How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask SMTBob Your Own Question

SMTBob
SMTBob, Senior Master Ford Technician
Category: Ford
Satisfied Customers: 114
Experience:  30 years experience,Ford factory trained automotive and diesel technician,ASE and Ford Certified
Type Your Ford Question Here...
SMTBob is online now
A new question is answered every 9 seconds

92 F150: Ive replaced ICM, PCU, Coil..Ignition Switch..distributor

Customer Question

92 F150 5.0l with intermittant, now constant ignition problem. I've replaced ICM, PCU, Coil, Ignition Switch and PIP unit in the distributor. I've done voltage & continuity checks of the wiring recommended by the Haynes manual and replaced the ICM connector too with no real problem found. I tried shorting the pins 1 & 2 on the ICM connector (with ICM disconnected) to see if i could get the coil to fire with no luck. I'm open to any suggestions.
Submitted: 3 years ago.
Category: Ford
Expert:  SMTBob replied 3 years ago.
Chat Conversation Started
SMTBob :

I am here to help.If you are getting no spark and have already tried all of those things-the only thing I have for you is a diagnostic path to follow out of the 92 F150 PCED.Here it is:










1992 PCED On Board Diagnostics I A


SECTION 8A: Ignition System Diagnostic Procedures




A: Distributor Mounted TFI-IV No Start




A1 WERE TESTS IN EEC-IV QUICK TEST COMPLETED


Were all tests accomplished according to EEC-IV Quick Test procedures?











Yes No
GO to A2 .REFER to Section 2A , Diagnostic Routines.


A2 CHECK FOR GOOD BATTERY


Is battery voltage greater than 12 volts DC with the key on?











Yes No
GO to A3 .SERVICE battery.


A3 CHECK FOR SPARK AT COIL DURING CRANK



  • Using an Air Gap Spark Tester (D81P-6666-A) or a Neon Bulb Spark Tester (D89P-6666-A) or equivalent, check for spark during crank at coil wire.


Was spark present during crank?











Yes No
GO to A9 .GO to A4 .


A4 CHECK FOR TFI POWER



  • Key off.

  • Connect TFI diagnostic harness to EEC breakout box, connect BAT- lead to negative post of battery, and connect TFI module tee to TFI module and vehicle harness.

  • Do not connect BAT+ lead of TFI diagnostic harness to battery.

    [IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]100[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE] CAUTION: Do not connect EEC processor to EEC breakout box when it is used with TFI diagnostic harness.



  • Make sure PIP OPEN/NORMAL/SPOUT OPEN switch on TFI diagnostic harness is in the NORMAL position.

  • Use TFI overlay on breakout box.

  • DVOM on 20 volt DC scale.

  • Key on.

  • Measure voltage between J5 (TFI PWR) and J7 (BAT-) at breakout box.


Is voltage greater than 10 volts DC?











Yes No
GO to A5 .SERVICE power open to TFI module in harness or connector. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A5 CHECK FOR PIP SIGNAL



  • DVOM on 20 volt AC scale.

  • Crank engine and measure voltage between J15 (PIP) and J7 (BAT-).


Is voltage between 3.0 and 8.5 volts AC?











Yes No
GO to A6 .GO to A11 .


A6 CHECK FOR SPOUT SIGNAL



  • Crank engine and measure voltage between J10 (SPOUT) and J7 (BAT-).


Is voltage between 3.0 and 8.5 volts AC?











Yes No
GO to A7 .GO to A15 .


A7 CHECK VBAT AT COIL



  • Key off.

  • Connect diagnostic harness coil tee to vehicle harness; do not connect diagnostic harness to coil.

  • Key on.

  • DVOM on 20 volt DC scale.

  • Measure voltage between J2 (VBAT C) and J7 (BAT-).


Is voltage greater than 10 volts DC?











Yes No
GO to A8 .SERVICE power open to coil in harness or connector. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A8 CHECK FOR COIL- SIGNAL



  • Key off.

