ZJ and WJ axles are LP

 

Quick question: When I restart warm/hot, say after shutting off for 15 minutes, it runs really choppy for a few minutes, like it's missing on more than one cylinder. It smooths out after a while and then runs great. It never does it with cold starts, and doesn't seem too when I shut down to run into a store. It threw a CEL after doing it the other day, scan tool just said "#3 misfire" or something like that. If it's a common occurrence does anyone know what might be causing it? 2000 XJ 4.0 auto

 

Vapor lock. Heat builds up in the engine bay and causes the fuel in your injectors to evaporate. You can't start up until the fuel condenses back into a liquid.

There's a recall. I'd start with getting a free heat shield installed at the dealership.

 

yes it's very common on 2000-2001 4.0's.

Heat soak is the culprit. Dealerships "fixed" the issue by wrapping the #3 fuel injector with insulation.

 

Vapor lock, common in later Cherokees. Not much you can do about it.

 

Which is half the reason for swap.

 

only hp30 u can swap into your 2000 is from a 91-99 Cherokees only. Those hp30 from YJ wranglers are leaf sprung and wouldn't work unless u want to modify the mounting points.

 

I'd say '92-99 to be safe. '8X-91.5 had CAD, except with NP242

 

alright I ll agree with this. 92-99

 

Doesn't mean you can't swap it.

 

You could swap in a beam axle from a 2WD '85, but it isn't an upgrade. My comment was based on his implication

 

Did the 1992 MJ use the CAD junk or solid shaft? I'm told YJs kept CAD all the way to the bitter end.

 

that's right. YJ had the sucky axles until 95. And the geniuses at the engineering department replaced the axle shafts with solid ones.... With LP housings. We can never win, do we.


Not sure on Mj axles though

 

MJ followed XJ, I believe. I've seen a stock '92 with an apparently-original non-CAD D30.

 

Alright, quick question for you guys as I don't want to start another thread.

I'm planning on installing an AA SYE here pretty soon, and was curious if a 97' front DS would work with my setup (see sig)?

I will be measuring and ordering a tom woods DS after the install, but I'm hoping I can use my front DS to avoid any down time as my XJ is my DD.

Thanks!