Help Please! Idle / Dieing Issues

[BamaB2]

Help Please! Idle / Dieing Issues -FIXED!

My vehicle: 2001 Explorer Sport 4.0 2wd

It starts and idles fine. Usually idles around 900-1000 when first started and drops to 600-700 after a minute or two. After driving for a short time, the idle stays around 600 when stopped and in drive. When I shift to neutral or park, or sometimes shifting between drive and reverse, the motor dies. It will restart, but dies. Let it sit for a minute or two and it will restart and idle around 600 again.

There are no issues while driving or stopped and in drive.

May be a seperate issue, but when the AC is on, it sounds like the compressor cycles on and off very 5-10 seconds. The idle goes up and down each on / off cycle, in park and when stopped and in drive.

I've tried cleaning the MAF with contact cleaner. No change.

Thanks

 

[Tyson128]

Check your oil cap for the presence of a milky white substance . Possiblr anti freeze in the oil?

 

[BamaB2]

Bumping back to the top. I checked the oil. No sign of water. Have driven it a lot, including a 700 mile round trip. Good milage (21-23 mpg). Idle is fine while running and stopped in drive, like at a red light. Idle is fine in park. No issues except it will die, most of the time, when shifting from drive to reverse or park. Could it be the IAC? Did the voltage and ohm check. All was good except the ohm check between the terminal and the IAC body. It was 0.

Also, when the AC is on at idle, it sounds like the compressor cycles on and off every 10-15 seconds. Idle goes up and down.

Thanks

 

[1AJeremyD]

A/C cycling is normal. When the idle goes up thats when the compressor is on. When it shuts off thats when the clutch disengages and the idle should drop.

Try cleaning the IAC. Are there any CEL?

 

[BamaB2]

Jeremy,

No CEL. Note that the compressor is cycling on and off every 10-15 seconds (maybe quicker) when idling. Seems to do fine at speed.

All the other stuff happens whether the AC is on or not, just to be clear. It runs great other than when I stop and shift to reverse or park. Thanks

 

[2000StreetRod]

A/C cycling

The PCM knows when the A/C compressor clutch is engaged and increases the commanded idle speed to the IAC valve. When the clutch disengages the PCM reduces the idle speed. If your compressor is cycling that rapidly the system is either low on refrigerant or the pressure switch is defective.

I suggest that you clean the IAC valve and check your refrigerant pressure.

 

[1AJeremyD]

I am not sure about our explorers but in the past, I have seen clutches engage and disengage at a rapid rate on vehicles such as chevy s-10s and other vehicles like that and have operated fine. Is the temperature coming out not cold enough? I also agree that a rapid cycling clutch can mean low coolant and the PCM is trying to compensate.

 

[SkyJumper]

The quick cycling is from low freon pressure and as it gets lower it will then continually run the compressor. The IAC will cause stumbling and stall at normal temp readings, not at cold readings. I would see what a new IAC would do for ya. But I would also have a pressure check done on the air conditioning system for a possible slow leak, low pressure only come from a leak.

 

[BamaB2]

Thanks guys. I'll try those suggestions and post the results.

 

[BamaB2]

Fixed! Removed and cleaned the IAC with carb cleaner and that did the trick. Driven for several days to make sure. The rpm has occasionally dipped down to 200-300 when shifting to park but pops back up hasn't died . A/C operation is back to normal. May still have to replace the IAC eventually but at least I know the $100+ is going in the right direction. Thanks for the help.

 

[Tyson128]

Dieing Issues

Great news! Now you know