Cyl 3 misfire...Am I on the right track?

[TheveryunreliableRanger]

I have an 03 Ranger 3.0L XLT. I bought it about 9 months ago from an older couple with about 65k miles on it.

Alright, so I got the code for a cylinder 3 misfire. I noticed it was skipping & lacking power during acceleration. I checked the oil & it was dry. I did an oil change with 5W-20 Full syn penzoil.
No difference in symptoms.

Kind of went high & right & changed a camshaft position sensor & synchronizer. Didn't work.

Hooked up a spark plug tester & all 6 cyls are getting spark.
Removed all 6 spark plugs, they don't look bad, but none of them read any continuity. Really odd but didn't also care because I'm going to change them all out anyways.
Read resistance on cyl 1 2 & 3 fuel injectors they all read 16 ohms. (Was hoping for #3 to be OL)
Did a dry compression test & they read as follows:
Dry compression test:
Cyl 1: 185
Cyl 2: 185
Cyl 3: 180
Cyl 4: 160
Cyl 5: 170
Cyl 6: 185
Wet compression test round #1
Cyl 1: 200
Cyl 2: 200
Cyl 3: 210
Cyl 4: 205
Cyl 5: 170
Cyl:6 190

If I take 185 & multiply by .15 I get 27.75.
185-27.75= 157.25. My weakest cly can't be under that 157#. Cyl is VERY close. Then doing a wet compression test & it's #s spiking up tell me it's the lower end seals that need replacing. Might as well do all the seals right?
I'm going to send it into a shop if my changing out the spark plugs & fuel injectors doesn't fix the misfiring issue.
If it does fix the issue, I'm still sending it into a shop to get those lower end seals replaced. While they've got her all torn up, is there anything I might as well have them do in order to keep her running strong for years>

I'm thinking OEM motorcraft fuel injectors & dbl platinum for spark plugs.

Any recommendations would be great. Thanks!

 

[rusty ol ranger]

It takes 3 things to make a cylinder fire.

Fuel, spark, and compression.

Youve obviously got spark, your compression seems decent, so now youre down to fuel.

My guess is you got a sticky injector. Disable the ignition system (pull coil wire or unplug coil pack) and crank the engine over, pull the plugs. They should be pretty uniformly wet with gas.

My guess is the #3 plug is going to be dry or dryer then the rest.

 

[Uncle Gump]

With the compression numbers you have... no way I would be sending it in for a rebuild. The lower end seals you talk about would be the piston rings... to replace those... you're looking at an engine rebuild.

With the mileage it has... I would install a good set of plugs. Put it back together and try running a tank of fuel with seafoam and see if it will clean the injectors.

 

[TheveryunreliableRanger]

With the compression numbers you have... no way I would be sending it in for a rebuild. The lower end seals you talk about would be the piston rings... to replace those... you're looking at an engine rebuild.

With the mileage it has... I would install a good set of plugs. Put it back together and try running a tank of fuel with seafoam and see if it will clean the injectors.

Okay so I'm thinking new spark plugs just cause they're already out & idk when the last owner did a swap, new injectors, seafoam, & if she runs great then let it be.

 

[Rearanger]

Switch ignition wires if you can and see if misfire moves also.

 

[TheveryunreliableRanger]

Alright every I know we've all been waiting for an update...so I ended up changing out sparkplugs & fuel injectors..After installing everything she was clear of her misfire! Misfire codes disappeared praise baby Yoda. Now, I have 2 codes for Lean in Bank 1 & Bank 2. So I'm thinking damn I removed & reinstalled the upper intake manifold so I must of not sealed it right. But everything I'm reading is saying that because it's in BOTH banks 1 & 2 this is very far fetched. So, now I'm thinking it's a vacuum line that is old OR OR OR I possibly installed the wrong fuel injectors (let's say one for a 03' 3.0L gas instead of mine which is FFV). So I wiggled all the vacuum lines & spray starter fluid on them all, no reaction in rpms from the motor. The difference in injectors COULD be what's not delivering enough fuel to the air mixture.
Thoughts? I'm about to take it to a shop because I've got too many other tasks going on.

 

[4.0blue98]

When I had a 171 and 174 that would come and go on my 4.0L OHV, it was the upper intake manifold (plenum) gaskets. Changed them and codes never came back. If you pulled the manifold and didn't replace the gaskets, then that could be you issue.