Missfire

I have a taco 05. I just changed airfilter sparkplugs and just yesterday coil6.
So to make a quick diagnostic I switched cylinders coil 4 to 6
And it still called for missfire on 6 as to why I changed the coil but it still little jumpy and I have a feeling that it may turn on check engine again. Any suggestions to diagnose it better

 

How many miles do you have on your truck? And its the 4.0 v6 im assuming?

I would start by having the codes pulled whenever it is misfiring.

05-06 v6 trucks are notorious for a head gasket design flaw. The head gaskets usually go on cylinders 5 and 6

 

Did it have the misfire before you changed the plug, or after. If only after, try a different plug. Last time I did mine on my old '12, the #1 plug had a hairline crack that you could only see once it started arcing, and even then it was hard to see. Swapped another plug in and it was golden.

 

It was reading missfire before I changed the plugs. Then it came back so I switched them around
But then it read it again so I just bought a new one and installed it but it's a little jerky. No light yet tho

 

Its is a v6 4.0 it has around 178k but no problems elsewhere. It read missfire on c6 every time the light would show

 

So the problem existed before, persists with a new plug and coil pack, persists with coil pack moved around. So spark should be good. A problem with air would likely move around. So you could try some injector cleaner or a new injector to rule out fuel, but unfortunately I agree with @rjbiii, you probably need to rule out the head gasket. You can have your coolant checked, and if negative, should probably still have compression checked.

Does it go through coolant, even really slowly?

 

I did do an injector cleaner after the plug change
Never had to add coolant temp is steady

 

How do the wires look going to the coil pack, and what shape is the connector in? That is probably the last thing to check on the spark end of things.

Injector cleaner isn't going to fix a faulty injector, only *possibly* clear it of any clogs. But it's cheap and worth a shot, and you tried it already. A remanufactured injector is $50 if you feel like trying that, not sure how involved that is on a 4.0.

But the principle is simple -- suck, squeeze, burn, blow. Gotta have air and fuel sucked in, gotta squeeze it, gotta burn it, gotta blow exhaust out.

I would get the checks done to make sure the squeeze part is getting the job done. Even if it's not the head gasket, you could have a valve issue.

EDIT: Even if it's not going through coolant and it's running normal temps doesn't necessarily mean the head gasket is OK, that's just a sign. Look under the radiator cap for a milky substance.