How to...

[DIGITRUCK]

Hey,

88 XJ Cherokee Laredo 4.0 Auto. I'll prolly change my injectors soon. I'd like to know how/what steps are involved in order to:

1. How to release fuel pressure before working on it?

2. How to remove fuel rail and fuel regulator?

3. How to remove the O-Rings and What sizes/quantity do I need?

4. Do I need any specialized tools for the quick disconnect on the fuel regulator etc and/or performing this job?

5. Did I miss anything (Tips/Tricks/Advice)?


Thx, Phil

[90XJINPA]

Originally Posted by DIGITRUCK

Hey,

88 XJ Cherokee Laredo 4.0 Auto. I'll prolly change my injectors soon. I'd like to know how/what steps are involved in order to:

1. How to release fuel pressure before working on it?

2. How to remove fuel rail and fuel regulator?

3. How to remove the O-Rings and What sizes/quantity do I need?

4. Do I need any specialized tools for the quick disconnect on the fuel regulator etc and/or performing this job?

5. Did I miss anything (Tips/Tricks/Advice)?


Thx, Phil

Go here---> http://www.southeasternxj.com/tech/tech_injectors.htm

I just did this and it made a world of difference. I got the injectors from a Ford 92-984.6 V-8, be sure to get all 8 so you have an extra or 2.

The info on how to do it is right on.

If when you are done, it doesnt seem to be running right, check each injector to be sure it is working. To do this, while it is running pull the electrical connector off of each injector one at a time. If the idle drops when you do this the injector is fine. The last one on mine, closest to the firewall was bad on mine.

Good luck.

[DIGITRUCK]

Originally Posted by 90XJINPA

Go here---> http://www.southeasternxj.com/tech/tech_injectors.htm

I just did this and it made a world of difference. I got the injectors from a Ford 92-984.6 V-8, be sure to get all 8 so you have an extra or 2.

The info on how to do it is right on.

If when you are done, it doesnt seem to be running right, check each injector to be sure it is working. To do this, while it is running pull the electrical connector off of each injector one at a time. If the idle drops when you do this the injector is fine. The last one on mine, closest to the firewall was bad on mine.

Good luck.

Hey 90XJINPA,


Wow, that looks to be some very thorough instructions! A few more q's:

1. Does the O-Ring Kit come with O-Rings for the Fuel Regulator too?

2. When you mention pulling off each electrical connector one at a time to see if the idle drops...do you place it back on then move to another and remove that or leave it off eventually having only one injector firing or not?

3. Do the Injectors screw in or are they press fitted? I know stupid q but I've never done this before. lol


Thx, Phil

[Saudade]

I did this on my '88 with injectors I got from eBay.

As far as I know, the kit is for the injectors (12 o-rings). Since you don't need to remove the regulator from the rail, you don't have to do this, BUT, as long as you have it all apart, might as well.

You should replace the connector on the injector after testing it. So remove one, see if the idle drops, then reconnect, idle should climb and smooth out. Then try the next one.

The injectors are held in only by the "press fit" of the seal. They should pull right out but will likely take a bit of wiggling. Two of my injectors were really stuck in the manifold from a lot of carbon buildup. I used some carb cleaner and a bottle brush to clean the bores out before installing the new ones.

Getting everything to align was "fun". I put all my injectors into the rail first and secured with the clips. I then put the rail with injectors back into the manifold. Work slowly and carefully to get each one started into the bore, then you'll just need to keep pushing until they all seat fully. You'll know when because the mounting flanges on the rail finally rest on the manifold.

I thought I could get away without the coupler kits on the fuel delivery and return lines. I was wrong and sprung a huge leak on the delivery line because I damaged one of the little o-rings when I removed them. Fortunately, I have a collection of o-rings and found one to fit.

Good luck!

[90XJINPA]

I ditto what Saudade wrote.

I did the injectors in the engine first, and then in the rail. I had a friend to help. An extra set of hands is a great asset.

The o-ring kit does not come with one for the pressure reg., but do take the time to replace it. It is the same size as the injector o-ring.

It really is an easy job that pays big dividends.+

Have fun with it.
Later