Need some help diagnosing misfire codes on a 2006 Rubicon

AndyG

AndyG

Because some other guys are perverts
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Goal has been to just make this Jeep great and essentially tune up the engine after 135,000 miles of driving with a suspected “only fix what breaks “ maintenance history-


Has a new @Wranglerfix pcm, new plugs, new cats, all new NTK/NGK 02 sensors-

Ran flawless for a short while- now gets a rough idle when hot , now throwing multiple codes-

2096, 2098,300 , TCM showed 218 degrees was a warning my scanner showed this pm

What I know-

The number 3 injector sounds distinctly different -

Live data shows my Bank 1 Short term fuel trim at 99.5 percent, so the computer is trying to compensate for something- richening up the fuel -

Is it possible I have a bad injector at the heart of this and do these things have map and maf sensors and will they code specifically -

Basically it runs good until it doesn’t

@Jerry Bransford I echo your reservations about 04-06 models, every one I’ve had has codes/ engine management drama-

Happy 4th guys - America is great because it it good. Good values made this nation what it is .

Andy G
 
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Stay tuned- may have found the problem- and it’s something I had no idea was possible- the #3 injector plug sleeve had rotated and was laying on the heat shield/manifold - hot hot hot

Got a fan on it now and going to clear the codes -

This may explain a lot
 
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Well gang, of all injectors to get too hot, ol’ number 3 was getting the wires cooked on the heat shield- it was throwing out codes like a building inspector in shantytown-one zip tie and she is back at about 11 o’clock secured to the throttle cable bracket- now to insulate it.

Had occasional rough idle when hot , knocking, multiple codes-

Smooth as silk now. Time to check the 03 connector orientation-

For the record guys those things seem to be a friction fit or the heat loosens the sleeve- be good to watch your injector plug orientation

In the process I got a good scanner and have been learning a lot about fuel trim and 02 data- simply put carburetors don’t stand a chance against fuel injection- the computer is constantly taking data and giving the perfect amount of fuel and air for the current demand - it is so far beyond what a carb does there is absolutely no comparison- all the while stabilizing the fuel under pressure. It is likely the biggest automotive advancement in the last 40-50 years -
 
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AndyG said:
Well gang, of all injectors to get too hot, ol’ number 3 was getting the wires cooked on the heat shield- it was throwing out codes like a building inspector in shantytown-one zip tie and she is back at about 11 o’clock secured to the throttle cable bracket- now to insulate it.

Had occasional rough idle when hot , knocking, multiple codes-

Smooth as silk now. Time to check the 03 connector orientation-

For the record guys those things seem to be a friction fit or the heat loosens the sleeve- be good to watch your injector plug orientation

In the process I got a good scanner and have been learning a lot about fuel trim and 02 data- simply put carburetors don’t stand a chance against fuel injection- the computer is constantly taking data and giving the perfect amount of fuel and air for the current demand - it is so far beyond what a carb does there is absolutely no comparison- all the while stabilizing the fuel under pressure. It is likely the biggest automotive advancement in the last 40-50 years -
Click to expand...

Carbs do not do well going from sea level to 13,000 for sure.
 
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So, did this turn out to be one of those innumerable alleged 04-06 maladies?

Or something that could happen to the broader population?

I have an 05 ljr and haven't had any issues aside from some difficulty with aftermarket cam position sensors and reverse on the nsg370.

Since it's a manual trans, I'm immune to the pcm issues some experience with the auto
 
g.hayduke said:
So, did this turn out to be one of those innumerable alleged 04-06 maladies?

Or something that could happen to the broader population?

I have an 05 ljr and haven't had any issues aside from some difficulty with aftermarket cam position sensors and reverse on the nsg370.

Since it's a manual trans, I'm immune to the pcm issues some experience with the auto
Click to expand...

We just had @Wranglerfix furnish a PCM in for a 2006 LJ Manual- just sayin-

On a sidenote I was spending a lot of time thinking about the late model ones- It is really reminiscent of 1985 when Jeep was trying to keep the CJ-7 compliant with government mandates or whatever the goal was- It had a worms nest of vacuum hoses -

I think the 258/4.0 was simply kept in production so long that they struggled with the engine management needed to keep it in the modern era-
 
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AndyG said:
We just had @Wranglerfix furnish a PCM in for a 2006 LJ Manual- just sayin-
Click to expand...

What problem was fixed by replacing the PCM?

If your new PCM actually fixed a problem on a manual trans tj, it might be the 1st account I've read about.

Certainly, pretty rare
 
g.hayduke said:
What problem was fixed by replacing the PCM?

If your new PCM actually fixed a problem on a manual trans tj, it might be the 1st account I've read about.

Certainly, pretty rare
Click to expand...

Stalling when running -

The owner/ Jeep came from California, moved here and he took it to Cole’s Auto Repair, an ace guy in town I’m friends with - I was there and saw it and asked why he had it - he told me, we asked Mark @Wranglerfix what he thought and he agreed, sent a unit and it fixed it -

Mark will know for sure how common it is with manuals-He sees way more from his end.
 
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