  • Connect BAT+ lead of TFI diagnostic harness to positive post of battery.

  • Connect 12 volt incandescent test lamp between J1 (BAT+) and J3 (COIL-).

  • Crank engine.


Did test lamp flash brightly?











Yes No
REPLACE coil. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.GO to A23 .


A9 CHECK FOR SPARK AT ALL WIRES



  • Using an Air Gap Spark Tester (D81P-6666-A) or Neon Bulb Spark Tester (D89P-6666-A) or equivalent, check for spark at all wires.


Was spark present at all plugs during crank?











Yes No
GO to A10 .SERVICE distributor cap, rotor, plugs or plug wires. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A10 CHECK PLUGS



  • Remove and check plugs for damage, wear, carbon deposits and proper plug gap.


Are plugs OK?











Yes No
Not an Ignition problem, REFER to Section 2A Diagnostic Routines.SERVICE plugs. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A11 CHECK FOR PIP FROM TFI



  • Turn switch on diagnostic cable to PIP OPEN.

  • DVOM on 20 volt AC scale.

  • Crank engine and measure the voltage between J15 (PIP) and J7 (BAT-).


Is voltage between 3.0 and 8.5 volts AC?











Yes No
GO to A12 .GO to A14 .


A12 CHECK FOR PIP SHORT HIGH IN HARNESS



  • Key off.

  • Turn switch on diagnostic cable to NORMAL.

  • Disconnect EEC processor.

  • DVOM on 20 volt DC scale.

  • Disconnect diagnostic harness TFI module tee from TFI module only; leave TFI module tee connected to vehicle harness.

  • Key on.

  • Measure voltage between J15 (PIP) and J7 (BAT-).


Is voltage less than 0.5 volts DC?











Yes No
GO to A13 .SERVICE PIP between EEC processor and TFI module in harness for short high. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A13 CHECK FOR PIP SHORT LOW IN HARNESS



  • Key off.

  • DVOM on 20K ohm scale.

  • Measure resistance between J15 (PIP) and J7 (BAT-).


Is resistance greater than 10K ohms?











Yes No
REPLACE EEC processor. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.SERVICE PIP between EEC processor and TFI module in harness for short low. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A14 RESISTANCE CHECK OF TFI MODULE



  • Key off.

  • Disconnect diagnostic harness from TFI module.

  • Remove TFI module from distributor.




























    Measure the resistance between:Is the reading:
    PIP IN and PIP OUTless than 150
    PIP PWR and TFI PWRless than 150
    GND and PIP INgreater than 500
    GND and IGN GNDless than 5
    PIP PWR and PIP INbetween 900 and 1.5K



Are readings OK?


[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]325.82781456953643[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]












Yes No
CHECK stator and wiring inside distributor, if OK REPLACE PIP sensor. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.REPLACE TFI module. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A15 CHECK FOR SPOUT IN HARNESS



  • Turn switch on diagnostic cable to SPOUT OPEN.

  • Crank engine and measure voltage between J10 (SPOUT) and J7 (BAT-).


Is voltage between 3.0 and 8.5 volts AC?

Note: Engine may start, continue diagnostics.












Yes No
REPLACE TFI module. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.GO to A16 .


A16 CHECK FOR SPOUT HIGH



  • Key off.

  • Disconnect diagnostic harness TFI module tee from TFI module only; leave TFI module tee connected to vehicle harness.

  • Turn switch to NORMAL on diagnostic harness.

  • DVOM on 20 volt DC scale.

  • Key on.

  • Measure voltage between J10 (SPOUT) and J7 (BAT-).


Is voltage less than 0.5 volt DC?











Yes No
GO to A18 .GO to A17 .


A17 CHECK FOR SPOUT SHORT HIGH IN HARNESS



  • Key off.

  • Disconnect EEC processor.

  • Key on.

  • Measure voltage between J10 (SPOUT) and J7 (BAT-).


