Ok, i think the wire i've been hunting down for a while goes to the electronic spark control module (two prong connector, black wire & pink with black stripe wire). Where is the ESC module located?
87' 350 TPI

Thanks
JP

 

The ESC module will be located on drivers side firewall in/around the relay rack. Between P/B booster and fender. It is a 3 x 3" and 1/2" (approx) black box with three large letters on the label (such as HKR). five pin connector with 4 wires.

RBob.

 

Hmmmm, my Chilton says the one wire (white) knock sensor and a two wire (black & pink with black stripe) connector goes into it. Now i'm confused.

 

The pink/blk. stripe wire indicates it is an ign. on wire(12 volts)
the blk. wire then supplies the ground from the computer. So use an ohm meter and back track it to the computer to see what pin it hooks to, that will tell you what it goes to.

 

See i can't get my new engine to start, could this be the problem? How can i tell what pin it is from the resistence?

 

You only use the ohm meter to find which wire is going to the computer(continuity test). That plug would be something that operates a solenoid, like the EGR or Canister etc. It won't have anything to do with starting the engine.
Connect one wire of the ohm meter to the blk. wire and then probe all the blk. wires at the computer 'till you find the one that registers on the meter.

 

Ok, i found the esc module and there is a 5 plug connector. Rbob, you were right, sorry. Two of the four wires are the pink with black stripe and the black wire. So I found one end of these wires. Supposidly the other end goes to the ecm. The black one should go to B7-C1 in the ecm and pink with black stripe goes to A6-C1 (or maybe it is A8-C1, i can't tell) The problem is this loose connector will never reach the ecm, so where does it connect to eventually reach the ecm? The connector is in the red circle in the pic.
Thanks
JP

 

I think you need the runners and plenum to get the engine to run? OK, ok, bad joke. . .

The ESC module won't keep the engine from running. Can unplug it and all you will get is a SES light. I am not that familar with the MAF TPI wiring. . .So, I do recall that the MAT sensor is in the rear of the plenum, that is a 2 pin conn. There is also the EGR that needs to be hooked up (conn to a vac solenoid and a conn to the temperature probe?).

The EST (electronic spark timing) module is in the distributor. That gets two connectors, a 4 pin to the ECM and a 2 pin to the coil.

Isn't there an oil/fuel-pump switch on the back of the block? Or is it at the oil filter?

Hope someone else recognizes the conn's in the pic. . .

RBob.

 

FWIW, I have an '87 Z, and there is a connector on the harness in about the same area that doesn't connect to anything. I've never found out what it is supposed to be connected to, but the car ran OK without it plugged in. I mistakenly tried to use that connector before on the MAT sensor pigtail, before I realized that that wasn't the right one. I don't remember the colors of the wires though.

If you're having trouble getting it running, double check all of your other connections, and make sure you're distributor is set up right. And triple check vaccuum hoses, one small leak and the car will have a tough time idling. I've had issues where the hard line to the canister kept popping off, and it wasn't clear why the engine wouldn't idle, until you looked down in front by the headlight and saw that line disconnected and a big ol vaccuum leak.

 

Ok, thats interesting about your '87 Z. I have all the other connections connected, i check 7-8 times, including the others in the pic. The yellow circle goes to the egr solinoid. The blue circle goes to the connector above the oil cooler. I guess its possible my engine builder gave me the engine on #1 exhaust stroke instead of compression and therefor i don't have timing right. But i would think they wouldn't make a mistake like that, i guess i will check it. Also, can timing be set while cranking the engine?

 

Not very easily if at all

cranking is such a low rpm that the flash of a timing light isn't much to work with.

 

But i should be able to get it close enough to get it to start, right?

 

If you just want it to start get a buddy to crank the engine, disconnect the EST, and turn the distrib back and forth untill you find the "Sweet spot" sometimes numbers isn't what it takes to get it to fire, so just move the distrib to where it wants to be, then go from there.

 

you will definitely need to verify that you are on #1 compression stroke, then set the distributor up so that it's close.

couple ways to do that, w/o taking too much stuff off:

-either pop off valve cover and watch valvetrain, when TDC comes up, and you continue past, if exhaust valve starts moving, you are on compression stroke.

-remove #1 plug, while cranking in short bursts up to TDC, put your finger over the hole, when compression blows finger off, you're on compression.

you always have to double check an assembled motor, since most times, you align the timing dots at the #6 firing position(dots close together; top of crank, bottom of cam gears), then valves are adjusted, depending on methods, you can end up on #1 or #6.

once you find that, you can get cose enough to fire and time by putting the #1 cylinder plug wire post on the dist cap aligned with the rotor tip. Hope that helps....... if you're already aware of this stuff, then its just a sanity check.

 

Actually i tried that, couldn't get it to fire up. We didn't disconnect est, how would that make a difference? I'm begining to think the dist is 180 off.

 

Maybe my engine builders put it on #6 by accident. If this is true, i'm getting a little nervious about my engine.

 

even if the engine was 180 deg off the car should at leat try to start and even run but very badly. Just went through all of this myself. make sure the fuel pump is running and dist. is timed to the #1 cylinder on compression stroke and rotor is pointing to #1 cap wire. if the chain was set 180 off I konw on the cfi 305 you can set it off of #1 or #6 depending on the cam/crank relation

 

If it is timed on #1 compression the dizzy wouldn't be 180 off. I'm getting fuel.

 

I got it running today. It turned out that the engine wasn't at TDC when the machine shop gave it to me, it was #6 tdc. So thanks everyone for all your help. It sounds great right out of the y-pipe.
JP

 

RBob.