Intermittent Random engine cut-offs

[helpme]

Seems to be a loss of 12V to the fuel pump. Replaced relays. 94 OBD1 Ranger 3.0. Thanks.

 

[rusty ol ranger]

Just to the fuel pump youre losing power?

 

[bhgl]

I had this happen recently when turning onto a road, applying some sudden throttle, and hitting a few bumps.

The engine bogged own and died and the dash displayed a Battery and ABS light, my truck does not have ABS, so I thought that was a bit strange.

 

[RonD]

All Rangers after 1986 or so have Rear Wheel ABS(RABS), some got 4 wheel ABS(4WABS) 1998 and up
ABS light should come on with key on and then go off

If you were under 1/8 tank of gas then when turning 90deg left or right the gas in the tank can slosh to one side and fuel pump sucks in some air, then hard acceleration can cause engine to stumble and even die

But ABS light shouldn't have come on just battery light(normal when engine stalls)
ABS light coming on usually means whole vehicle lost 12volts momentarily, not just the fuel pump, and ABS light should have gone off after a few seconds

In 1994 there will be the Starter Relay on the inner fender, sometimes mispronounced as "starter solenoid", lol

One of its larger posts will have battery Positive wire attached and several other wires with it on that one post
That post is the 12volt Power distribution point for the whole vehicle

Remove the Battery Negative cable from the battery, FIRST

Then remove all the wires from the larger starter relay post and clean them, then put them back on
Clean Negative battery cable and terminal then put it back on

See if the problem repeats, this would be "bump" related not turning like a low fuel level issue

Could be an issue in the engine bay fuse box, but that gets all its 12volt power from that starter relay post so start there

 

[helpme]

You da man, RonD. Thanks.

 

[bhgl]

All Rangers after 1986 or so have Rear Wheel ABS(RABS), some got 4 wheel ABS(4WABS) 1998 and up
ABS light should come on with key on and then go off

If you were under 1/8 tank of gas then when turning 90deg left or right the gas in the tank can slosh to one side and fuel pump sucks in some air, then hard acceleration can cause engine to stumble and even die

But ABS light shouldn't have come on just battery light(normal when engine stalls)
ABS light coming on usually means whole vehicle lost 12volts momentarily, not just the fuel pump, and ABS light should have gone off after a few seconds

In 1994 there will be the Starter Relay on the inner fender, sometimes mispronounced as "starter solenoid", lol

One of its larger posts will have battery Positive wire attached and several other wires with it on that one post
That post is the 12volt Power distribution point for the whole vehicle

Remove the Battery Negative cable from the battery, FIRST

Then remove all the wires from the larger starter relay post and clean them, then put them back on
Clean Negative battery cable and terminal then put it back on

See if the problem repeats, this would be "bump" related not turning like a low fuel level issue

Could be an issue in the engine bay fuse box, but that gets all its 12volt power from that starter relay post so start there

I recently used Forscan to program a key, and while I was there I checked which modules were found and ABS was not found, other modules that weren't working displayed an error, but the ABS section just said none.

ABS light does come on on startup however, so maybe it's not working properly? I'll have to take the truck out and try to lock up the wheels to test it.

I assumed it was an issue with the car momentarily losing power from the battery, I'll double check my terminals and the starter relay as you mentioned

 

[RonD]

With engine running the vehicle is not using the battery at all
Alternator supplies all the voltage, minimum 13.5volts, usually about 14volts
Battery is only 13.0volts at most, so with engine running voltage flows TO the battery to keep it charged
A vehicle will stay running with battery disconnected

So loose battery cables wouldn't cause a stall, a no start yes, but not a stall

Alternators 13.5v+ volts is hooked to the post on the starter relay and goes to the engine fuse box from there

 

[bhgl]

With engine running the vehicle is not using the battery at all
Alternator supplies all the voltage, minimum 13.5volts, usually about 14volts
Battery is only 13.0volts at most, so with engine running voltage flows TO the battery to keep it charged
A vehicle will stay running with battery disconnected

So loose battery cables wouldn't cause a stall, a no start yes, but not a stall

Alternators 13.5v+ volts is hooked to the post on the starter relay and goes to the engine fuse box from there

So, while I was digging into the airbag system last night I finally got around to popping the hood in order to disconnect the battery.

Sure enough, the positive terminal was basically barely on. That plus some corrosion probably explains why I got that stall following a bump, I'll need to drive the car in similar conditions to see if it is in fact a totally separate issue.


Given your post above, it may also mean I have a dying alternator that isn't providing enough charge to keep the engine running on its own... Shit.