1994 ford ranger 2.3l

[jones5818]

i have a 1994 ford ranger recently changed coolant temp sensor and mass air flow sensor.when you shift into second gear motor shuts off like you turned the key off anyone know what it might be.manual trans

 

[RonD]

Welcome to TRS

I assume if you let it warm up and REV engine it doesn't shut off?

It only shuts off when moving

Once engine is running only reason it would shut off would be no spark or no fuel
MAF or ECT sensors wouldn't have anything to do with that

Shifting to 2nd gear wouldn't either

i.e. what if you skip 2nd and go directly to 3rd from 1st, does it still shut off?
There is only a Reverse light switch in a manual transmission, and it wouldn't cause a stall, manual trans has no other electrics

But what about the electrics?
When the engine stalls what happens to the gauges?
does the oil light or Battery light come on?
Or does the dash go dead, like key was shut off?

What about re-start?
Does it start right back up after the stall or do you have to wait before it will start again?

 

[jones5818]

Welcome to TRS

I assume if you let it warm up and REV engine it doesn't shut off?

It only shuts off when moving

Once engine is running only reason it would shut off would be no spark or no fuel
MAF or ECT sensors wouldn't have anything to do with that

Shifting to 2nd gear wouldn't either

i.e. what if you skip 2nd and go directly to 3rd from 1st, does it still shut off?
There is only a Reverse light switch in a manual transmission, and it wouldn't cause a stall, manual trans has no other electrics

But what about the electrics?
When the engine stalls what happens to the gauges?
does the oil light or Battery light come on?
Or does the dash go dead, like key was shut off?

What about re-start?
Does it start right back up after the stall or do you have to wait before it will start again?

yes dash lights come on starts right back up.didnt try skipping gears was frustrated having to change other sensors that went bad.someone suggested it might be the computer

 

[RonD]

Computers rarely fail, but are often replaced, lol

90% of sensors or engine electrics replaced were working just fine, just FYI

Most engine problems are the same as they always were, fuel or spark problem, the electronics just makes them more reliable, so we don't have to work on them all the time.

That being said, since it is an instant cut off, not like "running out of gas" I would suspect spark system.
You should have dual coils so a bad coil is out
The 1994 2.3l was the last year of the ICM(ignition control module), and it can be tested, it is on the front of the intake facing fan.
Most auto parts stores can test them.
And these were a known issue on this engine.

If CEL(check engine light) is working, comes on when you turn on the key then goes off after engine starts then computer is working fine, it runs a self test every time it is powered up.

You can also check computer codes by "flashing" the CEL and counting the flashes, not hard to do

Google: 1994 ford ranger diagnostic codes video

There are a few videos on how to do it
The codes in memory may point the way to a problem.

 

[jones5818]

Computers rarely fail, but are often replaced, lol

90% of sensors or engine electrics replaced were working just fine, just FYI

Most engine problems are the same as they always were, fuel or spark problem, the electronics just makes them more reliable, so we don't have to work on them all the time.

That being said, since it is an instant cut off, not like "running out of gas" I would suspect spark system.
You should have dual coils so a bad coil is out
The 1994 2.3l was the last year of the ICM(ignition control module), and it can be tested, it is on the front of the intake facing fan.
Most auto parts stores can test them.
And these were a known issue on this engine.

If CEL(check engine light) is working, comes on when you turn on the key then goes off after engine starts then computer is working fine, it runs a self test every time it is powered up.

You can also check computer codes by "flashing" the CEL and counting the flashes, not hard to do

Google: 1994 ford ranger diagnostic codes video

There are a few videos on how to do it
The codes in memory may point the way to a problem.

.i forgot to mention i changed the icm might be possible i got a defective one.i changed it because the truck wouldnt start then still wouldnt start unplugged the mass sensor truck started its weird then changed mass sensor runs good thats when this problem started thanks for your input.if you have more let me know thank you i did pull codes thats why i changed the coolant temp sensor had a code for that took are of that code