Low Idle P0113 Error

[rifleman625]

99 5.4, just had the throttle body cleaned and a dfpe sensor due to the P01401 error code. I just got the vehicle back last night. It now has what I believe low idle, around 500. The CEL is not on. But it shows a P0113 error. I replaced the IAT sensor due to that error. It didnt help at all. If you put it in gear and give it a little throttle the headlights dim and it wants to stall. This morning I started it up. It dies when you try to put it in gear. Any suggestions on where to start? I was wondering if this was symptoms of a dirty IAC. I looked for any disconnected hoses and couldn't find anything.

 

[docraymund]

Measure the resistance between the 2 pins on the idle air control motor. It should be 7 to 13 ohms.

 

[1955moose]

You may have a battery/ alternator problem. One bad cell on these SUVs can cause all kinds of problems. Load test battery, and have charging/starting system checked.


Sent from my iPhone using Tapatalk

 

[rifleman625]

So after driving it around for a while. It does it really bad when it's cold. After it's warmed up not as bad. Also I had it scanned at Autozone even though there is no CEL. It threw a P0402. I'll start reading into that but any tips would be appreciated. Did something go wrong with the TB cleaning?

 

[Bedrck47]

Check the connector for the dfpe sensor for corrosion and that it is completely plugged in.
Also check the hoses that connect to the dfpe sensor

 

[Bedrck47]

Symptoms
You may notice drivability problems such as the engine may surge off idle. There may also be other symptoms.

Causes
A code P0402 most likely means one or more of the following has happened:

• The DPFE (differential pressure) sensor is faulty and needs to be replaced
• There is a blockage in the EGR (most likely carbon buildup)
• The EGR valve is faulty
• The EGR valve may not be opening due to a lack of vaccuum

Possible Solutions
With a P0402, it is common for people to replace the EGR valve, only to have the problem return. The most likely solution is to replace the DPFE sensor.

• Check the voltage at the DPFE sensor both at idle and when the EGR is open
• Replace the DPFE sensor

Related EGR codes: P0400, P0401, P0403, P0404, P0405, P0406, P0407, P0408, P0409