hey guys, my 99 stang seems to be misfiring, i put a timing light on the coils, but the thing is it wont give me any lights, i figured its because its a differant ignition system so, the questions lies, how do you check for misfires on 99 and up mustangs? Thanks a bunch
I know this is a rather undefinative method, but your MIL should illuminate if you have a misfiring condition. Even one random misfire should be detected and throw the MIL.
a misfire should throw a check engine light. you can also hook up a scan tool and use real time information to moniter for misfires. o, you cant use a timing light on the newer 4.6's with coil on plug. the timing is completely controlled by the computer. when was the last time you did plugs? you might want to go and change out the plugs and change the fuel filter.
I had a mis on my 01 about a month back. Apparently it is pretty rare, but a coil pack went bad. I bought a new one and replaced the old with the new one by one. Replace, drive up street, felt like crap, lather, rinse, repeat as needed. lol.
It was the last one i checked. Btw, they are not cheep. I work at an auto parts place so i got mine for 30 bucks. apparently they reatil for around 100bucks. And it NEVER threw a code.
You can pin point which cyl is misfiring on any car by disconnecting the fuel injectors one at a time. When you disconnect it, you should hear the engine stumble just a bit, if the cyl is working properly and not missing. If you pull an injector and nothing happens, you found your problem cyl. It is then up to you to figure out if its a spark or fuel problem. Do not disconnect the spark plug because this will cause excess fuel to be dumped into the cyl and possibly wash down the walls.
Quote from KenB :worship: over on ModularDepot - "Check for spark. Pull the coil pack off and hold it close to the strut tower (or any ground). Trip the inertia switch in the trunk (to cut off fuel) and have someone crank the engine. You should get a spark jumping from the pack to the ground. Test each COP.
If you have spark on all cylinders, pull the plugs...and see if the plugs are fouled. If they are, I would suspect a bad 02 sensor."
well it turned out to be Numero 7 coil was bad, i figured it out by putting one of the coils from my 04 on it and it happened to be the first one i tryed and it worked, thanks for all the input.