703/784 injector swap write up
Thread Starter
CF Veteran
Joined: Jan 2010
Posts: 5,482
Likes: 25
From: Virginia Beach by way of Michigan
Any mpg increase is due to running clean injectors. smoother idle and better throttle response are the benefits you will actually get from doing the swap and it's worth it IMO.
CF Veteran
Joined: Jan 2009
Posts: 1,964
Likes: 6
From: Baltimore, Maryland
Year: 1994 1993
Model: Cherokee
Engine: 4.0
. But any home mechanic with average skills and just 3-4 common tools can swap injectors in a Cherokee in under an hour easily without rushing. There are some step-by-step write-ups on it on the forum and online but some ask you to remove way more stuff than you really need to. There's nothing wrong with removing more stuff but it isn't really necessary. As no rdplz mentioned the main purpose for the swap is performance but some people get a mild mpg gain just by getting rid of clogged old injectors.
Senior Member
Joined: Sep 2007
Posts: 604
Likes: 1
From: puyallup
Year: 2001
Model: Cherokee
Engine: 4.0
just picked up 4 784's from the junkyard today... all the other cars were either different, already taken or in a fire
hope to hit another junkyard tomorrow and pick up a couple more
hope to hit another junkyard tomorrow and pick up a couple more
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
I could also only find 6x Ford XF2E-C4Bs so took those instead.Great thread... will be joining the ranks soon
CF Veteran
Joined: Apr 2011
Posts: 4,825
Likes: 2
From: Indianapolis
Year: '99 and '91
Model: Cherokee
I had found 4 at the JY too. Then never found anymore for about 5 months. Ended up buying 4 off a guy on CF. Now I need to find four more to make another set!
Junior Member
Joined: Aug 2012
Posts: 31
Likes: 0
From: Flushing, MI
Year: 1993
Model: Cherokee
Engine: 4.0
Here's my Injector Swap story,
I took a chance on an ebay offering and bought 12 703s. 6 for my daughter's 160,000 mile '98, 6 for my '93. soaked them overnight in injector cleaner and sprayed the heck out of them with carb cleaner. I didn't do the whole hook it to a battery and backflush thing...call me lazy.
Installed them in my daughter's '98 and BINGO! the thing runs like a champ. I may have had similar results with a complete cleaning of the injectors I took out of her Jeep. A failed/clogged injector on #6 started this process, everything was scary dirty including the fuel rail. But I wanted to try the 703 swap after reading so many success stories.
I also swapped 703s into my 70,000 mile '93. I had a hard time getting it started, still not sure why but after many, many tries and letting it sit for a couple hours it finally fired up. The improvement is not as dramatic (again, the '98 was really dirty) but part throttle response is improved.
Ready for the improved MPG!
I took a chance on an ebay offering and bought 12 703s. 6 for my daughter's 160,000 mile '98, 6 for my '93. soaked them overnight in injector cleaner and sprayed the heck out of them with carb cleaner. I didn't do the whole hook it to a battery and backflush thing...call me lazy.
Installed them in my daughter's '98 and BINGO! the thing runs like a champ. I may have had similar results with a complete cleaning of the injectors I took out of her Jeep. A failed/clogged injector on #6 started this process, everything was scary dirty including the fuel rail. But I wanted to try the 703 swap after reading so many success stories.
I also swapped 703s into my 70,000 mile '93. I had a hard time getting it started, still not sure why but after many, many tries and letting it sit for a couple hours it finally fired up. The improvement is not as dramatic (again, the '98 was really dirty) but part throttle response is improved.
Ready for the improved MPG!
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
784s are found in Dodge/Chrysler/Plymouth vehicles around 1998-2000 with the 2.4L engine. This includes the Neon all the way up to the Caravan.


