TJ seems to burn through coil packs

[MoonShadowTJ]

My ‘01 TJ Sport 4.0 seems to burn thru Coil Packs lately. My TJ started rough idle after start following a 20+ minute stop after warming up and NO codes. Usually it would smooth out and drive great. Cold startups were perfect. One thing of interest is the 4.0 engine runs very hot. The hood will get quite hot after a trip. However the hot start misfire issue worsened so I replaced the CP. I purchased a new one from Amazon by AA Ignition because they offered a 2 year warranty. The first on lasted about 2 months and started misfiring on restart after warmup. Finally I got a Check Engine light and a reader said the misfire was on the #3 cylinder. I contacted AA Ignition thru Amazon and after a couple rounds of texts they sent me a replacement. It’s been installed a couple of weeks. Unfortunately today the misfire started again. I believe this might be a heat related issue as the misfire only happens after a short stop after the engine fully reaches operating temp.

As an aside, I’ve even considered adding vents to the Hood.

What’s the collective wisdom.

 

[taylormade73]

Is your number three injector insulated with heat wrap? There is a heat soak issue you on that injector.

 

[JKP]

Your hood is hot because most TJs don't have an insulating pad on the underside.

Your temp gauge should be running right at 210.

Never heard of AA Ignition. Probably Chinese junk, but I don't know that for certain.

For a coil, I would only recommend MOPAR, and even some of their parts for TJs are now questionable, or Blue Streak by Standard Ignition. 2 yr warranty on the MOPAR and lifetime warranty on Blue Streak.

 

[Jerry Bransford]

Length of warranty is no indication of quality. Some of the very cheapest and least reliable parts come with lifetime warranties, like Duralast from Autozone includes. I'd try to find a Mopar or at least a top quality replacement. The only ignition coil that has ever failed on me was an aftermarket. I'd buy a Mopar ignition coil with only a 12 month warranty before I'd buy an aftermarket with a lifetime warranty.

 

[JKP]

True, but MOPAR coils for the YJ and TJs with distributors are now Chinese junk. Burned through 2 of them, with one being a warranty replacement. The original MOPARS were made in Japan. Even the MSD for the YJ was Chinese.

The Blue Streaks are made in Poland. Only coil I got to work for any length of time on the YJ.

I don't know if the MOPAR TJ rails are now made in China or not, I just went with the Blue Streak based on my YJ experience.

And yes, any of the house brand coils are complete junk regardless of warranty.

 

[Bcrez]

True, but MOPAR coils for the YJ and TJs with distributors are now Chinese junk. Burned through 2 of them, with one being a warranty replacement. The original MOPARS were made in Japan. Even the MSD for the YJ was Chinese.

The Blue Streaks are made in Poland. Only coil I got to work for any length of time on the YJ.

I don't know if the MOPAR TJ rails are now made in China or not, I just went with the Blue Streak based on my YJ experience.

And yes, any of the house brand coils are complete junk regardless of warranty.

running this for about a year with no issues. https://www.ksuspensionfab.com/store/p149/TJ/LJ_Viper_Coil_Mod.html#/

 

[Jerry Bransford]

running this for about a year with no issues. https://www.ksuspensionfab.com/store/p149/TJ/LJ_Viper_Coil_Mod.html#/

That's about how long my Accel ignition coil lasted, the one I mentioned above that failed out in the middle of the desert. Fortunately someone in my wheeling group had a spare Mopar ignition coil he gave me.

 

[Bcrez]

That's about how long my Accel ignition coil lasted, the one I mentioned above that failed out in the middle of the desert. Fortunately someone in my wheeling group had a spare Mopar ignition coil he gave me.

Now I have something to worry about.

 

[MoonShadowTJ]

Great replies! I’ve got to look into insulating the #3 injector. If that works I can go back to my original morpar coil pack.

 

[Jerry Bransford]

Great replies! I’ve got to look into insulating the #3 injector. If that works I can go back to my original morpar coil pack.

This is the part specified by Jeep for the TSB to fix the #3 injector heat sink, it is held wrapped around the injector with a small zip-tie. https://www.amazon.com/gp/product/B007O3QHDK/?tag=wranglerorg-20

 

[CharlesHS]

That's about how long my Accel ignition coil lasted, the one I mentioned above that failed out in the middle of the desert. Fortunately someone in my wheeling group had a spare Mopar ignition coil he gave me.

