SOLVED -- 1993 3.0L Aerostar. The engine cranks but there's no spark.

[Mark McConnell]

The contradictions in tests results below indicate to me there is another factor that prevents an ICM from functioning when receiving the PIP signal during start-up.
(Attempting start-up...AKA, cranking the engine)

All the information I have read explaining how the Black CCD TFI ICM functions indicate it relies on the HAL sensor (PIP or crank sensor) during startup.

If the PIP signal is present and the ICM is good and has a voltage source, what would prevent the ICM from opening and closing the ground connection to the coil's primary?



First posted in July 2015 at fordforums.com

The vehicle:
1993 3.0 Aerostar
108,000 miles
Replaced the fender mounted ICM,(aftermarket & has no name on it) about 7 years ago and have not driven the van more than a half dozen times in the past 2 1/2 years...last driven about a year ago...Street into the driveway.

Current state: Cranks but no spark.

To trouble shoot the no spark issue I followed the instructions on:
Part 1 -How to Test the Ignition Coil (Ford 2.9L, 3.0L, 3.8L)
and
Part 1 -How to Test the Ford Ignition Control Module (Fender Mounted)
I followed all the Parts...

I get to the very last step which uses an LED test light.
Negative lead is connected to the PIP wire at the ICM.
The positive lead connects to Battery +.

I crank the engine and the LED blinks as the engine continues to turn over.
Prognoses: The ICM is bad.

OK.
I have a spare ICM & heatsink. (A motorcraft I picked up the last time I was at the salvage yard)
Lets put that in...and do the LED test...

I crank the engine and the LED does not blink as the engine continues to turn over.
Prognoses: The PIP is bad.

????

This method for testing the Aerostars PIP & ICM seems to be flawed...

...or is it just the owner?

Present day at explorerforum.com

After sitting for a year, I have returned to this headache.

Purchased:
New Distributor, battery, ICM and coil.
Have checked the wires and even bypassed part of the harness for a couple tests.

Current results:
PIP sends its signal to the ICM but the ICM does not appear to open the ground to the coil.
Have checked the ICM plug for continuity and appears to be fine.
ICM has Voltage or that is the plug end has voltage.
The ignition ground circuit checks.
Pin4 is connected to pin4, (ICM to PCM)

Continuity between the coil, distributor and ICM...battery...

In short, the troubleshooting procedure says replace the ICM.
So I bought a new ICM. The other 3 I have tried, (all used) may be bad...

Installed new ICM...
Cranks but no spark

There have been 3 occasions that it sounded like the Thrust I squirted was igniting. All before the new ICM.

Have checked my brain for loose connections...Appears connected due to an ability to write this post....

 

[BrooklynBay]

Welcome to this forum! Use a multimeter to test the resistance of the ignition coil. Did you check the cap & rotor for wear or damage?

 

[Mark McConnell]

New Distributor, battery, ICM and coil.
All have Zero miles.

Distributor (Cap, rotor, HAL sensor) purchased last month. The last test performed last July 2015 indicated a bad HAL sensor...
The test before that indicated it was a bad ICM because my LED test light flashed which indicated the PIP signal was present

The contradictions in results indicates, to me, there is another factor.
Still I bought a brand new distributor, I know it works. And yes, it flashes my PIP LED test light.

2 weeks ago I purchased a new ICM because the troubleshooting procedure indicated/says the ICM is bad.

The coil, I purchased last week after remote testing the old coil. Volt / Ohm meter tests were jumping. (intermittent issue maybe)
So I removed it and connected:

• battery + to primary +
• primary - to a foot -switch clip/conductor/line
• The other clip/conductor/line connected to battery -
• Coil wire to a gap-able spark tester
• Spark tester - clip to battery -

oh.... and a volt meter connected to the to the foot-switch's 2 lines.

Spark was intermittent at first and then ceased as the coil temperature increased.
So I purchased a new coil...and tested it with an ohm meter.

Discovered last night that I can have an ICM tested at the auto parts store. (imagine that, they were unable to test my coil but able to test my ICM)

So, I gathered up my collection of 4 ICM's.

• The one I purchased in 2007 (Was on vehicle when this no-spark started)
• The one I got at the salvage yard October 2014 when replacing missing dash and cab parts.
  