Is voltage less than 0.5 volt DC?











Yes No
GO to A20 .SERVICE SPOUT between EEC processor and TFI module in harness for short high. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A18 CHECK FOR SPOUT SHORT LOW



  • Key off.

  • DVOM on 20K ohm scale.

  • Measure resistance between J10 (SPOUT) and J7 (BAT-).


Is resistance greater than 10K ohms?











Yes No
GO to A20 .GO to A19 .


A19 CHECK FOR SPOUT SHORT LOW IN HARNESS



  • Disconnect EEC processor.

  • Measure resistance between J10 (SPOUT) and J7 (BAT-).


Is resistance greater than 10K ohms?











Yes No
GO to A20 .SERVICE SPOUT between EEC processor and TFI module in harness for short low. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A20 CHECK FOR PIP OPEN IN HARNESS



  • Key off.

  • DVOM on 200 ohm scale.

  • Disconnect EEC processor.

  • Measure resistance between Pin 56 (PIP) of the EEC processor harness connector and J15 (PIP) at the breakout box.


Is resistance less than 5.0 ohms?











Yes No
GO to A21 .SERVICE PIP open between EEC processor connector and TFI module in harness. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A21 CHECK IGN GND AT EEC PROCESSOR



  • Reconnect diagnostic harness TFI module tee to TFI module.

  • Measure resistance between Pin 16 (IGN GND) of EEC processor harness connector and J7 (BAT-) at the breakout box.


Is resistance less than 5.0 ohms?











Yes No
REPLACE EEC processor. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.GO to A22 .


A22 CHECK FOR IGN GND OPEN IN HARNESS



  • Disconnect diagnostic harness TFI module tee from TFI module only; leave TFI module tee connected to vehicle harness.

  • Measure resistance between Pin 16 (IGN GND) of EEC processor harness connector and J9 (IGN GND) at the breakout box.


Is resistance less than 5.0 ohms?











Yes No
REPLACE TFI module. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.SERVICE IGN GND open between EEC processor and TFI module in harness. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A23 CHECK FOR COIL- OPEN IN HARNESS



  • Key off.

  • Disconnect diagnostic harness TFI module tee from TFI module only; leave TFI module tee connected to vehicle harness.

  • Disconnect BAT+ lead of TFI diagnostic harness from battery.

  • DVOM on 200 ohm scale.

  • Measure resistance between J3 (COIL-) and J4 (TFI COIL-).


Is resistance less than 5.0 ohms?











Yes No
GO to A24 .SERVICE open coil- between TFI module and coil in harness. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A24 CHECK FOR COIL- SHORT LOW IN HARNESS



  • Key off.

  • DVOM on 20K ohm scale.

  • Measure resistance between J3 (COIL-) and J7 (BAT-).


Is resistance greater than 10K ohms?











Yes No
GO to A25 .SERVICE coil- short low in harness between TFI module and coil. Coil may be damaged. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.


A25 CHECK FOR COIL- SHORT HIGH IN HARNESS



  • DVOM on 20 volt DC scale.

  • Key on.

  • Measure voltage between J3 (COIL-) and J7 (BAT-).


Is voltage less than 5.5 volts DC?











Yes No
REPLACE TFI module. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.SERVICE coil- short high in harness between TFI module and coil. REMOVE all test equipment. RECONNECT all components. CLEAR Continuous Memory. RERUN Quick Test.






SMTBob :

Thats the best I can do for you.I hope that helps.SMTBob

Customer:

I don't have any details on the quick test procedure that's mentioned in your text. I've done most of the other tests that you've suggested, but I didn't have some of the measurements you listed for testing the ICM. Also how do you clear the continuous memory?

Customer:

I've got a buddy with a good Fluke scopemeter and i plan to take a close look at the PIP input and SPOUT signals. on my fluke 77 they're bouncing between 4-5.5 VAC.

Customer:

So how do i print the text of your answer?






