HELP. I have a problem with my 86 ranger 2.9 not running right

[JustinWaggoner98]

Hi I have an 86 ford ranger 4x4 with the 2.9 v6. I cant seem to figure out why it won't run right. It acts like all of the power to motor just dies, It cuts out while its running. Its not like a miss on one cylinder but all of them at the same time. Just all power quits at once and them comes back
I've replaced:
map sensor
throttle positioning sensor
Cap and rotor
Plugs and plug wires
Fuel pressure sensor/regulator
Both fuel pump on frame and in the fuel tank
Fuel filter
Egr value sensor
Injectors
Air filter
O2 sensor
Coil
If anyone can help me I'd be much appreciated.

 

[franklin2]

One thing you haven't replaced, the TFI module mounted to the side of the distributor. They are known to fail frequently. Make sure you clean the mounting surface off good and put lots of heat sink grease on it.

 

[JustinWaggoner98]

One thing you haven't replaced, the TFI module mounted to the side of the distributor. They are known to fail frequently. Make sure you clean the mounting surface off good and put lots of heat sink grease on it.

I have also replace the tfi as well. And it still has the issue

 

[RonD]

Is there any sign of losing 12volt power on the dash gauges when this happens?

If not then there are just 2 relays in the engine bay that can cut "power" to the spark and fuel systems without effecting dash gauges
EEC relay, has a brown base, if powers the fuel injectors and computer

Fuel Pump relay, it powers the fuel pump, of course, lol, it has a Green base

Picture here if these 2 relays and the colors: https://www.therangerstation.com/forums/index.php?attachments/img_20191215_230228-jpg.34656/

Inspect the wiring in the bases as they can corrode inside
You can unplug either relay while engine is idling and see if that mimics what you feel when driving

And the problem may be 1 wire, to spark system or fuel system, that intermittent, and that will be very very hard to track down

 

[franklin2]

There is also a ground wire that runs directly from the battery negative terminal, into the computer harness. Near the battery this ground wire has a disconnect. Since all this is near the battery it likes to corrode. I have tried it on mine before, if the engine is running and you pull this ground disconnect apart, the engine stops right now.

 

[rusty ol ranger]

Have you pulled codes?

It could possibly be ignition switch/key switch related too.

I had an 89 F250 that would die if you hit a big enough bump....after i changed the column it was fine

 

[Josh P]

If the ecm is original, it's old enough to have issues. I'd suggest after verifying the wiring is ok, if not resolved to get a spare ecm from a junk yard. 86-87 with the same trans will interchange.