Year of the Jeep?

 

1990 Cherokee with a 94 HO engine and 99 manifold. I upgraded to the Pressure Regulater fuel rail when I built the Jeep.

 

Alright guys. I have a '94 XJ with the 99+ intake and TB bored to 63mm. At first I was running the 99 injectors, and was having problems. After doing all the research, I found out about all the different pressures the XJ's run at (9?+ ran at 49psi.) So, I went and got the Yellow ford EV6 style injectors. I installed them and did not see any difference. Then after reading this entire post, (thanks coas) I found the different FPR's. I went on E-bay and got one of the FPR's list in this post, and just installed it tonight. I only did a quick run down the street, but I did notice a difference this time. Seem like a quicker throttle response, smoother idle, and the exhaust gas smells, and feel like she's running like she should be.

Even though I think I was drooling after read this entire post, it did help me out. Many thank to all the threw their 2 cents in.

Thanks,
J

 

glad we could all confuse... help.... confuse.... help ya! lol

 

http://www.polog40.co.uk/article_injector_table.php

Good site that shows what the different Injectors flow By Bosch Part#...Remeber 3 Bar is roughly 42PSI...so you Renix-95 guys running 39psi base. Results will very but be lower....also for the guys 96+ who run at 49PSI constant your flow numbers will be higher......

 

The table is not accurate.
Look at numbers for the 0280155702 and 703, it should be the same.

A perfect example of an engine that was running lean, the high pressure FPR not only added more fuel but also increased atomization. Wait for the emission check results.



Always make sure your injectors are clean before installing, some were complaining about lack of improvement or worse performance. It turn out they didn't clean the injectors properly.

Use this method, it took me some thinking coming up with an effective yet easy and inexpensive:

http://www.youtube.com/watch?v=http:...?v=VFJlTfHyrUk

There are many lists on the net specifying injectors flow, one have to bear in mind that flow vary by many variables, the fuel octane, temperature, fresh or old, test machine accuracy, number of injectors (the average of X injectors), ambient temperature (measuring tube expansion), altitude, barometric Pressure,relative humidity...
Some lists, like Stan weiss list are a collection of data that were performed on different machine, different fuel...

Injector will flow X in certain conditions and can flow X+10% in different conditions.
If we use the Neon injectors which flow 248cc of Heptane, add 10% you'll get ~273 cc.

This mean, that injector flow in Colorado will be different in Australia , different fuel, different
temp, barometric Pressure, humidity... For this, car manufacturers always installing an injector with sufficient margin or a different injector altogether.

A good comparison must be done on the same test bench, same ambiance conditions, same fuel specific gravity. Since the above is not available for most of us the only other way (beside trial and error) is using manufacturer data, i.e Bosch, Siemens and others.

 

Review / Update

 

Great info! Thanks for the heads up. Now I know what to look for in the junkyard, other than a neon.

 

as far as cleaning injectors goes... would i be able to throw them into a ultrasonic cleaner and just do that? or will that be harmful to the injectors?

 

I don't see why that would be an issue. If you wanted to play it safe hang them so just the injector tips are in the cleaner

 

all right! thanks... that will be tomorrows project.

 

Yupp I'd say to play it safe keep the electrical connector part out of the cleaner. Ultrasonic cleaners typically operate at about 150F but I know the Intake manifold gets at least that warm from sitting right over the exhaust.

 

so, should i just put them in vertically and have just the tip in, or put them horizontally with the electrical connector up and out of the solution? Thanks!

 

can anyone tell me why injectors with the part #0280155700 does not fit in my 99 cherokee? There have been a lot of posts within this thread that say they will fit but I bought a set of 8 and the electrical connections on my cherokee and the new injectors are different.

 

what were they for? you got the proper connectors for your 99 too right?