Ignition issues

Hey guys... I bought my son a 1992 bronco Eddie Bauer several months ago & it ran perfect for awhile but it began to act up a month or so ago. It started shuttering like it needed gas so we replaced the fuel pump. Ran good for awhile & started missing again. It only did this once it was driven for a while. Long story short, we've replaced ICM, distributor, rotor, cap, & coil. I'm just lost as to what it could be. Any help would be greatly appreciated.

Yo jvinson,

Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe @

http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded

Some basics;

The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test.

Run it around to heat the engine up and shift thru all gears including Reverse.

Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual & release clutch.

Then turn off engine, all accessories/lights (close driver's door) , etc.

Do KOEO test First

Post Code(s) here according to:

KOEO

&

KOER

...

Without a code;

Any idea of when fuel filter was last replaced?

Is air filter ok?

Check for vacuum leaks, see my leak test in post #20 @

http://broncozone.com/topic/23994-90-58l-getting-continuous-code-33-and-running-code-44/?p=125535

Any fuel quality concerns? Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.

Any arcing around spark plugs or wires when viewing at night?

Has plug wires been replaced before this occured?

Read this... http://www.prestolitewire.com/pages/diagnostic_tips/56.php

...

We would try this but only issue would be we have no spark coming from coil. Tried a inline spark tool earlier & nothing from coil to distributor.

Have you tried replacing the wire from the ignition coil to the distributor cap?

Maybe a stupid question but which wire? He has a 3 wire plug, 2 go into coil, & one goes out to the side of the coil to a small round cylinder. Looks like a resistor or something.

I'm not 100% sure I need to go check on my truck in the morning. It's been a while since I've replaced all that on my 95.

I wonder if the trouble is in the key switch? We bought it from a friend of ours & her dad rigged it up so he could start it without the keys.

Yo,

resistor is the Radio Noise Suppression Capacitor

Ignition Wiring Diagram @ http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=33067

You can still do the KOEO portion of the Self Test for codes.

As long as engine will crank the engine over;

How to Troubleshoot a No Start (Ford 4.9L, 5.0L, 5.8L) @

http://troubleshootmyvehicle.com/ford/4.9L-5.0L-5.8L/how-to-troubleshoot-a-no-start-1

Cool... Heading to try that now Miesk5. I'll let y'all know here in a few. Thx

Yo,

OK,

The no key hack and chop may be the issue.

But almost impossible to diagnose from here.

Start Wirng Diagram for the 92;

@ http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=9235

More @ http://www.revbase.com/BBBMotor/Wd

....

Switch Removal & Installation in 92 to 96 ; "...Removal; Disconnect battery ground cable (14301). Remove the upper steering column shroud (3530) by removing the self-tapping screws. Remove four bolts retaining lower steering column shroud and remove lower steering column shroud. Remove lock ***** and disconnect the ignition switch electrical connector. Rotate the ignition switch lock cylinder (11582) to the RUN position. Remove the two screws retaining ignition switch (11572). Disengage the ignition switch from the actuator. Installation; NOTE: A new replacement ignition switch assembly will be set in the RUN position as received. Adjust the ignition switch by sliding the carrier to the RUN position. Make sure the ignition switch lock cylinder is in the RUN position. The RUN position is achieved by rotating the ignition switch lock cylinder approximately 90 degrees from the LOCK position. Install the ignition switch into the column actuator hole. It may be necessary to move the ignition switch back and forth slightly to align the ignition switch mounting holes with the lock cylinder housing threaded holes. Install retaining screws. Tighten to 6-8 Nm (53-71 lb-in). Connect the electrical connector to the ignition switch. Tighten lock ***** to 0.8-1.3 Nm (7-11.5 lb-in). Connect battery ground cable. Check ignition switch for proper function, including START and ACC positions. Also, make certain that the column is in the LOCK position. Install the upper steering column shroud and lower steering column shroud..."

Ignition Switch Pin-Out Diagram & Continuity Testing (Logic Tables) 92-96

http://www.supermotors.net/registry/media/831772

My truck just has a wire going from the top of the coil to the center of the cap.

Yo,

That wire is a thick one similar to the spark plug wire.



This is a red MSD Coil, similar to original Motorcraft.

Finally found a pic from our 96, high tension wire to distributor is at front of coil

Yo,

That sounds like the old tubular type coil you have.

Here is another pic from an 85 Bronco



by Daniel T.

We tried the test on the ICM & it was bad. It has me clueless cause it's brand new

Yo, if it Not a Motorcraft ICM, suspect bad quality.

Did you use the thermal grease, if supplied with the icm?



Or



Or



Coat ignition control module baseplate with silicone compound, approximately 0.0179mm (1/32-inch) thick. Use Silicone Dielectric Compound (WA-10) D7AZ-19A331-A or equivalent meeting Ford specification ESE-M1C171-A.

Position ignition control module onto heat sink and tighten two retaining screws to 1.2-1.8 Nm (11-16 lb-in).

Install ignition control module heat sink assembly on left fender apron using two retaining screws, and tighten to 9-14 Nm (80-124 lb-in).

Connect wiring to ignition control module.

http://www.diesel-dave.com/vehic/manual/stj/images/b5728a.gif

Yeah, we used the grease. I guess we just received a bad ICM

Well guys, everything we've replaced hasn't worked. Kinda lost now. Any ideas would be great.

Yo jvinson,

Try the Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe @

http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded

Since it will not start, do the KOEO test.

But engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test

If too cold there, place a space heater near radiator and channel heat using metal trash cans, etc.

and if it can start later, greater than 180° F for the Key On Engine Running (KOER) Self-Test.

With the ignition key hack, I can't offer anything more other than to strip the previous owners wiring mess off, installing new key cylinder, etc. Then testing to get it to turn over then testing using the How to Troubleshoot a No Start (Ford 4.9L, 5.0L, 5.8L) article.

Will look at wiring diagrams for start, run, etc later.

Yo J,

Look at this coil test

http://troubleshootmyvehicle.com/ford/4.9L-5.0L-5.8L/how-to-test-the-ignition-coil-1