Park

[Johnny Creeps]

My 94 Ranger 4.0L 4x4 runs like a beast... until I put it in Park... it dies, then when trying to restart it, it acts like it's flooded...when it finally starts, it chugs like a train and spits black smoke. Before you say that it's the fuel pressure regulator, it's not. Something to do with throwing it in Park that's starting the whole cluster ****. Any ideas?

 

[Spott]

My 94 Ranger 4.0L 4x4 runs like a beast... until I put it in Park... it dies, then when trying to restart it, it acts like it's flooded...when it finally starts, it chugs like a train and spits black smoke. Before you say that it's the fuel pressure regulator, it's not. Something to do with throwing it in Park that's starting the whole cluster ****. Any ideas?

Do you have any engine codes?

 

[RonD]

What happens when you put it in Neutral, computer gets same signal, from NSS(neutral safety switch), in Park and Neutral?

The signal tells computer to bump up the idle, open IAC Valve more, when In Gear, so when in Park or Neutral the computer would close IAC valve a bit for lower idle.
If IAC valve closed all the way engine might stall but wouldn't flood.

Same thing happens if you have AC and turn it on, that also sends signal to computer to bump up idle.

Even though you know it isn't the FPR, check it's vacuum line for fuel or fuel smell, it is FREE to do, and takes it right off the table.

Only other thing I can think of would be wiring issue, and only because of your description of "throwing it into Park".
If you put it into Park "normally" does it still stall?

 

[Johnny Creeps]

It only does it in park... not in neutral.
The reason I say it's not the FPR is because that was my first logical guess so I replaced it... still no good.
I've been shutting the truck off in drive and then putting it in park to avoid the flooding issue. I can start it in park just fine, it's just when I throw it in park from drive or reverse.

What happens when you put it in Neutral, computer gets same signal, from NSS(neutral safety switch), in Park and Neutral?

The signal tells computer to bump up the idle, open IAC Valve more, when In Gear, so when in Park or Neutral the computer would close IAC valve a bit for lower idle.
If IAC valve closed all the way engine might stall but wouldn't flood.

Same thing happens if you have AC and turn it on, that also sends signal to computer to bump up idle.

Even though you know it isn't the FPR, check it's vacuum line for fuel or fuel smell, it is FREE to do, and takes it right off the table.

Only other thing I can think of would be wiring issue, and only because of your description of "throwing it into Park".
If you put it into Park "normally" does it still stall?

 

[Andy D]

My total guess is that shifting into Park grounds something in the column.

 

[Johnny Creeps]

Nothing happens when I put it in neutral... only when I put it in park.

What happens when you put it in Neutral, computer gets same signal, from NSS(neutral safety switch), in Park and Neutral?

The signal tells computer to bump up the idle, open IAC Valve more, when In Gear, so when in Park or Neutral the computer would close IAC valve a bit for lower idle.
If IAC valve closed all the way engine might stall but wouldn't flood.

Same thing happens if you have AC and turn it on, that also sends signal to computer to bump up idle.

Even though you know it isn't the FPR, check it's vacuum line for fuel or fuel smell, it is FREE to do, and takes it right off the table.

Only other thing I can think of would be wiring issue, and only because of your description of "throwing it into Park".
If you put it into Park "normally" does it still stall?

 

[Ranger4x4.0]

I would think it has to do with the iac and park. When you put it in park, the computer tells the iac to be dumb? My guess.

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