• The one I recently got at a wasp infested automobile graveyard last month
• and a BWD I purchased at O'reilly auto parts 2 weeks ago

...took them to O'reilly's and amazingly, they all checked good!
Crap! or Great...Great Crap!

So, where is the issue in this plethora of DC circuits mixed with enough digital to confine my van to a 1.5 Ton money ingesting, patience digesting, straw sitting on a camels back?

I am considering constructing a new harness between the distributor, coil and ICM. The one I have now is resembling a pin cushion from the numerous tests it has endured.

The Spark plugs have maybe 3000-40000 miles.
The Spark plug wires were replaced in 2007 when I installed the new ICM. That was about 15,000 miles ago...maybe 20,000...ehmmm, maybe.
The gas is...oh about... uhm. more than a year! This is why I have been using Starting fluid. After it wants to start I will remedy the gasoline situation if needed. (I did add some gas treatment last year when I had added some gas thinking it was out of gas possibly) (gas gauge floats on 1/8 of a tank when empty...I seem to recall)

 

[BrooklynBay]

Place the van in park, remove the distributor cap, then jump the starter solenoid relay on the inner fender wall. Check to see if the rotor is turning with the engine.

 

[Mark McConnell]

Okay.
The the rotor turns.

 

[don-ohio]

Doesn't that engine have the TFI MODULE on the side of the distributor? I haven't read everything here,cause I'm in a hurry. That is the cause of most loss of spark in my experience. don-ohio ^)

 

[BrooklynBay]

The later models relocated the module to the inner passenger side fender wall.

 

[Mark McConnell]

yep

 

[Mark McConnell]

After much deliberating I believe there is an intermittent issue in the wiring harness.
There must be. Has to be. Hopefully?

Thinking of doing a bench test with all my old parts connected and see if the spark tester sparks...without it connected to the PCM or any other part of the van.

Heck, if I fry an ICM I have 3 more.

Lets find out....


...................................

 

[Mark McConnell]

Unable to locate my old distributor I pulled my new one after removing the cap and capturing the position of the rotor.
Gathered up enough test leads and a couple of thin insulated crimp connectors. (female)

With the help of my Haynes filled in with colored markers schematic I carefully made the connections keeping in mind that I needed to be able to turn the rotor on the distributor.
I also connected a test light to the negative primary and battery positive.
Carefully took hold of the rotor and turned it a quarter and...guess what happened?

I heard, "spark spark" and saw the test light, "flash flash" in unison with the, "spark spark"

Conclusion:
It must be the harness

 

[Mark McConnell]

Update:
Unraveled the harness from the ICM to the fusible link that protects the ignition circuit/s.
It was looking pretty bad and was no longer fully insulated at the two ends of the undersized section of wire. (fusible link)

It broke as I was inspecting it.
Good sign? Possibly.
It looked as it had become deteriorated over time at the exposed ends. Saturation could had been occurring causing a hot resistance when current was flowing. This would explain why continuity measured normal. (If that makes sense. I have seen this occur in audio circuits. A bass speaker sounding as if it was clipping when the culprit was the lead inside the cabinet at the speaker terminal. It had been reduced to 3 unbroken strands.)

Corrected the issue. Dismantled the ICM Multi-pin plug and applied heat shrink to the wires with pin holes and carefully re-shielded the IDM and SPOUT wires.

Contact cleaner on all plug contacts, reassembled and....no spark.

After successfully recreating the bench test in the van, (spark) I introduced the other wires/circuits one by one until I achieved a no spark again. It's the SPOUT circuit!

I had spent many hours, (starting over a year ago) searching for the possible source of the no spark issue other than the coil, PIP, or ICM. And I recall reading about a month ago one suggestion to pull the SPOUT connector. ONE! And I don't think the person with the issue had tried it. His reply was similar to what I was thinking when I read that post. That's just to keep the timing from advancing when using a timing light.

Apparently someone knows something that most others do not. (Unless you are reading this now)

So,
The plan is to start the engine without the SPOUT connector and drive a couple of blocks to a mechanic and put it on a machine and determine the issue.

I had tried to thrust kick the thing once with no success and was out of time. Tomorrow I'll try again but will probably have to replace the fuel with some fresh stuff.

At least I have spark at the plugs again...

SOLVED!

Now I face an even more complicated predicament.
I'm not sure which end of the emotions pendulum I should be experiencing. Happy? or Angry!
If I could just stop the thing from swinging maybe I could achieve content and grateful.