I have been skimming the forum for quite some time now but finally decided to make a post.
I finally pulled the trigger on the 4-hole fuel injector upgrade on my WJ with 156,000 mi
and I sure am happy I did. I ended up getting them from flamethrower (injectordyne) on ebay.
The swap went easy after lubing the o-rings up a little and cleaning out the fuel rail.
As soon as I started the engine and rev'd her up a few times I noticed a smoother idle right away. Its not perfect but my water bottle doesnt shake in the cup holder anymore.
After the first test drive I noticed a tiny bit more power going up a few hills I drive every day that are long and steep, and a little better throttle response.
I cant say for sure yet If I have gotten better gas mileage but Im keeping track of it all week to see if I can get above 16mpg.
I will put an update up in a few days.
I've bee running them for over a year and I can sure tell the difference. I haven't really gained any milage maybe 1-1.2 mpg, but I also changed the fuel filter too. I can tell the difference in the idle and that's what bugged me the most.
The difference in idle and response is amazing. I didnt think I would really see that much of a difference. Once I run this for a week or two next step is the hypertech programmer and an intake to see what I can really get out of this 4.0l on 89 octane.
This injector is also recommended by some - US $ 12 from China - Alibaba - US $ 44 from Fiveomotorsport.
Type: Injector Nozzle ; OE NO.: 4L8E-A4A ; Size: Standard ; Car Make: Ford ; Model Number: 53032145AA - see pic's
is there a benifit to this in a 4.0 if the factory ones seem to be working fine? More power?
Most people claim a small power/mpg increase. The replacement injectors have four spray ports as opposed to the one port on the stock ones. This creates a more uniform spray for allegedly better combustion. I definitely want to try it but can't get confirmation on an exact part number (either Bosch or Ford) for 2004 4.0L WJ.
Sorry I haven't put a part number up yet I cant see the number by just rotating the injector, I have to pull one and don't have time to pull the fuel rail off again right now. I know one ebay seller listed a bosch number but I don't know how accurate it is. After a few days I am more than happy with these things, Its not that noticeable as far as an all out power gain. It feels like it has more pep to it and the acceleration is much more smooth. I am keeping an eye on fuel and after 85 miles I haven't used a quarter tank up yet so if this keeps up I am one happy WJ owner!
As far as the install its pretty easy as long as you remember to put a little lube on the injector o-rings. The guy I got them from offered instructions but I have taken the fuel system apart more times than I can count when I used to wrench on these for a living. All you really need is a flat head screw driver a 10mm socket with extension a 13mm socket and some rags for the gas that comes out of the rail.