buysellny

Mine have a heavy pedal to ingage a downshift around 50 to 60mph.. sucking far more gas then my stock injectors. How about you? Im flooring it now to get a downshift??? Not with my stock injectors...

These injectors are working good off the line but are nothing to write home about and high speed is WAY less in my opinion.. The stock injectors would fly me to 90mph in less then 15 seconds..

My old injectors were professionally cleaned by the guy i got the truck from last year.. for whatever professionally cleaned means..

Im trying to save gas and keep the same power or use same gas and get more power.. all Im doing here now is using more gas for less high end power.. I have to sink the pedal to engage a lower gear at 50mph to 60mph.. Off the line and low gear is about the same

gully369

I may be wrong but I thought the main reason for upgrading, I've been following this thread and have read every post, was to switch from a 1 hole to a 4 hole, since 4 holes will give better atomization of the fuel for detonation. What I have gathered from all this information is that if you have a 4.0 HO you should be getting the 703's...

I have not made this swap yet but I have yet to read a post saying anything but good things about them in this thread.

wildbill1

My tail pipe was black right after I installed 784's. Since I've run a couple tanks of gas through it, it seems to be getting better. I think the ECM is learning, but it's taking a while. I'm not really noticing much change in fuel economy (approx. 16-17mpg), but the idle smoothness and throttle response seem better with the new injectors.

I plan to install a new upstream O2 this week. My XJ has 118k on it and I doubt that the former owner ever changed it. I'm hoping the new O2 might make a difference in MPG.

Reefmike

I swapped in the 703's yesterday. Took about 45 min.
Right off the bat I've noticed a smoother idle and better throttle response. Getting back on the gas between shifts feels much better. Haven't had a chance to get out on the hwy and open it up yet.

You need to make sure and flash/reset the computer after doing the swap.

wildbill1

Won't the PCM/ECU recalibrate from O2 input without resetting the computer?

Reefmike

I don't know if it will re-learn without resetting it. Several places I've read refer to resetting it after doing upgrades, etc.
Here's a little write-up from the Quadratec website - http://www.quadratec.com/jeep_knowle...article-89.htm

TrollHammer

I've been over and over the dizzying amount of info on this thread and others about injector swaps and I'm almost sure I have my answer, but I'd like someone to check me on it.

My daily driver is a '91 and is pretty much stock (wheels, gearing, computer, etc) except for the "stock" add ons I've put in as I've found them (cruse control, various dash switches, etc) and the engine.

The engine is a 98 block, heads, and intake. The previous owner says they only had to change one connector on the swap, and he had it done at a shop.

As I'm going to keep this thing going for a number of years I'd like to get the most MPG I can. It's sitting around 17-19 right now as far as I can figure.

I picked up an intake from a 99 wrangler, with injectors and wiring harness. According to the writeup here:

http://www.jeep-xj.info/HowtoIntakeManifold1.htm

It should be pretty much a drop in replacement. As they already got the 98 intake to work in it (power steering pump and whatnot), the mounts all line up as close as I can figure. The fuel rail doesn't have a return on the new one so I'll have to use the old one with a new pressure regulator for the new injectors, as that write up mentions that without upgraded injectors the upgrade will have little effect by itself (intake only). I'll also have to use my old throttle body or modify the new one as it appears there's a vacume line different between the two (I'd rather bore out the new one and use it for more performance).

I have two questions, though.

1) Will this actually give me the 1-5 mpg improvement? I have read that this only works on the OBD1 engines (91-95) and actually a drop on the obd2 engines (96-98). I'm figuring that it's a computer thing and not someting to do with the mechanicals of the engine itself, but I'm not sure.

2) Will the 99 injectors be an ideal for me as I have them, or should I keep my old ones (200k on em as close as I can figure unless they came with the engine, which is doubtful, the plugs would be different), or dig around for some neons which would probibly bring a premium around here? If I keep the 99's I'll have to change or modify the connectors (I have the old wrangler wiring harness with the 99 plugs).

rainman

If it were me I would drop in the tJ manifold and find some 703 injectors, use the old t/b And leave it at that(in fact I have done exactly that).
The newer TJ injectors are still single hole EV1 injectors, desinged to work at 49 psi, and take a different injector connector. (so what is the point?) you should also get a 49 psi fuel pressure regulator if you go down the use the tj injector path. Even that has some built in limitations.

dilljeepo

Holy crap I don't know which ones to use now. After reading wildbill1 and buysellny posts for their 99+ Jeep cherokee injector upgrades, I haven't come to any conclusions! I am in the same boat as you guys, I'm either choosing from the 784's or the Ford ones (CM4956). The ford ones are supposed to be better according to some UN-scientific articles (4 hole being replaced with a single hole but single hole is better because of "internal orifice") but reading you two guys it seems the 784's are better because the Ford ones were "worse than the stock injectors". Do either of you guys have anything different to report now? Better fuel mileage yet? Do you guys think it's 6 of one, half dozen of the other? I've been reading too long to come to NO conclusion

