http://coloradok5.com/forums/showthread.php?t=301416This isnt mine its PMA4X4 the link posted above will take you to his post on coloradok5. he also posted on a couple different forms. now as some of you know i have my 91 v3500 he put over $600 into his mods which to me is a litle high for a tbi. but i want a little more power before i swap my tbi out for my cummins. so im going to be adding what i have done to mine or will be doing at the end of the post. if you got the money have fun but if you want something for cheap like me ill be doing my work myself.
If you just want to
rebuild your tbi Chris also has a good write up on that.
Spring for GM 17113186 vAFPR (Vac. Adj. Fuel Press. Regulator) this is the spring Chris used in his write up
This write-up is for pretty much all the TBI upgrades you can do. This is done step by step with a ton of pictures so as long as you have basic mechanics skills and a manual at the ready you should be able to do this upgrade. You should also be able to use this write-up as a guide for basic TBI overhauls or fuel injector replacing. I tried to be as thorough as possible. If I missed something please let me know.
Parts:
Bored out Throttle body #62-350b
Rebuilt and matched fuel injectors #62-FI
Injector Pod
Fuel pressure gauge adapter #62-FP
Fuel pressure gauge 62-PG
Adjustable fuel pressure regulator - 62-FR
Injector pod spacer
Powerplate (TBI Spacer) #PP-100
Hypertech Powercharger (Salad Bowl) #4001
Amsoil EA performance dry air filter #EAAR31
Tools:
13mm socket
Standard screwdriver
T-15 Torx
T-20 Torx
T-25 Torx
1/4” allen wrench
Other miscellaneous tools needed as well
NOTE: The Torx bits should be in a screwdriver
setup only. IF NEED BE you can use a ratchet to remove screws but only
use the screwdriver upon reassembly.
Parts to be installed
So here we go! We will assume you are starting with the air cleaner off and the battery disconnected.
You will need to disconnect these items from the TB in order to remove it from the intake manifold.
Disconnect the two electrical connectors to the Throttle Position Sensor and the Idle Air Controller. NOTE: The clips that hold these on are probably brittle so be careful not to over bend them otherwise they may break like my IAC one did.
disconnect the three vacuum lines on the front of the TB
Using a 17mm and a 19mm wrench (preferably line wrenches) to remove the main and return fuel lines from the rear of the TB. Remove the single vacuum line as well.
Using the flat blade screwdriver pop the two clips off to remove the cruise control and the throttle cables. While hold firm the throttle linkage grab the TV cable connector and pull it forward by hand and it should pop off.
NOTE: DO NOT PRY IT OFF YOU COULD BREAK THE CABLE... BAD!
To remove the electrical connectors from the top of the fuel injectors pinch by hand the two points in the middle and carefully wiggle while pulling it up.
Using the flat blade screwdriver pop out (working forward) the weather plug that contains the injector wires.
Always make sure to cover your intake ports even for just a minute!
Use the 13mm socket and remove the 3 bolts on top of the TB. once out you can then remove the TB from the engine.
Use the T-25 Torx on the two screws to remove the TPS sensor from the TB. Use a 32mm socket to remove the IAC from the throttle body.
The TPS is under a small amount of sprung wound tension, nothing to worry about. Once both the screws are out it will turn to a natural position like you see in the pic below. REMEMBER: when reinstalling set it back to this position then turn to line screw holes up.
Using the same T-20 Torx bit to remove the eight screws that hold the injector pod top.
If it doesn't just come loos lightly tap the top housing with a rubber mallet or plastic hammer. Mine just took a small single tap.
Remove the fuel injectors by using a flat blade screwdriver under the lip in the center of the injector. Use another screwdriver to place on the edge of the housing and use that as a pivot point. the injectors will come out easily just a bit slow.
Using a T-25 Torx remove the three screws that hold the injector pod on the main TB housing.
Unscrew the fuel line flanges using a 19mm wrench. Hold the TB firmly. When you do remove them make sure the little clear plastic washers came out with them. If you accidentally double stack them they may leak.
Continued on next post...