Always idles low,and stalls out often?

2004 FORD TAURUS

194,000 MILES • 3.0L • V6 • 2WD • AUTOMATIC

CATMAN2024

MEMBER
7 POSTS

My car listed above starts rather hard, has a new battery and starter. When it starts I have to hold down the gas pedal to keep it from stalling. When it is warm its fine but after it starts and I try to go it will stall out unless I get on the gas and hold the brake untill trafic clears and then i give it the gas and it accelerates just fine. It will stall out if i barely press the gas pedal. The stalling is driving me crazy. Has a new IAC ,6 new o2 sensors, new wires and plugs along with new fuel injectors and a few other small things. It has the original fuel pump, fuel pressure sensor and PCV valve, and has a new EGR valve too.

Oct 20, 2024 at 9:35 AM

JACOBANDNICKOLAS

✓Experienced Mechanic
110,240 POSTS

Hi,

This could be a few things. First, check for engine vacuum leaks. Here is a link that explains how to locate them:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If there are no leaks, I need you to get a live data scan tool and check what the engine coolant temperature sensor is signaling before you start it in the morning. The computer uses that information to determine the proper air fuel mixture. It should indicate very close to ambient temperatures. If it is off a good bit, that can cause the problem as well.

Let me know.

Joe

Oct 20, 2024 at 1:13 PM

CATMAN2024

MEMBER
7 POSTS

Hi Joe, I didn't find any vacuum leaks so I will have a coworker check the ambient temperature using his live data scan tool and I will let you know the outcome in the near future. Mark

Oct 29, 2024 at 12:37 PM

CATMAN2024

MEMBER
7 POSTS

Hi Joe, I didn't find any vacuum leaks so I will have a co worker check the ambient tempature using his live data scan tool and I will let you know the outcome in the near future, Mark

Oct 29, 2024 at 12:37 PM

JACOBANDNICKOLAS

✓Experienced Mechanic
110,240 POSTS

Mark,

Thanks for the update. Let me know what you find. Also, if the sensor checks good, then we need to check the idle air control system and maybe consider cleaning the throttle body. Actually, that would be a good idea regardless. Here is a link that explains how to do it:

https://www.2carpros.com/articles/throttle-actuator-service

Let me know.

Joe

Note: I realize you have already replaced the IAC. I may want to test it and confirm there are no obstructions where it mounts to the TB.

Oct 31, 2024 at 11:30 AM

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