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High Ohms At Coil/Misfire

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Firegst

10+ Year Contributor
94
1
Aug 29, 2012
Queen Creek, Arizona
Ok, So I am having a slight misfire at idle that I can hear and feel. If I drive the car more than say 30 miles the CEL will come on and in Link it says its a cylinder 3 misfire...I can also feel this mis if I am at say 2500rpm in second going down my street the car kinda wants to buck.

So I replaced the plugs(brp7es NGK) and wires(Bosch) and gaped the plugs to .30'
Tested the coils and got 1.1 ohms at the primary and 14.7-14.9 at the secondary...on both coil packs.

New Front 02 no boost or vaccum leaks either.

(I TESTED THE COILS BEFORE AND I DID GET SIMILAR NUMBERS TO THE ABOVE, BUT I USED AUTOZONE'S WEBSITE FOR THE SPECS AND THESE WERE OK, AFTER LOOKING ON ALL-DATA FOR FACTORY SPECS THIS SEEMS NOT TO BE THE CASE- OEM IS .70-.86 AT THE PRIMARY AND 11.3-15.3)

My question is could this high ohm reading be causing my mis at idle? I would think that if it were a coil pack issue that I would be getting the mis-fire on cylinders 3 and 2 being that they are coming from the same coil. Also could the out of spec primary cause this issue? If so why only on one cylinder? I have move the plugs around, and the wires, the miss doesn't follow.

Has anyone else had this issues with high ohm readings for the primary? Hoe could the mis-fire be on just the third cylinder if it were a coil pack related issue? I am stumped, thanks in advanced for any help.
 
The ignition transistor check out as well as the resistor box I have also swaped out injectors with no change.also I have swaped out coils twice. They had the same primary ohm spec around 1.1....could all three coil packs have been bad or do I have a different issue
 
These types of problems can be near anything and so are hard to find. Some ideas:

AllData is correct with their coil specs so yours are a little high. Higher resistance results in less maximum primary current in coil which gets less secondary voltage for the plugs. Slightly higher resistance usually isn't a big problem but perhaps yours are right near the edge since cyl 3 has a longer spark cable than 2 and only 3 misses, not 2. Can you replace cyl 2 cable with a longer one than 3 just for test purposes to see?

Or the PT doesn't have a solid ground (the case bottom is also ground and must be bolted to the head).

Or perhaps cyl 3 injectors are somewhat faulty.
 
These types of problems can be near anything and so are hard to find. Some ideas:

AllData is correct with their coil specs so yours are a little high. Higher resistance results in less maximum primary current in coil which gets less secondary voltage for the plugs. Slightly higher resistance usually isn't a big problem but perhaps yours are right near the edge since cyl 3 has a longer spark cable than 2 and only 3 misses, not 2. Can you replace cyl 2 cable with a longer one than 3 just for test purposes to see?

Or the PT doesn't have a solid ground (the case bottom is also ground and must be bolted to the head).

Or perhaps cyl 3 injectors are somewhat faulty.

Everything is grounded, The cables have been switched and I have new injectors.

The misfire has went from cylinder three to just a random misfire now code 0300. I did swap out too other coils from running cars and they were at the same specs as mine.. Could this be a tune issue?
 
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