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Bosch 4 hole Injectors Installed Today.

9K views 44 replies 9 participants last post by  rkymtn05 
#1 ·
So I pulled the trigger and bought some Bosch 4 Hole injectors on Ebay for my 2000 Wrangler with 180K on the clock. Installed them today and to anyone thinking about doing it's "EASY". Plenty of threads on how to do the install so I'm not going to say anything more about it other than they often don't mention eye protection. The potential for gas in the eye is pretty high!

My primary reason for doing this after reading many posts..

Old ones likely needed to be serviced @180K and the new set cost less unless I serviced them myself. I just felt my time was worth more than the new flow matched set for $119.00 delivered.

Working great and other than tightening my exhaust down pipe at the manifold it's the only thing I changed. So that said stay tuned for some updates on the key issue of fuel economy. Some people claim 1-4 mpg gains and I was getting 10-12mpg before the change. The way my jeep is loaded up hasn't changed in a couple of years but my fuel economy has dropped by 1-3mpg. I'm aware that an exhaust leak upstream of the O2 sensor can effect fuel economy but from what I can tell mine wasn't leaking.

I'll post updates!
 
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#2 ·
Good post...I just hit 153k on the clock and thinking about upgrading too. My mechanic quoted me a lot more so I'd be interested in where you got them. Also, I haven't read all the other posts you might have read, so what did you hear about their reliability vs. OEM?

Thanks man,
 
#3 ·
#5 ·
Also the injector "clips" on my factory injectors securing them to the fuel rail where not needed on the upgraded injectors. The sleeve on my injector rail was deeper and all they do is keep all the injectors in place when you pull the fuel rail. Well not true they also keep the connector oriented up but that doesn't seem to be an issue since they don't rotate freely.
 
#6 ·
Update 1

Reset my ECM following popular the drain the capacitor method.

After a few miles of driving I'm noticing my gas needle has slowed down on its way to empty. Need to run a few tanks for a real idea of how much improvement we're looking at.

Idles a bit smoother.

Takes a bit less foot off the line and to maintain speed on the freeway. Drove in multiple directions so it wasn't a tail wind thing. Also flat with no hills I live in the Houston area.

I've got a whole bunch of crap on my roof (Thule Roof Box and 14' Kayak) so less throttle to maintain speed is really easy for me to perceive but its not a huge change.
 
#7 ·
I hear throttle response, better idle because of a more efficient fuel atomization, and easier to maintain speed are the most common improvements. I will be doing the same when I get back to my Jeep that is sitting at my dads house in Katy. You do any wheelin out there?
 
#11 ·
BOSCH 1F2E-B4A according to the Ebay listing. Plug and Play with no issues so far.

I read a ton of posts on the subject and my head was hurting afterwards! Anyway I went the easy route and spent some money but you could do this for next to nothing if you feel like hitting the pick a part near you.
 
#12 ·
I've thought about these but my primary concern is valve (and valve seat by extension) cooling and carbon buildup. The stock injector is designed to spray directly on the backside of the valve head and at the valve stem which provides a cooling effect and also helps reduce the buildup of deposits if using quality fuel. The 4-hole injectors probably will not spray directly at the valve head and stem and some of the benefits of single hole/conical spray injectors will be lost...
 
#14 ·
Update

After some careful observation using Dash Command which offers real time fuel flow monitoring I can confirm that there is no increase in fuel economy by making this switch. I backed this up with my normal old fashion fill up calculations. Exactly the same as properly functioning stock injectors! So all the guys debating fuel economy gains where way off in my experience and the claims of 1-4mpg gains are only possible when replacing faulty or dirty stock injectors.

Here's what you gain if anything.

Smoother Idle
Less peddle at cruise but that does not equal less fuel!

I hope this helps others with their decision to go this route. :cheers2:
 
#16 ·
Retainer clip not needed? Confirming.
 
#19 ·
Easy to check. Unplug each injector while running. If it gets worse, that injector is fine. If it stays the same. That injector is probably bad.

I've had them in for a while now without the clips...
Thanks
 
#23 ·
Mcon, from the looks of it, you installed injectors that were originally for ford applications. Probably not the best option for your 2000tj. The neon green injectors from the dodge caravan would probably suit you better and you might see the increase in mpg that others are getting.

http://www.jeepforum.com/forum/f9/gas-mileage-1393693/index2.html

There's also some good info and links in this thread.
 
#24 ·
That depends on his application. Actually, the neon flow less than a stock HO 4.0. You are aware right? Yes, I am aware the factory is a single hole and Bosch style is a 4-hole. But, it still flows less cc. While 99% of the people will never notice. But, the engine knows under WOT. ;) If your motor is stock, you're probably fine. If not, I would run the numbers. Ford has 19# and 24#. Stock HO 4.0 is 22.2 iirc.

This might help. Its better to use part #'s than "Ford" or "Dodge" as they vary.
http://injector-rehab.com/shop/Flow_Rates.html
 
#25 ·
those precision injectors for TJ are supposed to be the shizzy but I have yet to see anyone confirm MPG gains...I just don't think there's enough there to get with a TJ.
 
#26 ·
Tried to find the "specs" and nothing. Anyone? Curious what the cc/min or lb/hr is?
 
#29 ·
Found this info
0-280-158-023
lbs/hr cc /min grams /min PSI BARS lbs/hr cc /min 80% 95%
23.23 244.1 175.6 43.5 3.0 23.23 244.1 35.7 42.4 EV6
 
#33 ·
703 flow more. Wanting a pinch more than a 703 :D
 
#32 ·
#38 ·
Newbie's reading, please triple check your cc/min or lb/hr of your stock injector before picking a pretty color. In the end, its your motor that runs lean on WOT.
 
#39 ·
I've done plenty of research on this topic and have selected a bosch injector for my tj that is almost exactly the same flow rate as the stock siemens injector. They're not pretty but, they work flawlessly. Thanks again for you misinformed comments.
 
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