Step By Step Real World Build Up!!!! STOP--READ FAQ FIRST

[Bill usn-1]

STOP

READ THE FAQ AT THE TOP OF THE FORUM BEFORE ATTEMPTING THIS. PRINT ALL WIRING DIAGRAMS!!

OK, I am going to try and do a step by step real world purchase and install of a GM TBI system. If I don't have a vehicle to put it in when done then I will just piggy back it on my scout!!!
Note what I bought and for How much!! It even comes with the nice caprice air filter!
Well this thread may take a while to finish but will be a running work in progress.
Hopefully with everything else that is here already, anyone will feel confident enough to take the plunge!!!


For the vehicle:

1975 Scout II XLC
Every part rebuilt.
Motor: 345- .040 over pistons. Block decked .070

Heads ported on the exhaust side. Gasket matched on the intake. Oil returns chamfered. Umbrella seals. Erson BBC valve springs.

Cam: Isky 256/264 split duration.

Manifolds:
Exhaust-Stock gasket matched.
Intake- stock 2 barrel, radiused inlet.

Tranny: 727

TC: JP Dana 300

Gears: 3.73

Tires: 33X12.50

Weight: 4950lbs empty (no tools, parts, no sliding drawer tool box)

91 Caprice 350 TBI SBC Throttle Body Injection Setup Item number: 8033214740

Winning bid: US $149.57

Ended: Feb-01-06 11:46:07 PST
Start time: Jan-25-06 11:46:07 PST
History: 3 bids (US $100.00 starting bid)
Winning bidder: usn-1 ( 140)

Final with shipping:
Subtotal: US $149.57
Shipping and handling via Standard Flat Rate Shipping Service:
US $38.00
Total: US $187.57



Description
This is a 91 Caprice police car 350 TBI setup. It ran fine - has hi mileage.. Includes: intake & throttle body, fuel lines, distributor, coil, ignition wires, air cleaner, ecm, charcoal can, fuel lines & some misc. hoses + brackets, mounting bolts & wiring harness from auto trans. It will need a dist cap & temp sensor on intake-they broke pulling it out. . It's dirty- needs cleaning.



Parts shipped on the 3rd and arrived on the 9th. Not bad to Sicily!!!
Here's what I got in the box. Notice I did not get the manifold. I ask the seller to remove the parts from the manifold to reduce the weight for shipping and allow him to sell it seperate in exchange for a discount on shipping.....Well it weighed less anyway!!

First thing to do is lay it all out and inventory what you got.
Use the pictures here to identify each part. Make sure you print these out and take them to the garage with you!
Clicky button
If you look close you will see that for a basic system I am missing 2 parts.
1. The CTS.
2. The O2 sensor.
I will have to come up with these on my own.



Connect all the parts onto the wiring harness. Most connectors are idiot proof and can only go 1 place..but there are exceptions so if your not sure, no problem, we will get to it soon!




This is the ECM I got with the system.
It is service number 16136965 with a Broadcast code (BCC) of AXFF.
When researching ECM's use this link for a good cross ref.
Clicky button






So what do we do first?

Well we need to get rid of all that old covering and tape so we can trace the wires.
A simple razor blade works fine, just don't cut into the wires!

15 min later...




and this is what I removed so far.

[Bill usn-1]

Now what do we want to do about this big thing????
Well there are a couple of options.
1. Leave it as is. If you pulled the system yourself then you could have saved the retaining clip. Then just cut a big hole in the firewall and stick it in.

2. Cut it out. You will eventually tailor the harness down to fit your IH anyway so just cut the whole harness in half and remove the plug out of it!!

3. Remove the plug from the wires....
There are a couple ways to do this.
a. use heat(hot water/heat gun) to soften the outer case of the plug. Then pry the case off the outside. There are a couple little locks sticking thru one side that will need to be squeezed with some needle nose. Then you can use the needle nose to start pulling the goo off of the wires. tedious work.

b. remove the outside case then use your heat gun to melt the goo off the wires. Hold it over a box or lined trashcan to catch all the drippings!!









So now we need to determine which wires stay and which wires go!!!

First print off the wiring list from here. Clicky button
And print off the pin out diagrams to help you trace the wires to each part.
7747 pin outs



There is also a very nice 1 page color pdf file in this [http://www.binderplanet.com/forums/s...diagram]thread![/URL]

Wiring Basics:
1. Most manufactures follow a basic wire color system. There will always be exceptions to the rule and a color may be used twice. There are also small difference from model/yr.
But some colors to note are....
pink/blk-this is 12v that is from a switched source.
red- 12v straight from the battery
org- 12v after it goes thru a fuse or protection device.
blk/wht- ground

2. Tie points shown on the diagrams will not be the physical location of the actual connection. A tie point can be any where along the same piece of wire and it will perform exactly the same!