Last year I purchased a Viper Coil kit with RIPP spark plug wires just to perform a test on reported performance gains.
No performance gains !!
The problem I had with the Viper Kit was with the RIPP supercharger wires where the spark plug clips come loose from the wires (not crimped correctly) and the boots split after 6 months of use causing bad arcing to ground.

The kit is sitting in a box since I am still waiting for replacement spark plug wires after 7 months.

 

[Jerry Bransford]

RIPP low resistance plug wires won't boost performance for a couple reasons. First, the OE Mopar coils provide WAY more spark voltage than is required to reliably combust the fuel mixture. A little more voltage isn't going to help anything there.

Second, the low resistance doesn't significantly boost the voltage. The reason being having to do with Ohm's Law. There is very little current flowing through spark plug wires which means even the high resistance of standard ignition wires doesn't cause a significant voltage drop. Ohm's Law is E=IxR. If I (current) is low, as it is, it's not going to multiply the resistance (Ohms) enough to cause E (the voltage drop) to be significant.

Low resistance ignition wires sounds good in to the average guy but it's really just a rip-off. It actually costs more $$$ to make wiring high-resistance ignition wiring which is needed to reduce ignition noise/static. It costs far less to make low-resistance wiring yet they charge more for it. "Low resistance" spark plug wire manufacturers are laughing all the way to the bank.

 

[CharlesHS]

I didn’t plan to run the kit permanently; I was conducting the test for a year to settle the discussion on whether the Viper coil and RIPP wires would provide any performance gains.
After almost a year I confirmed there were negligible gains.

 

[MoonShadowTJ]

i have noticed the heat insulation around the fuel rail is in bad shape so I'm thinking of replacing all of it.

This is the part specified by Jeep for the TSB to fix the #3 injector heat sink, it is held wrapped around the injector with a small zip-tie. https://www.amazon.com/gp/product/B007O3QHDK/?tag=wranglerorg-20

View attachment 364903

This kit includes heat wraps for all the injectors. Although different wouldn’t this work too? I found a much cheaper price ($43) on eBay. Same maker.

 

[Cross-Threaded-06TJ]

i have noticed the heat insulation around the fuel rail is in bad shape so I'm thinking of replacing all of it.


This kit includes heat wraps for all the injectors. Although different wouldn’t this work too? I found a much cheaper price ($43) on eBay. Same maker.

View attachment 365170

I suggest the Mopar Fiber glass boot for #3. AND that kit you have pictured. I did this same repair on mine to resolve a summertime hot misfire for cylinder 3. It worked.

The fiberglass boot alone may have resolved it. But I wanted to throw a little more at it. The kit looks great installed. I also ran 2 heat shields stacked on top of each other, a new Mopar shield and the DEI one. Unnecessary I'm sure, but it made me feel better.

Below is mine after these parts

 

[MoonShadowTJ]

I suggest the Mopar Fiber glass boot for #3. AND that kit you have pictured. I did this same repair on mine to resolve a summertime hot misfire for cylinder 3. It worked.

The fiberglass boot alone may have resolved it. But I wanted to throw a little more at it. The kit looks great installed. I also ran 2 heat shields stacked on top of each other, a new Mopar shield and the DEI one. Unnecessary I'm sure, but it made me feel better.

Below is mine after these parts
View attachment 365172

Super info! I like your thinking. Thanks again!

 

[bucky]

I’ve bought from K Suspension with no issues. Earlier this summer I bought injectors, injector pigtails and an insulation kit from them. I have not got around to installing them yet. I have the #3 injector code myself.

 

[Moglocker]

I’ve bought from K Suspension with no issues. Earlier this summer I bought injectors, injector pigtails and an insulation kit from them. I have not got around to installing them yet. I have the #3 injector code myself.

I have the k viper kit,I didn’t trust the cheap coil and switched to a blue streak coil,all is good I also have a better set of wires to go on when it’s time for plugs

 

[Jezza]

I put an actual Mopar Viper coil and Viper wires on one of my Jeeps during a dyno session. It made absolutely no difference at all. Not one horsepower change.

 

[Moglocker]

I put an actual Mopar Viper coil and Viper wires on one of my Jeeps during a dyno session. It made absolutely no difference at all. Not one horsepower change.

No horsepower gain at all,just cheaper easier to find replacement coils from here on out(I know they don’t go out often)I did get the new free reinforced bracket from them.I like the idea of old school wires