Losing Faith

[SledgehammerX]

Ok I have the color codes but only 5 wires on the box and from the harness so how do I wire it when the guide lists 6 wires :/

[FastWoman]

I don't have a good answer for you. There are different versions of the ICM, so you might not have the right one. Or you might have one from a different year that can be hooked up with 5 of the 6 wires. I don't really know the different variations of the ICM over the years. Once you pair up the colors that match, is there one color left over?

I'm afraid someone else is going to have to advise you from here. This is a job for Level III tech support!

[cozye]

Ok I have the color codes but only 5 wires on the box and from the harness so how do I wire it when the guide lists 6 wires :/

Page EE25

5 wires

Blue

Black

Black/white

Green

Red

[SledgehammerX]

Well I have checked and I have all the wiring correct now and still no spark, now I feel like I've hit a brick wall.

[SledgehammerX]

Cozye, is that the order it's supposed to be in from left to right if you're looking at it bolted back in the kick panel?

[Zed Head]

Ok so, I already have the FSM on my pc. I have no Internet so I'm using my iPhone. Upon looking at the FSM, it lists 6 wires to be plugged up on the ICM. I only have five. It states this G,R,L,BW,BW,B. I have a green, red, black, black with white stripe, and blue. So I'm a little confused

You said a 77 ICM, but what year is your car? 1978 only had five wires to the ICM, the five colors you listed. Maybe they went to 78 wiring in late 77? If you really only have five wires from the harness, then the 78 ICM would most likely work. Green and Red to distributor, BW is power to ICM and coil, B is ground and L (blue) is coil negative.

I might be wrong about using other ICMs in your car. 78 works in a 76 (if you leave out a pickup coil) and 76 would work in a 78 (with extra terminals left on the 76 ICM). But 77 has an extra power wire (BW) to the ICM (as you have found). It would take some study to figure out if it can be worked around.

But your five colors match 1978. If you have a 77 ICM and left one of the BW terminals unconnected, that could be your problem.

By the way, if you are looking at your Build Date to determine the year of your car, a late 77 Build would be an early 78 model.

Edit - I'm a slow writer. Reiteration - you might have 1978 wiring! If you have a module with a spot for BW (power) and it's not powered, it probably won't work. You need a module that will work with five wires. Probably 1978...

Edited December 14, 2010 by Zed Head

[SledgehammerX]

My ICM has an empty slot. If you actually look at the back of it it has only five wires running to it. This is a nightmare. The old ICM had an empty slot too.

[Zed Head]

If that is the case, then they probably just deleted one of the BW wires along the way, getting closer to the 1978 version.

But back to the reason for failure - did you determine why the first one failed? If your alternator is spiking out high voltage occasionally, it will toast a module immediately. If you had a cause for the first failure and did not find it/fix it, you might have just wasted another. A bad ground at the module can waste one also.

You weren't really clear on when the 20 minutes, then no start happened. Was that with the first one that failed, now you have a new one that has not worked at all? Or did one fail, then the new one ran for 20 minutes, now no spark.

It sounds like you were diligent with getting the right part and connecting it the same way. You should probably go back to the original problem when the first one died and see if you missed something.

Time for Christmas lights...

[SledgehammerX]

Ok! With wire tracing, I have spark again. Now it won't fire but still turn over. It turns over really fast and you can hear it combusting but it won't actually kick. Someone gr any ideas?

[Zed Head]

What was the problem? Details please...

[cozye]

After details, now that you have spark, you need to go through the EFI section of the FSM and use the multimeter to test all inputs and voltages for the 35 pin ECU connector. This will rule out any ECU or EFI problems.

[FastWoman]

... but before you do that, you might want to spray a bit of starter fluid into your intake and try starting the engine. If your engine mechanicals and your ignition are right, the engine should start, run very briefly, and then possibly die (or not). This is not to say it will run WELL, but it should still fire up. If this happens, your ignition is working, and you can move forward.

BTW, one thing to check is the connection between the (-) post on your ignition coil and the #1 terminal on your ECU. Without that connection, your ECU will not deliver fuel, and your engine won't run.

Edited December 15, 2010 by FastWoman