JASONPCONKLIN

i have a chevy cammaro z28 1994 v8 5.7 L

Not Sparking problem

this is the entire history of this prob/solus EXPLANATION (my point of view)

its getting fuel i had an injector un pluged from engine to make shure, the engine turns over but wont start for 1.no spark 2 i have changed the folowing parts:

Spark Plugs, Spark Plug Wires, ICM Modual, ICM Coil, PCM (Computer), Starter, Fuses in side car and under hood, Fuel Pump,

a feand turns the key while i look at the meater conected to ground and the the wire i am checking

i have checked power in the wires every time the key is turned to start the car.....

i check power in coil wire ( pink ) that goes to the fuse that has 10 watts in the fuse box under the hood 12 volts... and i check power in the red wires from the coil to the ICM ignition Module 0 volts ... and i check the power in the WHITE wire that goes from the Module to the PCM (COMPUTER) 0.250 Volts ITS SUPOSED TO HAVE 12 OR SO VOLTS RIGHT? So i changed the PCM and transfered the KNOCK MODULE to the new PCM. THE WHITE WITE still has only 0.250 volts when the key is turned. so i found pictures of the PCM CONNECTOR "A" (RED) "B" (BLACK) "C" (GRAY/CLEAR) "D" (BLUE) these are the Documents: http://tinypic.com/view.php?pic=igj0o3&s=8#.VBpY80Ca9hI
http://tinypic.com/view.php?pic=23wr911&s=8
http://tinypic.com/view.php?pic=dha6ar&s=8
Image - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting

I HAVE USE THESE SHEETS TO FOLLOW WIRES TO THERE SORCES.

i started with the PCM CONNECTOR "B" (BLACK) and PCM CONNECTOR "D" (BLUE) THE BOXED IN PCM IGNITION FEED 439 PNK (PINK WIRE) ON BOTH SHEETS AT THE BOTTOM AND THE OTHER AT THE TOP... THEY LEAD FROM THE PCM TO THE MASS AIR METAL BOX SENSOR IN FONT OF THE ENGINE... I HAVENT CHECKED THIS WIRE FOR VOLTAGE READING (could this be the problem?) DOES IT SEND POWER TO THE pcm IF AIR PASSES THROUGHT IT? IN RETURN SEND POWER TO THE WHITE WIRE GOING TO THE IGNITION CONTROLE?

AFTER i checked the PCM BATTERY FEED 340 ORN (ORANGE WIRE) shown on the PCM CONNECTOR "B" (BLACK) in the middle and the bottom of the page... and they run togeter into the car from the computer through the car firewall on pasenger side and under the dash kick panels of the passanger and driver side to the fuse box on the side of the dash going to the left bottom corner side of the fuse box it has 12. volts going to the computer... SO THE WHITE WIRE SHOULD BE GETTING POWER TO SPARK THE SPARK PLUGS.
I HAVE A TEORY THAT I BELIEVE MAY WORK TO GET THE SPARK PLUGS TO SPARK: HERE IT IS: ON THE PCM CONNECTOR "A" (RED) SHEET BOXED IN RED AT THE BOTTOM TRACTION CONTROLE SYSTEM SPARK RETARD REQUEST... IF I SNIPPED / CUT THE WIRE WILL THIS MAKE THE SPARK PLUGS SPARK OR WILL THIS IN EFFECT CAUSE VITAL, MAJOR, ENGINE PROBLEMS?

also WHAT IS A POSIBLE SOLUTION TO THE SPARK ISSUE. ITS THE ONLY PROBLEM I HAVE THAT I CANT START THE CAR....

PLEASE HELP

Injuneer

At any point, have you scanned the PCM for codes?

Where are you checking for spark? You need to check at the spark plugs by pulling a wire and holding the end near a ground. If you have no spark at the spark plugs, you have to do the same check with the coil wire. Have you done ALL these checks?

How old it the Optispark distributor? What brand is it?

Not sure where you got an indication that the white wire from PCM pin B5 to ICM pin B should have 12V. This is a 0 - 5V pulse that tells the ICM when to fire the coil. Use this to verify the PCM is telling the ICM to fire the coil:

4th Gen LT1 F-body Tech Articles

You will find this:

The "10" on the fuse is not the rating in "watts".... it is the amperage that will cause the fuse to burn out to protect the circuit. In any case, it's good that you have 12V to the coil from fuse #11.

According to wiring diagrams in the factory manual, the ICM has 4 wires connected to it. None of them is red. The wire that runs from the coil, and supplies 12V to the ICM is pink/black and runs from the coil gray connector to the ICM pin A. You need 12V at the ICM end of that wire.

Go to Shoebox's site for the diagrams, pinouts, etc.

4th Gen LT1 F-Body Tech Aids

You theory about the pin A23 traction control spark retard request is not valid. Traction control was not available in the 1994 models, even though they show it in the factory manual. Cutting that wire (even if there is one there) will not do anything.

The PCM 12V feeds that you note in Connector "B" are supplying 12V to the PCM. If they weren't supplying 12V, nothing would work.

The only PCM wire that goes to the MAF sensor is the yellow wire from pin B19 to pin A on the MAF sensor. That has nothing to do with the spark system. The MAF measures the air flow into the engine, so that the PCM can add the required amount of fuel.

JASONPCONKLIN

Thanks so much for explaining all this detailed facts to me im now knoligable in this information