Lets start from the top....
First connector will be the small one that has an A side and a B side.
Note the "A" and the numbers from 1-12 from right to left!



And here is the larger C and D connector.




Make sure you comb the wires out straight coming out of the connector so there are no mistaking which wire you are looking at.

NOTE: You will not be using every wire that is in the plug.
Because we are dealing with so many systems, make sure you use the wire listing and diagrams for your system. Some wire colors used will be different between different years. Just make sure that the designated pin goes to the listed location!

Now starting with A1 we see it is Green with a white stripe and should go to the fuel pump relay. Follow the wire all the way to the end.



Use your pen and masking tape and make a wire label!!! You may also want to put the name of the part it is hooked to. If the wire goes into a tie point with other wires I put a label there and at the end where it's going.

Did you notice this system came with 2 bosch style relays instead of the older fuel pump relay!! Guess I won't need to buy a seperate power relay!!!



Continue this thru the list.




2 Hours in the garage!
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[Bill usn-1]

OK you should have gotten thru all the wires that are needed and have them all labeled.

Now what about the ones that aren't needed?

Well I cut the wire 4-6" from the ECM and leave it there....just in case.

You will need to decide which of the "optional" sensors you want to retain.

Items like the EGR and purge canister wires will have a control wire from the ECM and a ground(blk/wht) or 12v wire. (pink/blk)
So after you cut and remove the wire attached to the ECM you will have to go back to each unused connector and cut the other wire. These I usually cut near the unused plug so I can use the remaining wire if needed!!
I'll show you a couple examples as we go along......

(There may not be a wire in each terminal listed)
Cut:
A2, A3, A4 cut if not using EGR, A7, B4, B6, B7 cut if not using the knock sensor, B9, B11, B12.

C1, C2, C7, C8, D3, D8-D13.

Here is the tie point for B2(fuel pump) Note the small wire going to the ECM connector is tied to the larger wire coming from the relay. It also splits to a 3rd wire that actually goes to the fuel pump to turn it on.






These are the wires I run to the ALDL.
There is the serial data-A8, the Diag term-A9, Gnd-blk/wht, and 12v sw-pnk/blk.



12V tie point.


Misc signals


The main system grounds


The 12V switched left over wires. These come in handy later!!!


Here is the 2 relay and the main power input fuse. Note the red lead going to the fuse holder. Then coming out it is org. This will be used to power the system.
The relay on the right was used to power the AC system. Since I will be using the AC signal wire(B8) to up my RPM for the OBW and OBA, I will use this relay for my main power relay!!!

The relay on the left is the fuel pump relay and is controlled by the ECM.

[Bill usn-1]

The rest of the harness









And here's what I removed.



Including the oil pressure switch connector.


Don't throw these away!!!






2 more hours in the garage....4 more hours on the computer...........
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[Bill usn-1]

Back to work............
OK about all we have left is to get our system some power! We need to feed a relay with 12V, then that 12V need to go to the rest of the system.

So we need a relay to power it all. I prefer a relay instead of trying to use the old scout wiring to power everything. Think of it as a "bright lights" kit for your motor!!!

Like I said before, I have 2 relays with this system. One is the fuel pump and the second was for the AC system.
When I checked the relay I found a couple of problems with it.
1. The wires are too small for the whole system.
2. This relay is only wired for the 87a terminal. This means the contact is only powered when the relay is off! When power is applied the relay energizes and open pin 87a....

Well that won't work for what I want to do.
So I have to rewire this relay!
It would have been easier to just use a new one but.... I can't find my spare. Somebody must have used it on another project!
Here is what it came in. Used to get them from Autozone for a few bucks.



Here is the GM bosch



I needed to remove a couple of the original terminals so I could replace them with larger wires.
A simple jewlers screwdriver and a pair of needle nose... and they are out.





Then poke a new hole in the seal to slip the wire thru.



Put the wire up thru the bottom and crimped a standard female spade on the wire!
Just to refresh your memory...87 is the output. 30 is the power in. 85 and 86 are the ground and the control wire to turn the relay on.
So I wanted a larger wire in 87 and 30!!
This is my wire for 87




This is the wire I will use for 30. It was the org wire that used to go to the oil pressure switch.



Not a good pic of the relay but you can see my notes!



Here is the new terminals installed.

[Bill usn-1]

Now what do I need to power with this new relay?
Well we need 12V to the coil.



We need 12V to the injectors. Remember that the 12V is always there with the key on and the ECM applys the ground to the inj to turn it on!



And how about the ECM!! Remember the pink with blk is supposed to be 12V when you turn the key switch on. Well this is how it gets it!
This was one of the wires that was removed from the connectors we cut off like the EGR...
You need to run the wires along the harness and up to the relay.



So we have 4 wires and only 1 terminal to connect them to. So we need to splice some wires together. This one way to do it.
Strip about 1/2" of insulation from around the main wire. I used the larger pink ignition wire as the main wire.