buysellny

Hi! I love this site.. I’m on here every day now.. I like to screw around with this Jeep.. I love it! Anyway.. Since my last post, which I said I would I did a fill up on 89 Octane. I am now sitting just slightly below the 1/2 tank mark on the fuel gauge. I have gone 134 miles. This is only the 2nd fill up on fuel. I reset the ECU as directed by people on here as well. The Jeep is totally Stock. Before I did this change of injectors to the Fords the following was done to the Jeep a couple months back: New Coil, Plugs, New A/C and Evaporator w/ Charge, New Serpentine Belt, Flush Coolant, New Thermostat, Seafoam Throttle Body with Blue Smoke Burning out of back ( Actually made the truck run great!! Seafoam was better then injectors!) Seafoam the tank, the truck ONLY gets Mobil 1 Full Synthetic High Mileage Oil as per prior owner when I bought it. He told me he had the injectors cleaned or rebuilt in 2009 for 275 bucks. I also did a bunch of other minor things like headlights, wiper motor, Front Brakes and Rear Brakes.. Brake Flush all on my own.. I am at near my mechanical limits with those jobs.. Took me hours to do drum brakes due to defective pin being inserted into the shoe as loose. etc.. Anyway, so I ran out of things to toy with, My idle jumpy and the truck would misfire in Summer and once stalled out, so TSB found and I wrapped injector 3 for Heat Soak issue.. That fixed that.. I then decide to change the injectors to those brand new Fords for 60 bucks for all six lol ( Comon!.. 60 bucks? Im saying how is that possible.. So for 60 I walked into the store in Ronkonkoma NY right down the street from me and bought them from a bunch of guys in a room with a warehouse.. Unknown local parts place that does internet business... They are selling on eBay right now.. Ronkonkoma NY Seller.. Thats Long Island.. I live 1 mile from their warehouse. Anyway, They looked brand new.. I said to the guys as I was walking out the door, " How can you sell these for 10 bucks an injector as new?" They said we buy in bulk.. They came in plastic sealed baggies.. They look brand new and not rebuilt thats for sure.. I walked out of the place wondering how could that be.. 60 bucks? for 6! Everyone else was double the price for used and rebuilt and supposedly these were the best choice according to that post..

Anyway, now here is the result so far.. I am stomping the gas to engage lower gears in the tranny at 50- 60 mph or so to pass other cars.. It feels as though IM waiting for it to misfire .. like its got less power or something.. You know what I mean? Its the only way I can describe it.. They are installed properly with no leaks.. They work GREAT off the line as I said before.. Anyway, I think my gas gauge is screwed up so I’m going to run this tank completely out to get a real calculation of mileage and function of gas gauge. Right now it looks like crap! I wonder if I will be changing the fuel filter on running this tank out at 177K!

Anyway, you have got to ask yourself one simple question: WHY ARE THESE INJECTORS ONLY 60 BUCKS OR 10 BUCKS EACH BRAND NEW... No matter how long you look, no matter where you search, you cannot find any information on specs or functioning of these injectors from any manufacturer or Ford Motorcraft on them..

I wonder how COAS and / or Rainman found the specs on the injectors: XR3E 9F593 A4B.. No one knows ANYTHING about them other then that aussie post or maybe FORD?? I can't find a single document anyplace stating anything about them..

I’m going to see what happens on this tank run out and I will keep you posted.. In the meantime who has documentation on these injectors? Also why am I the ONLY guy on here who ever posted their use. After me, people started posting their use..

Who in the hell is actually posting on this website about these injectors!! I WONDER!!! I bet a lot of vendors posing as USERS!!!

60 bucks for 6 new injectors supposedly the latest design in single hole atomized spray pattern? I beleive COAS and Rainman as they say test it out of car to see.. But I wonder WTF! I also wonder who is posting as vendors and who are real users..

buysellny

Bill tell me where is that part located on the truck and whats the best deal you found for it? I KNOW nothing was done to my truck.. everything looks SHOT lol.. Please let me know, I wanted to do o2 sensors as well.. Whats an Upstream o2?

buysellny

I’m just going to add that maybe I need to run a few tanks of gas through this thing for the ECU to learn.. I showed 10 houses yesterday for 4 hours straight stops and starts short trips all over long island at least 25 starts and stops.. This is what rainman suggests for the ECU to learn the new injectors.. So, I will stick with these for a while to see what happens.. I will run this tank of gas OUT then fill up two more times and come to a conclusion.. That’s about as good as it will get.. But each Jeep is different! My stock, rebuilt injectors Kicked ***! I was doing this change simply for the information posted on this website about 4 hole and atomized spray being better for gas mileage, performance and power. I HOPE I just need to give it more time..

IM STILL CONCERNED WHY THERE IS NO INFO ON THESE INJECTORS ANYWHERE ONLINE BUT YOU CAN BUY THEM NEW.

Here is the Part Numbers according to: http://www.ausjeepoffroad.com/forum/showthread.php?t=92236

I got: XR3E 9F593 A4B

But there is no info anywhere on ALL part numbers and cross reference of:
MOTORCRAFT #CM-4956,CM4956 XR3Z9F593AB, XR3Z-9F593-AB, XR3E9F593A4B, XR3E-9F593-A4B, YR3Z9F593AB, YR3Z-9F593-AB=all the same injector

Someone find me a spec sheet or Documents on it! Thanks

TrollHammer

Thanks for the input! Reguardless of injector I'd figured I'd get the adjustible regulator mentioned in that writeup link above, as any other type of injector was going to need more pressure. As far as the TJ injectors, I figured that pretty much everything about the engine of one was pretty much the same as an XJ, and as I had them they should work. I was just weighing out if they would be better than the old ones run at a higher pressure? They're free, I just guess I'm lazy and don't want to buy an extra set of orings and whatnot to try them to see if I like them before buying something else.

That said, if you are saying the 703s are an increase in mileage by themselves I'll have my cousin start looking for them, as they'd probibily be free for me that way (or cheaper by far than the dumb bone yards around here!)

Pa XJ

ok so i have read through most of these pages, and i went by the chart posted, went to junkyard to get the 703 injectors, but what i came up with is a 0280155976, now i knew i was looking for 703's so i pulled about 3 cars apart, both a neon and two stratus and all had the same ones, all three cars for 96 or 97, and had the 2.4 in it, so are these the correct injectors or updated ones, or do i need to go back and find the right ones

Reefmike

Here's the list I went by. Some models are 2.4's but some are 2.0's.