misfire after installing new cap and rotor
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From: Clayton MI
does the misfire happen all the time? during regular acceleration too?
Seems like things were just fine before you replaced the cap and rotor -- I wouldn't dig too deep until you figure out the rotor and cap are ok.
IIRC when I replaced my rotor and cap on my 5.9L I also changed a simple and cheap sensor below the rotor - that came recommended from this forum - maybe a crank position sensor?? Hopefully someone else can chime in.
Seems like things were just fine before you replaced the cap and rotor -- I wouldn't dig too deep until you figure out the rotor and cap are ok.
IIRC when I replaced my rotor and cap on my 5.9L I also changed a simple and cheap sensor below the rotor - that came recommended from this forum - maybe a crank position sensor?? Hopefully someone else can chime in.
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From: NH
It's the truth and NOT worthless there bud. You had to move the wires quite a bit to uninstall and install the new cap and rotor. Ohm's mean nothing when the truck is running and there is now a potential crossfire that may have not been there before.
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Joined: Apr 2010
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From: Clayton MI
Ah, so, it's entirely possible the two events are completely unrelated.....
Only misses under hard acceleration? If it were the other way, I would suggest the O2 sensor... but, at large throttle openings, PCM ignores the O2 sensor......
Take it for a ride, and drive about 45 MPH....... if you have a consistent miss, it WILL show up there..... If that's nice and smooth...... maybe a cracked plug?
Only misses under hard acceleration? If it were the other way, I would suggest the O2 sensor... but, at large throttle openings, PCM ignores the O2 sensor......
Take it for a ride, and drive about 45 MPH....... if you have a consistent miss, it WILL show up there..... If that's nice and smooth...... maybe a cracked plug?
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HeyYou thanks. I am probably just gonna bite it and put plugs, wires and coil in it. Hope this doesn't get expensive changing parts.
Zman17, A single comment does not help. If you know something by all means post it. I am not a mechanic by any means, if I were I wouldn't be on this site asking for help. I am trying to track down a problem without spending a ton of money that I don't have. I understand the cross fire issue but I also know if the wires don't have the proper ohms then they are broke down and won't carry the pulse to the spark plug.
Zman17, A single comment does not help. If you know something by all means post it. I am not a mechanic by any means, if I were I wouldn't be on this site asking for help. I am trying to track down a problem without spending a ton of money that I don't have. I understand the cross fire issue but I also know if the wires don't have the proper ohms then they are broke down and won't carry the pulse to the spark plug.
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From: NH
Ok no problem, lets all calm down. 
The inside of the plug wire can be fine and ohm correctly, but if the casing fails you get crossifire between wires or if one is too close to something and worn or cracked. In other words, the spark can jump out of the wire through the casing. Seems to me, if it was fine before, then something got moved or damaged. Vac line crack, the wires for both the crank and cam sensors are right there too.
The inside of the plug wire can be fine and ohm correctly, but if the casing fails you get crossifire between wires or if one is too close to something and worn or cracked. In other words, the spark can jump out of the wire through the casing. Seems to me, if it was fine before, then something got moved or damaged. Vac line crack, the wires for both the crank and cam sensors are right there too.