Strange Misfire

[davidp94]

Before I start I would like to thank anyone in advance for posting. This has been quite the bothersome issue. Let me explain:

- cylinder #4 dead.
- coils good, sparks good, injectors good, code 55 (no malfunctions in the codes our computers check for)

I know the coil is good because i swapped the suspect bad coil pack into another cylinder and that cylinder fires no problem. I know the injector is firing because I can hear it (screwdriver method). So I narrowed it down to cylinder #4 b/c when i unplug the coil pack connector I notice no decrease in performance like I would if i did the same thing on any other cylinder bank.

The reason why I've titled this post as "strange" is because the misfire is only noticeable up to 3000 revs. After 3000 rpm it seems as if the misfire is nonexistent. What should I do?

[Ziggy1621]

Have you Ohm'd that injector?

[davidp94]

Yes I have. She's within spec according to the FSM

[solaire]

What does that cylinder's plug look like? Is it wet with fuel? Also have you run a compression check yet?

[davidp94]

I have not yet done a compression test. To check if it is wet with fuel I just run the car and then pull the plug right? Of course with the car off. If it is wet that indicates the injector is working??

[solaire]

wet indicates it's either 1: not sparking, bad coil or ptu connectors. This can be checked by placing coil on intake and see if it makes a nice blue spark. If no spark or orange spark check ptu connector for corrosion. 2: injector is stuck open or 3: no compression to ignite the fuel.

[davidp94]

I take the coil and put it on the intake? I should be looking for a spark shooting out of the bottom?