SMTBob, Senior Master Ford Technician
Category: Ford
Satisfied Customers: 114
Experience: 30 years experience,Ford factory trained automotive and diesel technician,ASE and Ford Certified
SMTBob and 8 other Ford Specialists are ready to help you
Expert:  SMTBob replied 3 years ago.

I only know how to clear the continuous memory with a STAR II EEC IV scanner because that is all I have ever used on that year model.You would have to follow the instruction of the particular scanner you are using if it is capable of clearing codes.The only way I can tell you to print the info is to right click your mouse and then click Print on the list of options.Good luck.

The quick test procedures are basically retrieving codes KOEO and KOER.

Expert:  SMTBob replied 3 years ago.
The SPOUT and PIP values are supposed to be measured in RPMs using an EEC IV monitor and are supposed to match @ 110-150 RPMs cranking.Since you dont have a EEC IV monitor and that is 20 year old equipment-its going to be tough for you to check.The easiest way to check the entire TFI/PCM/Stator together is to see if you are getting voltage at the tach side of the coil out of the TFI module.Try this-
RESISTANCE CHECK OF TFI MODULE
  • Key off.
  • Disconnect diagnostic harness from TFI module.
  • Remove TFI module from distributor.

    Measure the resistance between:Is the reading:
    PIP IN and PIP OUTless than 150
    PIP PWR and TFI PWRless than 150
    GND and PIP INgreater than 500
    GND and IGN GNDless than 5
    PIP PWR and PIP INbetween 900 and 1.5K

Are readings OK?

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
< Last | Next >
  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
  • Because of your expertise, you armed me with enough ammunition to win the battle with the dealer. They are installing a fuel filter and fuel pump at no charge to me. Molly USA
  • I needed help with my car on Saturday morning....got a response in 5 minutes, and it was the perfect solution. Thanks again to your service. Jason V. Kirkland, WA
  • I do know, after going though this with JustAnswer, that I can somewhat trust my mechanic but I will always contact you prior to going there. BR New Jersey
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
 
 
 

Meet The Experts:

 
 
 
  • Ron

    ASE Certified Technician

    Satisfied Customers:

    20942
    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
< Last | Next >
  • http://ww2.justanswer.com/uploads/FO/fordguy4u/2011-12-17_222940_HPIM1257.64x64.JPG Ron's Avatar

    Ron

    ASE Certified Technician

    Satisfied Customers:

    20942
    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka- Moose)'s Avatar

    Chris (aka- Moose)

    Ford Technician

    Satisfied Customers:

    22382
    16 years experience with Ford.
  • http://ww2.justanswer.com/uploads/JM/jmcdo28/2012-2-23_01655_resized.64x64.jpg John Mc's Avatar

    John Mc

    Ford Technician

    Satisfied Customers:

    5493
    19 years Ford Lincoln Mercury experience
  • http://ww2.justanswer.com/uploads/wmarti7/2009-4-18_04332_Avatar.jpg Chuck's Avatar

    Chuck

    ASE Certified Technician

    Satisfied Customers:

    1684
    33 Years Experience,Ford Senior Master,ASE Master,L1 Advanced Engine Performance
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    1518
    12 years at a Ford Lincoln/Mercury and Jaguar dealer as a technician and shop foreman.
  • http://ww2.justanswer.com/uploads/BA/baddad1/2014-4-1_23659_avatar.64x64.jpg Mike V.'s Avatar

    Mike V.

    Auto Service Technician

    Satisfied Customers:

    789
    25 years experience on all makes and models, Licensed NYS Inspector.
  • http://ww2.justanswer.com/uploads/lostrider/2009-9-26_23144_php4VNWAA_c1PM1.jpg lostrider's Avatar

    lostrider

    Ford Technician

    Satisfied Customers:

    2940
    ASE Master Technician, Ford Senior Master Technician,Diesel certified, ASE Master, 22 yrs FORD exp.