2006 A4 2.0T M6 with just under 80,000.

Was driving on interstate last night going home from work, pulled off at exit to get gas and engine idled strange. Would act great, then bounce to 2,000...then back down to normal range and stutter but never die, then bounce back to 2,000 and repeated this. At high speeds, nothing unusual in performance, only at idle. No CEL. Continued home and parked out front to let engine idle in neutral while I listened to engine. After several minutes of idling, finally produced a CEL. Went to parts supply store and they pulled a total of 13 codes. P0507, with the remaining 12 being cylinder misfires.

I have a gut feeling it isn't a sensor..if a sensor was bad, I would assume that the CEL would be immediate. Thinking this is perhaps something needing cleaning...throttle body stuck...hose leak. Am I on the right track? Anything common to these cars when the P0507 code is given? I noticed a couple other threads on this, but no final results were given.

Thanks guys
m

 

Hi,

I am currently having this EXACT problem with my 2006 A4 2.0. What did the problem turn out to be? Im afraid its going to be expensive.

Thanks.

 

It is vacuum related. Start by checking PCV and lines. Could also be the cap on the intake manifold popped off (as was the case with mine) but either way, you're losing vacuum on the top end. If it is indeed the PCV valve itself, check with your dealer because it can be replaced free of charge as it is a recall item.

 

Throttle Valve Control Module, Checking ¤

Use only gold-plated terminals when servicing terminals in harness connector of Mass Air Flow (MAF) Sensor (J338).

Special tools, testers and auxiliary items required ¤

Multimeter.
Wiring diagram.
Test requirements
The Engine Control Module (ECM) ( J623) fuses OK.
Battery voltage at least 12.5 volts.
All electrical consumers such as, lights and rear window defroster, switched off.
Vehicles with automatic transmission, shift selector lever into position " P" or "N".
A/C switched off.
Ground (GND) connections between engine/transmission/chassis OK.
Throttle valve must not be damaged or dirty.
Coolant Temperature at least 80°C.

Function

Throttle valve operation occurs by an electric motor (Throttle Drive (for Electronic Power Control (EPC)) (G186)) in the Throttle Valve Control Module ( J338). It is operated by the Engine Control Module (ECM) (J623) and the Throttle Position (TP) Sensor (G79)/ Accelerator Pedal Position Sensor 2 (G185).

The Throttle Valve Control Module (J338) is made up of the following components:

Throttle Drive (for Electronic Power Control (EPC)) (G186)¤

Throttle Drive Angle Sensor 1 (for Electronic Power Control (EPC)) (G187)¤

Throttle Drive Angle Sensor 2 (for Electronic Power Control (EPC)) (G188)

The Throttle Valve Control Module (J338) cannot be serviced separately and must be serviced as a unit.

Test procedure


•Perform a preliminary check to verify the customers complaint. Refer to => [ General Diagnosis ] See: Initial Inspection and Diagnostic Overview\General Diagnosis.

Start diagnosis


•Connect the scan tool.
•Switch ignition on.
•Using the scan tool, check the throttle valve position (absolute) at idle stop:
•Slowly depress the accelerator pedal to Wide Open Throttle (WOT) stop while observing the percentage display. The percentage display must increase uniformly.
•Using the scan tool, check the throttle valve position (absolute) at Wide Open Throttle (WOT) stop:
•End diagnosis and switch ignition off.

If the specified values are not obtained:

•Remove engine cover - arrows -.
•Remove the Throttle Valve Control Module (J338 ) far enough so that the electrical connector terminals are reached.
•Disconnect the Throttle Valve Control Module ( J338) electrical harness connector - 2 -.


Checking resistance


•Using a multimeter, check the Throttle Drive (for Electronic Power Control (EPC)) (G186) at Throttle Valve Control Module (J338) terminals 3 to 5 for resistance.


Specified value: 1.0 to 5.0 ohms (at 20°C)

If the specification was not obtained:

•Replace the Throttle Valve Control Module ( J338 ). Refer to Fuel Injection and Ignition Repair Information.

If the specification was obtained:

Checking wiring

If the manufacturers test box is being used. Perform the following step.


•Install the test box. Refer to Fuel Injection and Ignition Repair Information

If the manufacturers test box is not being used. Perform the following step.


•Remove the Engine Control Module (ECM) (J623). Refer to => [ Engine Control Module, Replacing ] See: Engine Control Module\Service and Repair.
•Using a Multimeter, check the Throttle Drive (for Electronic Power Control (EPC)) (G186) at Throttle Valve Control Module (J338) electrical harness connector terminals to the Engine Control Module (ECM) ( J623) electrical harness connector T60 terminals for resistance.


Specified value: 1.5 ohms max.

If the specification is not obtained:


•Check the wiring for an open circuit, a short circuit to each other, Battery (+), and Ground (GND).
•Check the electrical harness connector for damage, corrosion, loose or broken terminals.
•If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring and if the voltage supply was OK:


•Replace the Throttle Valve Control Module ( J338 ). Refer to Fuel Injection and Ignition Repair Information.
•Erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] See: Scan Tool Testing and Procedures\Diagnostic Modes\Diagnostic Mode 04 - Erase DTC Memory.
•Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to => [ Readiness Code ] See: Monitors, Trips, Drive Cycles and Readiness Codes.


•End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was not OK:


•Replace the Engine Control Module (ECM) (J623 ). Refer to => [ Engine Control Module, Replacing ] See: Engine Control Module\Service and Repair.
•Assembly is performed in the reverse of the removal.

Final procedures

After the repair work, the following work steps must be performed in the following sequence:1.

Check the DTC memory. => [ Diagnostic Mode 03 - Read DTC Memory ] See: Scan Tool Testing and Procedures\Diagnostic Modes\Diagnostic Mode 03 - Read DTC Memory.2.

If necessary, erase the DTC memory. => [ Diagnostic Mode 04 - Erase DTC Memory ] See: Scan Tool Testing and Procedures\Diagnostic Modes\Diagnostic Mode 04 - Erase DTC Memory. 3.

If the DTC memory was erased, generate readiness code. => [ Readiness Code ] See: Monitors, Trips, Drive Cycles and Readiness Codes.


End of diagnosis