Then tin the wire by using a little flux and solder.



Then tin the smaller wire and then solder together.



Then I use heat shrink tubing over the connection to protect it! You can get these things at any wallmart or radio shack.
Do the remaining wires along the main wire. I don't put them all in the same place.



And here is where we are at. We have power to our system, I trimmed the grounds to the same length and put a new terminal on them. There are 4 gnds, 2 tan and 2 blk/wht on this harness. These go to a good engine ground point like a bolt on the back of the head!!


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[Bill usn-1]

Took a few more pics to help you see where the wires go!!!

A1-from the ecm to terminal 86 of the bosch fuel pump relay to energize the relay.



A4-egr optional
A5- Service engine soon (SES) light. This applies the ground to one side of the light. Use one of the leftover 12V pink/blk wires to provide the 12V to the other side of the light.



A6-12V switched, goes to the tie point of all the pink/blk 12v wires. Then up to the large pink ign wire that goes to the power relay terminal 87.





A8, A9 go to the ALDL connector (if you have 1). A8 to pin E, A9 to pin B, and a ground to pin A.



A10, B10, C9 will get hooked up to the scout (if applicable)



A11 ground goes to the tie point then out to most of the sensors for their ground. It ties to A12 inside the ECM then to ground.



A12, D1, D2, D6 ground to the tie point then to the main ground lug to the engine.

[Bill usn-1]

B1, C16 battery power to the tie point then up to the fuse.





B2 fuel pump relay terminal 87 on a bosch relay. Goes to a tie point. one wire to the fuel pump and the other to the relay.





B3, B5, D4, D5 to the EST connector.



B7 to the ESC if using a knock sensor.



B8 ties to the wire that energizes the AC compressor clutch so the ECM knows when it's on. Can also be tied to the OBA or OBW or to a switch for guys with a manual transmission so they can raise the idle while rock crawling to be able to use 1 foot on the brake and 1 on the clutch...no hand throttle needed!!

[Bill usn-1]

C3, C4, C5, C6 go to the IAC on the TB.



C10 to the temp sender.



C11, C14 to the MAP sensor.



C13, C14 to the TPS on the TB.



D7 to the O2 sensor.



D14, D16 to the injectors to provide the ground to turn them on.




And now the harness is about done till we lay it in the scout!!



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[Bill usn-1]

Not so fast big guy!!!!!

I decided I would show you guys how to test your system before it ever goes in your scout!! Then there can be no EXCUSES!!!

With the system layed out on the floor and everything still connected I grabbed my spare battery and my laptop.

I connected the red 12V wire and my green 12 Switched (relay) wire that will hook up to the the wire that went from the key to the original coil to the pos cable.

I ran a couple of ground wires to connect the distr and the coil to ground..remember the EST is mounted to the distr and it gets it's ground by being attatched to the motor.
Then I connected those grounds and the harness grounds to the neg cable.

I put a screwdriver in the end of the coil wire and set a ground wire from the battery about 1 1/2" away from the screwdriver....

Then I connected my laptop with my homemade ALDL cable to the A8 serial data wire and the ground.

Here's the system layed out...




Here's the actual connections. As soon as you hook up the relay power you will hear them click. If all is good, you should also see a blinking green 20 on the winaldl screen.



Here is the ALDL connections. Note only 2 wires are needed and I just use spade connectors for now. No ALDL plug with the system!!



Now do you want to see what happens when you turn the shaft of the distributor???







ZAP!!!!





Now that's a spark. Any doubt about the power of the newer Epoxy core coils?????
They will light you up!!!

But how do we know the rest of the system is working???

Well I'm glad you asked!

With the laptop hooked up I logged some data. Just the sensors.
Then I excersized each one and watched the numbers on the screen change.
I moved the throttle for the TPS.
I plugged a resistor into the CTS-temp sender wires to simulate a chage in temp(you could just unplug the sensor)
I applied vacuum to the map sensor hose and watched the numbers go down.
(how did I do that?..you will figure it out!)

I also used the resistor the MAT/IAT that the 6965 ECM uses.

When done I disconnected power then I plugged my 1227747 into the same wiring harness and retested everything!!

I'll attach the log files for you guys to look at in MS Excel format!

Now if you really wanted to go all the way!!!
Hook up your fuel pump to a can of fuel (outside).
Put the TB over a bucket.
Run the return back to the can.

Then when you first connect the relay power the pump should run for about 2 seconds then turn off.
Then when you turn the distr and produce a spark, the pump will come on and the injectors will shoot fuel!
Hook your drill to the distr and really have fun!!!

Now your entire system will be operational and checked prior to installing.
In open loop that is!!
Do you really want to put a torch to the new O2 sensor to get it up to 600* to see if the closed loop flag comes on???

I didn't think so!!


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