2009 Envoy - Replaced tb, did idle relearn...still have P0507

[midnightbluS10]

Just replaced the tb on my 09 Envoy. Did the 3/1/3 minute idle learn thing and it didn't help. Still have P0507 and idle isn't right. It sticks at 1200+ rpm if I gas it. If I drive, it'll accelerate continually without touching anything. So it's obviously not right.

Tb is a *NEW* Bosch unit from Rock Auto. New, updated gasket from Victor Reinz. The hose under the plastic box is hooked up on both ends and so is the hose on the throttle body itself. I also unhooked POS & NEG on thr battery, touched the cables together for 60 seconds, and let the truck sit for an hour with battery unhooked and that didn't help, either.

I'm thinking it's a bad tb out of the box. Anyone got any suggestions? Am I missing something? Did I do the wrong idle relearn?

Thanks!

 

[mrrsm]

Paul "Scanner" Danner's Video Linked Below describes a method for viewing the Engine Performance parameters of a GM Vehicle throwing a P0507 Code that he tracks down as being caused by a MASSIVE Vacuum Leak coming from a Failed Brake Booster.

He obtains Diagnostic Confirmation by using a Smoke Machine (with a Check-Valve Bypass Tool inserted into the body of the Brake Booster Chamber). However... Paul also shows that the Alternative Diagnostic Test Method is to merely Pinch Off the Brake Booster Hose with the Engine on "High Idle" and see if the Engine RPM declines or stalls the Motor.

All of these matters are being discussed in front of the Students at the Rosedale Yechnical Institure and even though this vehicle is NOT one of the GMT360s... the GM 2000 Vehicle involved here is focused on the MAP Sensor... it will be helpful to follow his logic on what to look for after he Starts the Engine and Steps on the Brake to witness the Engine Stalling.

In your case, you would want to look at the MAF Sensor Readings along with the TPS (TAC) Throttle Plate Angle and the Two APP Inputs to ensure the PCM is not getting any *specious data* about those inputs.

The MAF-IAT needs to be correctly "Weighing" the amount of AIR at a variable Temperature as it is being ingested through the Intake System ahead of the Throttle Body, so you'll want to be suspicious and look for any Disconnected Harness Connectors or Loose-Leaking Vacuum Hoses ALL OVER THE ENGINE.

Focus on finding the source of any MASSIVE amount of Un-Metered, Un-Regulated AIR somehow getting into the Engine and skewing the PCM response to want to Dump In More Fuel to establish a Stoichiometric AIR/FUEL Balance resulting in the Increase in the Engine RPM:

Hope This Helps...