Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

1986 Ford Mustang 5.0


irsean's Avatar
Visiting Guest

Posts: n/a

06-25-04, 02:27 PM   #1  
irsean
1986 Ford Mustang 5.0

Runs for about 20 minutes then quits.
Not getting spark when quits.

Changed:
Ignition Control Module
Entire Distributor (Mag. pick-up unit and the reluctor)
Ignition Switch

Could this be the EEC or am I missing something?

 
Sponsored Links
Desi501's Avatar
Member

Join Date: Oct 2003
Posts: 2,207

06-25-04, 02:30 PM   #2  
Go a step farther and when it dies, see if you have power at one side of the coil. The EEC relay supplies power to the coil and is a frequent problem.

 
irsean's Avatar
Visiting Guest

Posts: n/a

06-25-04, 02:36 PM   #3  
irsean
Posted By: Desi501 Go a step farther and when it dies, see if you have power at one side of the coil. The EEC relay supplies power to the coil and is a frequent problem.
There is power to the powered side of the coil but no signal to fire from the negative side.

FYI: Coil was replaced as well.

 
Desi501's Avatar
Member

Join Date: Oct 2003
Posts: 2,207

06-25-04, 05:15 PM   #4  
Posted By: irsean There is power to the powered side of the coil but no signal to fire from the negative side.

FYI: Coil was replaced as well.
Are you sure it uses a magnetic pick up in the distributor and not a crank sensor. On some of those Fords, the dist pick-up's are actually Cam sensors and only fire and synch the injectors and not the coil.

 
slickshift's Avatar
Member

Join Date: Aug 2003
Posts: 4,320

06-25-04, 08:10 PM   #5  
This engine does not have a cam sensor

 
irsean's Avatar
Visiting Guest

Posts: n/a

06-25-04, 08:29 PM   #6  
irsean
Posted By: Desi501 Are you sure it uses a magnetic pick up in the distributor and not a crank sensor. On some of those Fords, the dist pick-up's are actually Cam sensors and only fire and synch the injectors and not the coil.
Yes, I'm sure.

 
Desi501's Avatar
Member

Join Date: Oct 2003
Posts: 2,207

06-26-04, 03:48 AM   #7  
Posted By: irsean Runs for about 20 minutes then quits.
Not getting spark when quits.

Changed:
Ignition Control Module
Entire Distributor (Mag. pick-up unit and the reluctor)
Ignition Switch

Could this be the EEC or am I missing something?
You've missed something in the primary system and it's not the computer. If your not losing power to the coil, then your losing reference signal. That can only come from module, pick up or crank sensor, the coil or related wiring. Since the fauilure seems to be timed, wiring doesn't seem real probable. I'll take a look at the circuit at work today.

 
irsean's Avatar
Visiting Guest

Posts: n/a

06-26-04, 10:02 AM   #8  
irsean
Thank you for your trouble.

 
Desi501's Avatar
Member

Join Date: Oct 2003
Posts: 2,207

06-26-04, 02:06 PM   #9  
As I thought, it's a very basic system. Coming off your ignition switch, make sure the W/PK wire has power in crank position, R/LG should be hot in run position. Make sure none of the plugs have melted. That's it for power supply. From there, it's just the pick up, module and coil. If you have a tach, try disconnecting it at the coil to make sure that's not interfering. That's one of the DG/Y wires at the neg side of the coil. Should be 2 that color. Three of the wires coming off the module are for the PIP circuit BK/O, Y/LG and DG. They should have no bearing on spark but you can remove the spout connector to bypass that circuit. Get a noid light and check for injector pulse while you have no spark. A bad Hall effect pick up will take out the injector pulse also. Double check again that you actually have 12v at the coil (not using a testlight) at the time you have no spark. Your overlooking something here.

 
irsean's Avatar
Visiting Guest

Posts: n/a

06-26-04, 10:21 PM   #10  
irsean
Will try this. Thanks a lot.

 
Search this Thread