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So as I have said in previous threads I am a newbie mechanic so I like to take lots of pics while working on my 1992 Rodeo with the 3.1 engine so I can remember how everything goes back together.

I noticed I wasn't getting very good gas mileage lately so I was doing some trouble shooting when I noticed fuel leaking out from my pressure regulator and one of the injectors didn't seem to be working as good as the other. I ordered a rebuild kit from Rock Auto and watched a few YouTube videos to learn how to install the kit.

Here's the pics and a short description of what they show:

First thing is to pull the fuse for the fuel pump and let the engine run until it dies to relieve the pressure from the fuel lines. Put the fuse back in and then disconnect the neg. battery terminal.

You can see my TBI is pretty filthy, along with the rest of my motor. I have only had this Rodeo a couple of months and the PO didn't take very good care of it so as soon as it warms up everything will get a good scrubbing.

Next remove the air cleaner by disconnecting the vacuum hoses and electricals from it and store it out of the way.


Remove the electrical clips to the injectors by squeezing on the two tabs (red) and pulling straight up.


Disconnect the fuel supply and return lines (green arrows), throttle cable (blue), throttle cable bracket (red), electricals (orange) and a half dozen vacuum hoses (not marked).
Then remove the 3 bolts (yellow) from the throttle body and lift the body out. Then find a comfortable place to work on it.


Now remove the rubber parts (blue) from around the injector terminals. Then remove the 8 bolts (yellow) and tap along the sides of the meter cover and regulator assembly with a plastic screwdriver to break it loose. The assembly is pretty fragile so be careful when removing it. I wouldn't try prying on it with a screwdriver, ya might bust it.


To remove the injectors place a wrench or round punch between the edges of the casting around the injectors and use a flat tipped screwdriver to lift the injectors up and out of the fuel meter body.


Each injector has two O-rings (yellow) - a big one on top and a small one on the bottom - and two filters screens (blue) - one on the bottom and a tiny one near the top on the side. Replace all these with new ones from the kit. When putting the injectors back in it helps to soak the O-rings with tranny oil so the injectors slide in easier.


Next remove the fuels supply and return fittings. Each fitting has a plastic washer on the end, replace these with the new ones.


Now remove the fuel meter body by removing the 3 screws (yellow)


Throttle body assembly on top, fuel meter cover & pressure regulator assembly on the bottom left, and fuel meter body on bottom right.
Give them a good cleaning now that they are apart. Don't forget to squirt some cleaner in the vacuum line ports. Two of mine were almost completely plugged up.


To rebuild the pressure regulator remove the 4 bolts (yellow) from the regulator cover. There is a large spring between the diaphragm and the cover so squeeze the cover against the assembly as you remove the bolts so everything doesn't go flying apart.


Remove the old rubber diaphragm and replace it with the new one. Then assemble in reverse order.


Install all the gaskets and assemble everything in the opposite order that ya took it apart.

One thing to watch out for is the injectors can only go in one way. There is a small round tab on the bottom of the injector (blue) ...


... that fits into the notch in the bottom of the fuel meter body (blue) and as I said above it helps to soak the O=rings in some tranny oil so they will slide in place easier.


All in all this was a pretty easy job, even with my limited mechanical experience. The whole thing took just a couple of hours and now my Rodeo is running like a champ again.

Hope this helps someone out.

Good luck,
Shane
 

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Very nice job and write up! Thank you!
 

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An excellent and Most Informative Writeup! :thumbright:
 

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Great write up. Thanks for the details. Dennis
 

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Yea its not a bad job and after a few hundred thousand miles its worth the time and money for the results you get. The TBI system is simple and low tech compared to the systems out today but it asks for hardly anything of its owner. I have never done anything to the fuel system on my TBI vehicles other than change the filter. I have never had to replace injectors, gaskets or the regulator. I have only done it because I have been modifying things or otherwise toying around.

For anyone taking on this job in the future. It is not necessary to bleed off the fuel pressure. The system will bleed off its minimal amount of pressure once the pump stops running. When you loosen the ful lines make sure you have paper towel or rags below to absorb the drippings. You don't want fuel puddling in the intake manifold. When you go to un screw the regulator be sure you have a hold on it. If you loosen the screws and the thing pops open you may find yourself crawling along the garage floor looking for lost parts.
 
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