Larry’s
Electric 1-618-282-2852
GM LT1 fuel Injection Harness installation instructions
Thank you for your purchase from Larry’s
Electric. To help aid in a successful
installation, I have included these instructions. Please take the time to familiarize your self
with all the components and instructions before installing. If these instructions are not followed very
carefully it may result in severe damage or harm to your self and the vehicle. In addition to these instructions you must
have at least a general idea of how fuel injection works and be familiar with
all of its components.
Things that you need
to start.
- GM LT1 series engine and transmission, with all the correct sensors.
- GM PCM
for the correct year engine/transmission you are working with.
- Your
PCM reprogrammed or “Flashed” with at least the correct tire size, gear
ratio, emissions removed and vats removed.
Other changes are up to you.
- 2 Heated
O2 sensors (oxygen sensor) mounted in the exhaust with in 18 inches of the
exhaust port
- Electric fuel pump capable of delivering 60 PSI under all driving conditions and a fuel filter designed for that amount of pressure.
- 3/8 or larger fuel supply line from the tank (Fuel injection line 90psi min only), and a 5/16 or larger return line to the tank. The return line must end at least ˝ in from the bottom of the fuel tank to prevent vapor and static electricity build up.
- Injectors
for your size engine. If you don’t
have them already
- Retain
the Distributor harness that attaches to the distributor.
In addition to standard mechanics tools you need a 12 volt test light or meter and a digital non-loading meter.
INSTALLATION:
!!!IMPORTANT!!!
Do not force any connector into place. Take your time.
To begin, decide on a mounting place for your pcm. Working from inside the vehicle, start feeding the harness through the fire wall into the engine compartment.
Route both banks of the injector wires along the correct side of the intake manifold (the injectors are marked 1,3,5,7,2,4,6,8
Connect the plugs labeled coil plug and coil driver to your coil, being sure to connect the ground wire.
Connect the coolant temp sensor plug on the front of the engine on the water pump.(yellow and black wires, black connector).
Connect the black/white wire to a clean solid bolt on the manifold (Ground).
Connect the throttle position sensor (black, blue, and grey wires) to the throttle position sensor on the side of the throttle body. Connect the idle air motor (green/white, green/black, blue/white, blue/black wires) to the bottom of the throttle body near throttle position sensor.
Install the Oxygen sensors and connect the o2 sensor labeled wires to the correct side (purple, tan, black/white, pink wires (right side) and purple/white, tan/white, black/white, pink wires (left side)
Connect the MAP sensor located on the front passenger side of the intake (green connector, green, black and grey wires).
Connect the Distributor plug to the Distributor pig tail.
Connect the Intake air temp sensor and the mass air sensor wires (if equipped with mass air)
Connect the transmission wires to there correct location and the speed sensor located in the tail housing of the tranny
Connect the large gang-plugs to the ECM, making sure you do not force them into place and that they are correctly positioned.
The coil pig tail included for 94/95 models has a grey connector with a pink and a white wire on it. The white wire goes to a tach if you have one, and the pink is an ignition hot, power when the key is in the on position and when it is in the crank position.
96 LT1 is the same color code its just a different connector kinda orange in color.
Connect the 14 gauge pink wire to an ignition switched on (hot in start and run).
Connect the 14 gauge orange wire to a battery hot source.
Connect 14 gauge grey wire (fuel pump inscribed on it) to the fuel pump at the + terminal of the pump.
Connect “Check Engine Light” (brown wire) to negative terminal of light fixture and a 12 volt Key on power source to the positive side of light. Use Low Wattage (1/4 or less) bulb.
Connect the loose light blue, at the PCM end of the harness, to a normally closed brake switch (in other words a switch that has key on 12 volts on it all the time except when the brake pedal is pressed.)
Connect the green/white wire to your speedometer (optional check with your speedo manufacturer.)
Mount the ALDL connector out of sight, but easily accessible location for scanner connection later. (12 way black connector with an tan, black/white, and white wires)
Bleed the fuel lines by cycling the ignition on, wait for the pump to run and shut off, then turn the key off, and repeat several times.
***NOTE***
If your injectors have set along time the gas in them will gum them up and they will not work. To make sure that they are in working order before plugging in the injectors take two pieces of scrap wire and put 12 volts to one side of the injector terminal and ground to the other. The injector should make a click sound. If not remove them and have them cleaned or replace them.
Start and run engine.
If you have any questions/problems or require technical
assistance, please call Larry’s Electric @ 618-282-2852 Monday – Friday
If for any reason that
you are not satisfied with this product with in 10 days of purchase please call
us and we will refund or exchange it, as long as the product is not altered in
any way shape or form and is returned it its original box with all pieces.
Shipping is a non refundable service, we are not responsible for shipping cost
or transit times.
This product is not intended for sale or
use on any emissions controlled vehicle which will ever be operated on a public
thoroughfare. For off road use only
™ Larry’s Electric, and Larryselectricsite.com
©2007-2008
REVISION 2
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