Idle air control valve from throttle body

2004 CHEVROLET SILVERADO
180,000 MILES • 5.3L • V6 • 2WD • AUTOMATIC
Avatar
MARTIN GARCIA
  • MEMBER
  • 5 POSTS
The throttle body has two different connectors one form TP sensor and IAC valve

The harness came with the engine but the harness has one connector that is an 8 pin for the electronic throttle body and mine has the IAC (4 pin) and the TP sensor (3 pins)....engine is always stalling because I need to keep the foot on the gas pedal. not unless either i adjust the throttle valve to keep open just enough for my engine not to stall or fix my IAC valve connect problem. how do I solve this?!
May 1, 2020 at 8:29 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

Did you replace the engine? Are you able to remove the TPS and IAC from the old motor and switch them with the new one?

I'm not going to lie. I'm not sure exactly what has been done. If you changed the engine, was it from a different model year?

Let me know.
Joe
May 1, 2020 at 9:17 PM
Avatar
MARTIN GARCIA
  • MEMBER
  • 5 POSTS
There was an engine swap from the previous owner but I bought it like this, so I'm stuck with this. first picture is the throttle body it has and second picture is the throttle body connector that my harness came with. the TP sensor is was already connected but where do I wire the IAC valve? can I connect using this wiring diagram? I hope you understand what I'm trying to figure for the past week.
Images (Click to enlarge)
Attached Media
Attached Media
Attached Media
Attached Media
May 1, 2020 at 9:27 PM
Advertisement
Avatar
MARTIN GARCIA
  • MEMBER
  • 5 POSTS
So the IAC has 4 pins do I connect from somewhere else of the harness?
May 1, 2020 at 9:43 PM
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

I attached a pic below that shows an 8 pin connector. See if that is what you are looking at. Also, if you want, I can attach all wiring schematics for power-train management. I'm not gong to lie. I need to see what is going on with this one. If you want the schematics, they indicate wire colors and where they travel. Since we are dealing with two different designs, I don't want to give you bad info.

Let me know if the schematics will help.
Joe
Image (Click to enlarge)
Attached Media
May 1, 2020 at 10:05 PM
Avatar
MARTIN GARCIA
  • MEMBER
  • 5 POSTS
Yes, the schematics you sent me is what I have in the harness and on the second picture is what I have for the IAC on the throttle body.
Images (Click to enlarge)
Attached Media
Attached Media
May 1, 2020 at 10:43 PM
Avatar
MARTIN GARCIA
  • MEMBER
  • 5 POSTS
How do identify the highs and lows for the IAC?

Would these be my wires I need?

Black/white, light blue/black. , black , gray
Ref low. , 5v. , ref low, 5v
May 1, 2020 at 10:48 PM
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
I have to be honest, I'm questioning it. However, I believe what you are saying is correct, but the purple wire is tp sensor 2. I would thing that is the third wire for idle speed. The Black / Gray you mentioned if going to the cruise control, which I don't believe is needed for idle speed.

Let me know.
Joe
Image (Click to enlarge)
Attached Media
May 2, 2020 at 8:05 PM