Changing JK fuel injectors to JL fuel injectors

Mike 58218

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I heard you could change your fuel injectors to the JL ones. They have more holes in the injectors. Has anybody did this yet? If so, do you have a part number?
 
JL injectors are cheaper than JK injectors.

I wouldn't dive into the engine just to make this change, but if you were changing anyway might as well go with the JL units. 8 vs 4 hole is directional correct for fuel atomization but agree with @Chris that for our engines you won't see any real benefit. Lower cost is always good, though!
 
Just had an injector fail on cylinder 2 at 80k miles. Since I don’t know where the other injectors stand, I decided to proactively replace all 6. Mopar on Rockauto were $134. Bosch (OE supplier for Mopar) were $47. Looked up the Mopar JL injectors and they were $34 each (Bosch were the same price). Called the local Jeep dealer and they wanted somewhere around $200 per JK injector and $108 per JL injector (MSRP $48). Stupid prices. So, I bought the Mopar JL injectors from Rock auto. Part number 5281427AA. (FedEx…..you suck)

Install was easy. Just take your time and you’ll have no issues. Cleaned everything really good before putting it back together. Used a tiny bit of ATF to lube the orings to reassemble. Some people use silicone grease but I recommend not doing that. Silicone can destroy oxygen sensors.

Verdict….runs great! No more misfire and injector codes (#2 injector had fully failed). I don’t think the engine runs better per se than before when the injectors were working properly but I did notice a small gas mileage bump. I haven’t run it long enough to have a solid number but looks like about 1mpg increase. I usually drive slow so someone who drives harder than I usually do probably won’t see as much of a mpg boost.

So, I wouldn’t replace your old injectors with JL injectors for “performance boost” but when you need injectors (or want to proactively replace them before a trip) the JL injectors are the only way to go. Much cheaper than OE injectors and work a little bit better.

Side note….looking on line I saw some people also replacing the lower intake manifold. I didn’t see a substantial value in replacing it so I didn’t. I don’t regret that decision at all.
 
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I had to replace the oil cooler so at just over 100k I also replaced plugs, injectors with JL style, coil packs, lower intake with new PUG style, belt, tensioner and pulleys. a few weeks prior I replaced hoses, radiator and thermostat.

Idle is much smoother, but that could have been just from the plugs. JL Injectors are cheaper, but do I notice the improved atomization? No. Was PUG needed? absolutely not, but I can and I was curious, so I did.

My observation is the JL Injectors are a better choice simply based on cost.
 
I had to replace the oil cooler so at just over 100k I also replaced plugs, injectors with JL style, coil packs, lower intake with new PUG style, belt, tensioner and pulleys. a few weeks prior I replaced hoses, radiator and thermostat.

Idle is much smoother, but that could have been just from the plugs. JL Injectors are cheaper, but do I notice the improved atomization? No. Was PUG needed? absolutely not, but I can and I was curious, so I did.

My observation is the JL Injectors are a better choice simply based on cost.

Based on cost alone they are the only way to go. Wouldn’t surprise me if a dealer would charge you for the JK injectors but install the JL injectors.

From reading on line, seems like a lot of people see between a .5-1 mpg boost but not all. I suspect it depends on driving style but don’t know that for a fact.