vaccumn lines on the very back off plentum that have to be removed. remove clip on back off plentum that secures the hose that goes across the side of the plentum. Remove the six hold down bolts on plentum, and remove plentum. Spark plugs are acsessed by removing the coil packs for each cylinder, simply remove each coil pack hold down bolt and remove coil, plugs are underneth coil packs, you will need a long extension and a 5/8 spark plug socket to remove plugs.

Check the spark plug first. then if the plug is good you wil need a digital ohm meter to test the coil pack. if you need to know how to remove the coil pack let me know, to test put on ohms should not have more than 2 1/2 ohms restance betweent coil lead to coil connector. If you test the coil pack on both sides of the pack and get a reading then the coil is bad, if it does not read then you haave a bad fireing plate diode.

Cylinder 4 is misfiring. Take it to a mechanic and have them take a look at it. Im guessing its the distributor, Spark plug, or spark plug wire on cylinder 4

The resistance should be 9.2 but what you have is the voltage reading of 12.94 which is the correct voltage for the coil. Need to unplug the electrical connection not the plug wire and measure the resistance there and see if you have the 9 ohms of resistance. If you do not then replace the coil.

If you have a volt/ohm meter, you may want to first ohm check the resistance between the two spark plug towers on each ignition coil pack. Simply remove the spark plug wires from each coil pack and test. Both (if good) should test about the same resistance, (about 5-7 kOhms, but I don't have the exact specs handy on this particular vehicle. The reading may be higher, maybe around 7-12kOhms) but nonetheless, the reading of the 1-4 coil pack should closely match the 2-3 coil pack. If not, the new coil pack may be faulty and should be returned for a replacement.

Also, when you remove the 1-4 coil pack, take a look at the primary spade connectors (2 lugs) coming out of the ignition module. Make certain these are clean and free of rust or corrosion. If so, simply (and gently) use a finger nail file or 400 (or equivilent) sandpaper to file the corrosion off and re-attach the coil pack.

If one or both of these don't fix the problem, you may have to look at replacing the ignition module. But only do that after exhausting the other simpler and less expensive tests! :)

I hope these tips help you out or at least point you in the right direction! :)

it sounds like the coil pack is bad so go ahead and replace the pack. that should fix your problem

pull of the engine covers if so equipped, the plugs each have there own ignition coil, they are held in position by a single retainer, remove the coils to access the plugs. see photo of coil