The harness wires are pink yellow and purple. Also getting 12 volts to the pink wire.

That pink wire on the connector should attach to pink on the harness heading to the engine computer. The blk/wht wire in the middle should attach to purple on the harness and the yellow on the left should attach to yellow on the harness. Is that what you have?

George

Yes that is correct. But I have no pulse. Maybe I need to check out the coil, ign module and crank sensor. Checked these before and replaced the coil and module as the coil was bad but I replaced both.

Here is the sequence to get ignition/fire to your plugs. Finding out what's wrong involves checking the output at each step to see where the signal pulses no longer exist and then figuring out why there is a break in the sequence. It doesn't matter what end you start with but for the shade tree mechanic working backwards from the plugs towards the crank sensor is easier. Do you have an led test light and does your digital meter have AC volts on it?

https://cimg5.ibsrv.net/gimg/blazerf...58a89675c3.jpg


George

Okay I got power to the pink wires at all plugs. Started at the dist pink show 13.01, checked the others on ac on meter, .00 on both wires
coil pink 13.01.
O0 on white. Module 13.02 pink and yellow
06, blk 00. W/b 27.9. cps 13.02 other two
00. Where on the computer do I check.

There is no value in testing AC voltage on DC battery voltage, all voltage tests need to be on DCV.

Just to confirm. With key on and everything connected, you have 12V or more on the coil pink wire, the ICM pink wire nd the crank sensor pink wire? If that is correct then one more voltage test. Key on, everything connected and measure the ICM voltage between the pink wire and the ground blk/wht wire on the ICM, not frame or battery ground. If that is good then we move on to find out where the pulses have failed. You need an led test light like this:




Which we will use to check for pulses out of the engine computer to the ICM and from the ICM to the coil. Then if thats good then we will need to check for pulses out of the crank sensor which is trickier and so I am saving that for last.

Look at live data on your scan tool and tell me if the rpms register when you crank the engine.


George

Thanks for being so patient with me as I am pushing 80 and I have to study things a little longer lol. Okay, I rechecked the voltage at the plugs. The cps pink wire 12.95, purple .04, y.03. Module pink 12.87, white. 44, blk. 04, w/b
00. Coil is pink 12.86, w/b .00. Dist the wires are to fade to tell but I will list them as ABC
A- pink 12.94, B, .04, C .03. I also get 12.87 on Module with Coil plug in, on module w/b wire. I hooked up the scanner and it responds was (unable to establish communication). Thanks papajim

No problem, gettin' old aint' for sissies (ask me how I know).

So far the pink wires look good.

Did you do the test where you put the meter test leads across the power and ground wires on the ICM?

Do you have an LED test light yet so we can test for pulses?

George

Yes the test on the imc was 12.84. And yes I have a new test light.

is it an led or old school incandescent test light?

George