found water on opti. replaced. no start, no spark, turns over, fuel good.
Going by the FSM I have no "service soon" light and no power on ignition feed wire #631 yellow to opti. Had since new so I've been down a lot of roads. Before I spend hours reading schematics has anyone got some input?
It was running strong, then died.
It's only been to a mechanic once when I had a no start. They said they found a broken circuit behind the dash but there was a blown fuse on the floor. Long time ago, before I got my first FSM.
Thanks
Till this is fixed I have to drive an '02 F150 so..............
** added...I checked ALL fuses and I own 2 ecm's.

 

Have you checked the coil ?

 

Do you know how to test for the A/C voltage drive from the ECM to the ICM. If you have drive voltage, then the ICM is probably bad. If you have no drive, then you're heading back to the ECM, opti, wiring and related items.

If you are unfamiliar with the procedure to check for drive, it's in the FSM but I can add a plain English procedure if needed.

 

test the ignition module my 93 did the same
thing it was the ignition module let us know
m kraz

 

You need to verify 12 volts is getting to the ECM
and the ECM ground wires are good.

Unplug ECM Green connector. Should measure 12 volts on
Pin 6 and Pin 17 both Orange wires. (Hot all the time).
Pin 18 Yellow wire. 12 volts for Optical sensor. (Hot when ignition is On).
Pin 12 Pink/Black wire. (Hot when ignition is On).

ECM has two main ground circuits.

G106 located engine block near oil filter.
Unplug Red ECM connector. Pins 17 and Pin 22 both Black/White wires.
should measure zero ohms to battery negative terminal.

G107 located transmission to engine bell housing bolt/stud driver side.
Red ECM connector Pin 6 tan/white wire.
Should measure zero ohms to battery negative terminal.

If power and ground wires are good when the ignition is turned On, the ECM
should ground one side of the Service Engine Soon indicator
turning it on. This is assuming the Cluster 5 amp fuse is good
along with the Service Engine Soon bulb.

 

Thanks to all for your input. Pcolt94 can you give me a page number in the fsm and yes pls supply a plain english version.
Hooked on Vettes...That is the type of info I was seeking. I will be checking all of it today.
Shoulda mentioned Auto Zone supplied a new control module due to a lifetime warranty.

If I solve the dead hot wire the rest will fall into place

Thanks again. I'll report back and/or seek more help

 

For the Distributor and ICM/Coil diagnostics, from a 94 FSM, book 2, 6E3-C4.

From Chart C4-A - page 2 of 2 for the OPTI --- which specifically notes with distributor connector disconnected, key on (but not cranking), with a test light, you should find it iluminates when touching the disconnected distributor connector wire harness's 'C' connector for circuit 631 (red wire for 94) and a good ground (with the other end of the test light).

If no light, faulty PCM connection, wire to PCM or faulty PCM.

So Jispr, as you mentioned the 'yellow' wire having no power, right from the beginning your OPTI was not the problem but upstream thereof (e.g. wires/PCM).

Using DVM on DC scale, measure voltage at distributor wire harness terminal 'A' and 'B', both should be about 5 vDC.

If no voltage, faulty PCM connection, wire to PCM or faulty PCM.

FROM CHART C4 - before doing any tests from chart C4 or C4-A, be sure to remove the tachometer filter from the circuit by disconnecting the 'gray' coil connector and jumpering 'B' terminal of the harness to the 'B' terminal of the coil (retains power to the coil but removes the tachometer 'filter' to prevent its damage).

Additional PCM tests can be performed after above to verify that there is a vAC of between 1 vAC and 4 vAC while cranking at the ICM (Ignition Control Module wire harness connector 'B' (and ground) -- this confirms the PCM is receiving a signal from the Distributor and thereby sending a signal to the ICM to fire the Coil. However, given the faulty 12vDC to the distributor, doubtful you would have this vAC, so test is moot.

 

Thanks Adm. That for later. Thanks to the input I now have a "service light" and power down the yellow to the opti. ECM fuse looked good but
wasn't. Still no spark..per timing light. But need to check the timing gun.
Wont start on fluid so...no spark. Have to wait till next weekend.

My Falcons lost but my Bulldogs go to SEC game!!!

Thanks all!!

 

In my 94 FSM, page 6E3-C4-5, chart C4 and related pages for ignition check tests.


Here are a few tests to get you started on the problem. Be the utmost of careful not to short anything to ground. ING key off, remove Ignition Control Module connector and check the ground connection on pin C (BLK/WHT wire), (resistance about 0) .

Next, “Key on”, check for 12 volts DC at pin A (PNK /BLK wire), and pin D, (Dark green wire). If no voltage check the coil fuse 10A, (#25), or wiring.

If all is good, set meter to read AC volts and connect probe to terminal B, (white wire). Have someone crank engine, meter reading should be between 1 to 4 volts. Key off.

If voltage OK, this indicates opti and ECM are probably working and the ICM is probable cause. The coil of course can be no good also.

If no AC voltage, opti, ECM or wiring could be source of problem.

 

They'll all lose to my Wildcats before the year is out.

 

Timing light? This isn't 1970, it has no business on a 93.
If your checking for spark, you need one of these. http://www.mechanicstoolsupply.com/H...r_p_17805.html

 

Basketball?

 

Hey a timing gun lights with spark. Worked in '70 works now. I aint checking timing just spark

 

There might be spark but of unknown quality. Weak or strong, the tester will find this out.

 

A final note...K.I.S.S. I caused all this. One week b4 this happened I wired a relay in place of the ecm controlled relay to 1 fan but did not quite finish the job. I used the ign wire from the old relay and the hot for the fan. Well the ign wire came loose, shorted it's fuse, the ecm fuse, and the coil fuse. At any rate all 3 fuses were dead and now my car is purring again. Many thanks for all the input!!