Misfires on 2 and 3 at 50+Mph
01-20-2013, 09:56 PM
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Misfires on 2 and 3 at 50+Mph I am getting misfires counted on cylinders 2 and 3 at 50+mph nothing below that really. Could this be computer related or crank sensor maybe? Its just strange that for the most part I can only get it to count like 10 misfires if I punch it going below 50. Above 50 it starts misfiring into the 1000's but I don't feel it at all and the car has plenty of power... any clues? I have Hp-tuners that's how I can see it. Only throwing p0300 code.
01-20-2013, 10:02 PM
#3
What gear are you in when it's missing at 50? Is it better/worse in different gears at the same speed. Using a higher gear puts more stress on the engine and will show a misfire that's sometimes not seen during other conditions.
An example of this is I was working on a 2008 MKZ a few weeks ago. It would only miss with the cruise control on going up a hill. The extra load on the engine at lower RPM's was stressing a weak coil out. Normal driving the car wouldn't miss.
An example of this is I was working on a 2008 MKZ a few weeks ago. It would only miss with the cruise control on going up a hill. The extra load on the engine at lower RPM's was stressing a weak coil out. Normal driving the car wouldn't miss.
01-20-2013, 11:11 PM
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Ohh I forgot here is what I have done:
Replaced/swapped : coils, plugs, wires, injectors, O2 sensors (plugs all looks the same and none are fouled.
Replaced: Intake manifold gaskets. (when I did this I checked the manifold and the map sensor both looked fine also cleaned all the ports and looked at the intake valve on each cylinder both looked fine / same as the others.)
Checked for: Vacuum leaks (found none) , a dirty maf (wasn't but cleaned anyways) , compression.
So far nothing has helped and all I have now is a p0300...and a misfire on the same 2 and 3 cylinders no matter what I do.
Replaced/swapped : coils, plugs, wires, injectors, O2 sensors (plugs all looks the same and none are fouled.
Replaced: Intake manifold gaskets. (when I did this I checked the manifold and the map sensor both looked fine also cleaned all the ports and looked at the intake valve on each cylinder both looked fine / same as the others.)
Checked for: Vacuum leaks (found none) , a dirty maf (wasn't but cleaned anyways) , compression.
So far nothing has helped and all I have now is a p0300...and a misfire on the same 2 and 3 cylinders no matter what I do.
01-20-2013, 11:44 PM
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The guy said 30k ish when I bought it but who knows for sure. Weak springs on both with both of them going bad around the same time you think?
01-26-2013, 12:41 AM
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Changed the tune in the misfire table and the misfire moved cylinders what does this mean is causing them (if they even exist since power is fine and I can't feel them at all).