Friends 1997 2.3 Ranger starts/dies after a few minutes

[Mazda]

Hello All,

Trying to help a friend at work get his Ranger running. Here is the story.

A few weeks ago truck starts fine buy starts to get a stumble before he ever gets out of the aprt complex. I come over scan it shows code for IAC and TPS. Replace IAC and it runs great. We take it on a 15-20 mile drive never stumbles or dies like it was doing before.

Next morning tries to drive to work makes it to the road and it starts to die at the stop sign, Dies, Restarts and he goes back home. I come over rescan with NO CODES and it starts right up, we take it again on a longer driver 30 miles. Again no stumble or engine shutoff. Now i'm really puzzled.


Next day we get a fuel pressure gauge. Fuel pressure is at 30 with engine running but it will die after a few minutes running. Pressure was at 30 psi and did not loose any pressure when key was off. He wanted to replace Fuel Pressure Regulator so we did with no change. Starts up RPM go to 1200 then back to 800 or so, dies a few minutes later.

So is fuel pump going. I have only dealt with either the pump comes ON or it doesn't. Also switched fuel pump relay with another to rule that out.

Thanks for any help you can give.

Bryan

1997 Ranger 2.3 Lima Auto 177,256 miles

 

[tomw]

When it dies, find the fuel rail schraeder valve, and check for pressure. It should have residual pressure if the pump has been working. It will not leak down instantly, unless the injectors have been trying to spritz as you crank. So, don't crank!, check the pressure immediatly after it stalls.
Get a spare plug, and carry it in the truck. When it dies, pull a plug wire, or coil, depending, and crank, stuffing the spare plug into the wire. Check for spark.
If everything goes dead, gauges, etc, then check the ignition switch for being worn or coming apart. It can lose conductivity if the parts wiggle apart as the plastic ages, and power to all will be lost.
Check battery cables for corrosion, grounds for tightness & corrosion. Ground wire to the cab, bare, from back of cylinder head to the firewall, too.
tom

 

[Mazda]

Thanks tomw,

Yes he did have a problem with the battery before this all started. Had to put a new negative terminal on the wire. I'm thinking he pulled a ground out or something maybe. Power is not lost in the cluster or the lights so that probably rules out the ignition switch.

I'll have to go back over and check to make sure there is still fuel in the rail after it dies. If there is then that rules out bad fuel pump?.

 

[WarHawk-AVG]

Was it ever wrecked...does it die when stopping

Have you checked the inertia switch on the passenger side...could be faulty

Have you changed fuel filter?

 

[danielwd]

Your scenario reminds me of when my fuel pump bit the dust...it did so slowly. In retrospect, I could tell over the course of a couple of weeks something was wrong because the engine was seemingly put-put-ing when it did not do so before.

So the idea that a fuel pump is either alive or dead was not proved correct by my situation where the truck would literally run then die, then would do nothing (not even crank). Then the next morning it would start perfectly fine.

Obviously, when it is dead, check to see if you hear the hum from behind the passenger side when turning the key. If you hear nothing, then it is dead. Even if it starts up the next morning...it is probably going to die for good soon.

Check the inertia switch too.

 

[tomw]

A 'current draw' test on a fuel pump will give an indication of its 'state of life', as a pump nearing its end will draw more juice. FWIW.
When it dies, I would cycle the ignition from OFF to ON, and listen for the short pump 'prime' cycle. If I heard that, I'd have more confidence the pump was working.
If it has pressure, and still dies, I'd be checking the fusible links on the starter relay or the power distribution box for loose, corroded, or damaged fittings.
If things randomly flicker, flash, or turn off and on, the power box and grounds and ignition switch would be my areas of investigation.
tom