Everyone makes this sound easy and well worth the upgrade so I'm considering upgrading my son's 2000 XJ 4.0L (156k miles) stock injectors to some 784's from Programbo:

https://www.cherokeeforum.com/f11/78...ectors-110829/

and have a fuel pressure release question. I don't recall if the fuel rail has a pressure test port on it but I am assuming this is how you would release the pressure from the fuel system?

Once the pressure has been released can we then remove the fuel rail and the injectors?

Once I re-install everything, I think I read someplace that the computer needs to be reset? How do we do this?

Thanks - Mike

 

There should be a port to release the pressure. Take the battery cables off and hold them together for 20 sec. or so to de energize the memory. It may take 50 restarts to retrain the computer

 

With a bit of digging, I just found a write up on the injector swap:

https://www.cherokeeforum.com/f67/70...rite-up-66456/

This forum is great!!!

 

even after draining the pressure, you will still lose fuel out the fuel rail when you disconnect the fuel line. so use some rags along the top of the engine and one to catch any fuel that may come out of the end of the rail.

 

Here's another write up over on the Jeep Forum with pics!

http://www.jeepforum.com/forum/f11/i...-4-0l-1224714/

 

That's actually the better of the 2 write ups. Aside from the fact it has photos there are a number of steps in the first one you don't really need to do. If you want a bit more room to work you can but in most cases the average home mechanic can pull this off without removing the a throttle body or air intake hose. It's a pretty simple job actually. I've done it in 15 minutes before.

 

I just did it and it is super easy.