1993 2.3 Cold Idle Issue

[munnson]

First off thank you for any help in advance that anyone can provide. I have a 1993 Ranger XLT with the 2.3. Truck starts great and will idle then eventually stall/die. If I try to rev it up while it is warming up it misses and backfires/pops near the intake. It will continue to do this until it reaches operating temp. Once operating temp is reached it runs great and the problem does not return until the next cold start and warm up cycle. Truck has 150k miles and auto trans.

 

[RonD]

Welcome to TRS

I would change the ECT(engine coolant temp) sensor just on speculation since it is not too expensive

There are TWO temp devices on fuel injected engines
One is the 12volt sender that is used only for the dash board temp gauge, often a 1 wire unit

The other is the ECT SENSOR always 2 wires, uses 5volts, it tells the computer when to Choke the engine so it can run cold, engine needs a rich fuel mix, high idle and advanced spark when cold or it will stall out
Then as engine warms up computer leans out the mix for warm running

This sounds like whats happening on yours, no Choke, might not be the issue but reads like it is.

You can test ECT sensor with OHM meter and boiling water, but have to remove it, and at that point..............well its just easier to replace it

 

[munnson]

Thank you. From some of my research this definitely sounds like a likely candidate and cheap enough to try. Any idea where it is located on this old 2.3?

 

[RonD]

The SENDER is on drivers side rear by oil pressure sender, just FYI, not the one you want

The ECT sensor should be on the front of the engine, up high, maybe on a coolant line

 

[munnson]

The SENDER is on drivers side rear by oil pressure sender, just FYI, not the one you want

The ECT sensor should be on the front of the engine, up high, maybe on a coolant line

Thank you. I went out this morning. Unplugged the sensor and noticed the pins were corroded on the sensor. Cleaned them, plugged it back in and fired it up. Ran perfect. The corrosion must've been causing an issue reading the sensor.

 

[RonD]

Good work

Thanks for the follow up and hopefully the FIX