Misfires dont know where to go

[jkbwd2]

alright i changed my spark plugs,spark plug wires,air filter,distributor cap and rotor but still has a misfire. Also when i pulled the spark plugs the threads were lightly covered in oil so im not sure what to check next so if someone can help me in the right direction that would be great

[87hilux7mge]

are you sure this is a "misfire" and not a straight up "miss"? a misfire would indicate improper timing of some sort.

im gonna assume you have an N/A, cuz of the cap and rotor comment. check to see if your cap is cracked, has moisture inside, if wires are faulty etc. even new stuff can be bad.

next, if you have oil on your plugs, how much? if its alot, might be a bad valve seal. a compression check and leak down test could help identify where the oil is coming from and if its enough to cause the misfire.

fuel system would be next on my list, checking to see if an injector is opening/closing, etc.

post back with some more info, try to help ya as much as possible.

[jkbwd2]

ya so i took it to one of my buddys shops and he found 2 vacuum leaks one on top of the throttle body on that plate that i don`t know why its there and the other was going from the throttle body to i believe the intake (the hard black tube. Since that i got rid of my hesitation problem when i get on it sometimes but I`ve still got a misfire from somewhere i changed cap and rotor,new spark plug wires,spark plugs etc. I know it cant be a ignition misfire its gotta be a fuel misfire or something still unsure where to look next

[jkbwd2]

plus i believe i need new valve seals cause its not necessarily quenched in oil but its got a medium coat on it

[87hilux7mge]

sounds like you have a fuel misfire to me. but before i jump the gun, make sure you check spark for all cylinders.

do this by taking the spark plugs out, connecting one at a time to each spark plug wire, grounding the spark plug tip and cranking the motor (they also sell spark testers at your local chain auto parts store, this is much safer and they are only a few bux usually). you should get a strong blue spark from each plug.

if you have strong spark, on all cyls, then id lean toward a bad injector seal, or injector clip. you can test the voltage reading from the injector clip and the resistance of the injector itself.

i dont have the link to cygnus on hand, but a quick search should reveal it.

good luck, hit back with any results!