Topic: 3.4 misfiring

[toyofan7987]

my 97 t100 3.4 keeps throwing a code. cylinder 2 misfire. have changed oil spark plugs and the coil and its still doing it??? any idea?

[yotaneck13]

un hook battery unplug ecu let it sit overnight then try it see if it resets if it does not pull the spark plug and check to see if the gap  is correct also did u replace the coil pack its self or just the wire running from no 1 to no2?

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check your 02 sensor.

[yotaneck13]

o2 wont make a misfire cide trip i dont even run my o2's and it runs fine

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some times if they are really fouled up they do missfire and sound like a wrx. I'd check your coil packs also. And grounds.

[Offroadassassin]

My truck is doing the same thing . i replaced spark plugs, the plug wires, and the coils. let me know if you figured yours out
 

[E YOTA]

there might be water leaking into that cylinder, thats wat happened to mines...are u losing water too...jus a little bit at a time

[Offroadassassin]

No water in the oil. or does that matter? i dont think im loosing water. If thats the problem , what needs to be replaced?
 

[superkaliguy]

this happen to me a while back in my 97 t100 too, i had a bad valve. I replaced it and it turn out fine afterwards

[spuds015]

swap the stick coil that has the cyl 2 plug wire with another one, if the code moves to the new cylinder, its a coil. if not its either compression or fuel. i have same issue but on #6. new plugs new wires on mine, coils are good. compression is adequate for 236k miles so injector is only thing left

[Offroadassassin]

swap the stick coil that has the cyl 2 plug wire with another one, if the code moves to the new cylinder, its a coil. if not its either compression or fuel. i have same issue but on #6. new plugs new wires on mine, coils are good. compression is adequate for 236k miles so injector is only thing left

   Thanks,  looks like i need to check the compression next.  i have 191,000 on my 04' love the motor just doesnt have all its power anymore

[Offroadassassin]

Took it to the shop. oouch!   he checked the code,  the history said miss on the 1 cylinder , and was also the reason the check engine light was on.
He took the coil out to do a leak down and compression test. said the coil had a white mark like the spark was grounding past the coil to the head or nearest  ground.
He said the compression was 165lbs. but the receipt says 170 and he tested the injector pulse, all was good.
he said it must have been the coil plug but i had the problem then replaced the plugs trying to fix it.  
Do you think my #1 cylinder will arc out my new coil?
 My truck is running better than it has in a long time. He also did my timing belt, water pump, and thermostat, idler , all my belts and radiator hoese

[spuds015]

shouldnt arc since the coil was replaced, worn/bad coils or sticks can arc.

[Offroadassassin]

   Damn check engine light came back on i bet its the number 1 misfiring

[yotaneck13]

take it back to shop and pregnant dog you jus forked out all thT MONEY and it didnt fix it they have to do it free not! thats bs i would never go back to that shop again after this is resolved :bull crap:

[spuds015]

so did it even run right the whole time with the new coil? betcha injector is going. mine ran right intermittent then stopped on a drive home.