Dies after starting

[Joel orozco]

I need help with my 86 ford ranger 2.9 it stalls for a while then after it starts it wont last no more then a second running after it dies any help on what could be wrong?

 

[RonD]

Welcome to TRS

Could be a few things

1986 2.9l uses a TFI module for spark, these were a known issue
If the engine starts and runs OK while its still cold and only has re-start issue after its warmed up then I would replace the TFI module on distributor
This can also be a Coil Issue, no start when warm, but less likely than the TFI module


If the no start can happen cold or warm then probably a fuel issue
1986 has 2 electric fuel pumps, one inside the gas tank and one on the drivers side frame rail
If either fails you will get what you describe, starts but dies quickly
(Clogged fuel filter will cause that as well)


You can do the 50/50 test, been around for 100+ years
On your 2.9l pull off the big air tube that runs from air cleaner box to the upper intake, pull it off of the intake, make sure fan can't hit it
Get some gasoline in a spray bottle or Quick Start(ether)
Have some one crank the engine while you spray fuel into the intake

If engine starts and stays running while you spray in fuel, but dies when you stop adding fuel, then spark is OK, but no fuel delivery
If engine doesn't start or fire then No Spark
50/50 instant results

 

[Joel orozco]

Welcome to TRS

Could be a few things

1986 2.9l uses a TFI module for spark, these were a known issue
If the engine starts and runs OK while its still cold and only has re-start issue after its warmed up then I would replace the TFI module on distributor
This can also be a Coil Issue, no start when warm, but less likely than the TFI module


If the no start can happen cold or warm then probably a fuel issue
1986 has 2 electric fuel pumps, one inside the gas tank and one on the drivers side frame rail
If either fails you will get what you describe, starts but dies quickly
(Clogged fuel filter will cause that as well)


You can do the 50/50 test, been around for 100+ years
On your 2.9l pull off the big air tube that runs from air cleaner box to the upper intake, pull it off of the intake, make sure fan can't hit it
Get some gasoline in a spray bottle or Quick Start(ether)
Have some one crank the engine while you spray fuel into the intake

If engine starts and stays running while you spray in fuel, but dies when you stop adding fuel, then spark is OK, but no fuel delivery
If engine doesn't start or fire then No Spark
50/50 instant results

I will try that tomorrow and i will update you thank you so much!!

 

[rusty ol ranger]

Will it stay running with your foot on the throttle?

If so you need an IAC

 

[Joel orozco]

Will it stay running with your foot on the throttle?

If so you need an IAC

No it still dies

 

[Joel orozco]

Update when i put gas in the carb it turns on but when i let go of the key it turns of

 

[RonD]

???

2.9l was fuel injected, no "carb"

 

[Joel orozco]

???

2.9l was fuel injected, no "carb"

Yeah on the throttle body my bad

 

[RonD]

So it fires when starter motor is on when you manually add gasoline, but stops firing when key is released, back in RUN(ON)

The older vehicles, pre-1990's, did have 2 circuits in the ignition switch, so Ballast Resistors(resistor wires) could be used on start up and running


Get a 12volt test light or volt meter
Coil has a green/yellow wire and a red/green wire
Green/yellow is the Ground
Red/green is the 12volt

With key on the red/green wire should have 12volts, well battery volts whatever the battery has
If not then that is at least one if the issues

You can turn the key to START and see if Coil now has 12volts while cranking
You can unhook the Red/blue wire on start relay(solenoid) on inner fender, this will prevent starter motor from running with key in START but won't effect the 12volt at coil for testing

On the upper intake next to throttle body is the IAC Valve, has 2 wire connector, one wire is red
With key on, test that red wire, it should have 12volts, if not then EEC Relay or its fusible link is bad
OR
Ignition switch is bad

I would think ignition switch if coil and IAC Valve both lack 12v with key on