Need help with my 2007 Wrangler unlimited (misfire issues)

[jeep78]

Great information. I'll try this tomorrow or Thursday. Do I have to order a pre-programmed pcm, or get it programmed by a dealership?

PCM=computer in my post, sorry for confusion.

you will need a computer specific for your model/engine/tranny combination.

 

[grandall1972]

Again though, thanks for the input so far. The ODT continues to prove why it's one of the best forums on the internet. Great people, fun toys, and people care enough to give input. I posted the same question on the wrangler forum and have one reply.

Thanks again ODT.

 

[grandall1972]

PCM=computer in my post, sorry for confusion.

you will need a computer specific for your model/engine/tranny combination.

Yeah, I've figured that one out. I can order one set up for my VIN number for just under $400. Going to check and see what my preferred dealer says first. Ed Voyles cdj, but I normally only deal with their diesel guys, and they are great.

 

[jeep78]

Those computers are pricey. Try to eliminate other causes before just trying a computer.

 

[jeep78]

Do you have access to a high quality OBD scanner? Mine has a real time monitoring mode. There is also an app for smart phones called torque that does pretty much the same thing, it uses a bluetooth dongle for the OBD port. Also can connect to a laptop. Lots can be learned diving into what the computer is actually doing and seeing, far more than just the codes.

If you plan to keep with working on computer controlled vehicles, these items have become a must have.

 

[Widow maker]

If your getting fire to all plugs clean the throttle body a dirty throttle body can cause what we mechanics call a ghost misfire. If there is no fire then I would check on the ecu it will have to be programmed if you get a new one . A crank sensor will cause a misfire but usually get a code for it or cam sensor. All you have to do to clean the throttle body is a rag and carb cleaner open the butterfly up and clean the carbon build up inside . This is a common overlooked problem that mechanic shops don't like to reveal. Hope that helps

 

[grandall1972]

Do you have access to a high quality OBD scanner? Mine has a real time monitoring mode. There is also an app for smart phones called torque that does pretty much the same thing, it uses a bluetooth dongle for the OBD port. Also can connect to a laptop. Lots can be learned diving into what the computer is actually doing and seeing, far more than just the codes.

If you plan to keep with working on computer controlled vehicles, these items have become a must have.

That's probably worth investing in. I've always been an older car guy, but building a 4 door jk for the family kills three birds with one stone. I get to enjoy a hobby, my wife loves jeeps, and it fits the kids easily.

 

[grandall1972]

If your getting fire to all plugs clean the throttle body a dirty throttle body can cause what we mechanics call a ghost misfire. If there is no fire then I would check on the ecu it will have to be programmed if you get a new one . A crank sensor will cause a misfire but usually get a code for it or cam sensor. All you have to do to clean the throttle body is a rag and carb cleaner open the butterfly up and clean the carbon build up inside . This is a common overlooked problem that mechanic shops don't like to reveal. Hope that helps

Yeah, throttle body is clean, and there is no fire at all on cylinders 3, and 6. I'll probably end up ordering one that comes preprogrammed tomorrow. Just wish I could get it back tomorrow. I hate waiting. I have a new toy and I want to play with it. (Just kidding, but I do prefer same day service)

 

[Widow maker]

I know the feeling that is more than likely your culprit though hit me up if it don't fix the problem

 

[grandall1972]

I know the feeling that is more than likely your culprit though hit me up if it don't fix the problem

Thanks. Will do.