Hi,

All of a sudden, today, when I started my truck after sitting about 36 hours, it ran very low idle ( 500 RPM), and died. I started it again ( started right away) and held the accelerator down at about 1000-1200 RPM for a few minutes. Engine purred at this RPM and sounded normal. When I let off the gas, the low idle returned, but did not die. After 15 minutes of driving, idle was normal at 800 RPM.

Spark plugs, distributor, cap, rotor, wires, fuel filter replaced last year. Recent vacuum hose repair. Recently replaced battery.

Where do I start looking???

Thanks Laura

p.s. I can't ask my husband cause he will start yelling at me to get rid of the truck!

 

Ford Fuel Injection » Engine Coolant Temperature Sensor (ECT) Here is a link on how to test the Engine Coolant Temperature sensor. I think that is where I would start.

 

Today it started nearly normal, after one quick fall off in rpm, I pressed the accelerator for a moment, and then it returned to normal at about 1000 rpm for a minute or so, then fell off to 800 rpm. Sounds normal....

Could that sensor be intermittent?

laura

 

Unlikely to be intermittent.
Maybe see if it does it again and then maybe see if there are any trouble codes stored.

 

Now I notice, when in park, the idle fluctuates slightly. I got an oil change today and the tech tried to read the codes, but he has to set up his computer different to do so. He asked if I could come back in the morning ( they were lined up for oil changes) and I said I would. He also suspects a sensor ( IAC or TPS).

I did recently have some of my vacuum hoses replaced due to leaks.

Thanks

Laura

 

Yes, get it checked for trouble codes. IAC valve and TPS could be possible.
Good luck.