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Upgraded 4 hole Bosch injectors reduced my start time on my renix by like 90%....

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Old 01-23-2015, 07:17 PM
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Default Upgraded 4 hole Bosch injectors reduced my start time on my renix by like 90%....

So I have done literally everything possible to reduce the start/cranking time on my Renix already. Not that I was specifically targeting it, just over time I've done it all, except for injectors.

The XJ seriously starts faster than my 2014 F150 work truck now...

Also increased my throttle response greatly, as was expected.

So ya.

Last edited by Stabsthedrama; 01-24-2015 at 09:58 AM.
Old 01-23-2015, 09:41 PM
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I recently read about this and am interested in doing it. Other than startup, what's your impression about how it runs? What's the PN (or source vehicle) for the injectors, where did you get them, and how much $?
Thanks.
Old 01-23-2015, 10:19 PM
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Originally Posted by '90Cherokee
I recently read about this and am interested in doing it. Other than startup, what's your impression about how it runs? What's the PN (or source vehicle) for the injectors, where did you get them, and how much $? Thanks.
tons of guys sell them on this forum for $80
Old 01-23-2015, 10:42 PM
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Did nothing for my crank time, still takes what seems like 5-6 revolutions to start.
Old 01-24-2015, 01:16 AM
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Here on the forums or on ebay, whatever is available at the time.

Don't pay more than $100 for a set.

Re-furbed Bosch Type III 4 hole or refurbed Volvo 746 injectors is what you want. Get them from a reputable place with new orings/cleaning/etc, it's worth the money.

Do the o-rings on the fuel rail ("quick disconnects") as well, they are found in the Dorman Help! section of any auto store - part kit #90100, GM/Chrysler fuel rated o-rings. Also do the O-ring on the regulator, it's the same size as on the injectors, which comes in the #90100 variety pack.

DO NOT BREAK THE STOCK PLASTIC CLIPS FOR THE FUEL QUICK DISCONNECTS, JUST LEAVE THEM ON THE MALE SIDE OF THE DISCONNECT, YOU WILL NOT FIND THEM IN STOCK ANYWHERE, and if you order them, they are $25+ at a stealership or Napa, or you can get them at Morris but will have to wait for delivery, part #83502745.

THE DORMAN 5/16 CLIPS ARE NOT THE SAME! Wish I had known this before snapping one of the originals off... They do not butt up against the o-rings, and ANY SHORTCUTS IN THIS JOB CAN AND WILL CAUSE A LEAK AND THEN ENGINE FIRE.

It might sound difficult/scary, but it's an easy job. An angled pick and the flat side of a skewer (wooden stick) is all I needed to take out/replace the o-rings and spacers at the quick disconnects (after dipping them in engine oil).

Any time you disconnect the fuel quick disconnects you replace the o-rings, BUT....

KEEP THE SPACER IN BETWEEN THE ORINGS AND KEEP THE PLASTIC CLIPS, JUST REPLACE THE O-RINGS WITH THE DORMAN FUEL RATED ONES.


With that in mind, just get a set of injectors, a set of the o-rings, and be careful not to break and vacuum tubes in the process (disconnect the map sensor tube ahead of time just to get it out of the way, I had to make a new one), and unscrew the 3 torx bits holding the bracket for your throttle cable to be able to get at the one fuel rail bolt. It's a simple job, tons of DIY writeups on the internet. 2 hour job if you really wanted to.

If you break an EV1 (injector) connector, which you probably will, I got lucky and only broke one - Just ziptie the plug around the injector when done, it ain't going anywhere if you do that, mine is snug as a bug.

Also the new injectors do NOT need to the clip slots on them, and you do not need to reuse the fuel injector clips, those are only for ease of assembly/testing at the factory, the injectors aren't going anywhere once seated and the fuel rail is bolted. 2 of mine didn't even have the clips on them and probably didn't for the past 20 years and never leaked.

I wrote all of this because I wish there was more specific info on these parts of the process on the internet, but only a few posts mention these things in detail.

Last edited by Stabsthedrama; 01-24-2015 at 09:55 AM.
Old 01-24-2015, 09:28 AM
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Thanks for the extra details.
Old 01-24-2015, 09:52 AM
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Edited/added some more stuff. Have fun.
Old 01-26-2015, 08:23 AM
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Originally Posted by '90Cherokee
I recently read about this and am interested in doing it. Other than startup, what's your impression about how it runs? What's the PN (or source vehicle) for the injectors, where did you get them, and how much $?
Thanks.
Volvo "746" injectors for the Renix like yours.
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