Hi Everyone!

I Have a VW Transporter (T4), 1996 model with 2.5TDI engine.

Using VCDS-lite I receive error messages I belive are connected to the Intake manifold temperatu sensor. The car has been in the garage for some days now (I've fixed some other erros like coolant sensor and a broken pipe for the diesel, new pipes for the brake fluid etc.) Before I placed it in the garage the engine worked unstable when engine was cold, gave some extra smoke thru the exhaust and things like this.

I had some error codes like for the coolant sensor and the error for the intake manifold temp sensor - error code 00527 (G72).


Today I replaced the Intake manifold sensor with a new one. I used multimeter at the connection and also tested the resistance in the old sensor. The Voltage in the connection was close up to 13.8 Volt and if I remember correctly the old sensor had around 6000OHM (6kOMH).

After I replaced the sensor VCDS-lite reports the following error codes:
"
Sunday, 09 September 2012, 17:54:32.
VCDS-Lite Version: Release 1.1
Control Module Part Number: 074 906 021 F
Component and/or Version: 2,5l R5 EDC SG D1H
Software Coding: 00000
Work Shop Code: WSC 00000
VCID: 13593C4F727B
2 Faults Found:
00527 - Intake Manifold Temperature Sensor (G72)
29-00 - Short to Ground
00000 - Shareware Version. To Decode all DTCs
00-00 - Please Register/Activate
---------------------------------------------------------------------------
"

I cleared th codes and VCDS-lite reported then the 65535 code (Thats not good??):


"
Sunday, 09 September 2012, 17:54:45.
VCDS-Lite Version: Release 1.1
Control Module Part Number: 074 906 021 F
Component and/or Version: 2,5l R5 EDC SG D1H
Software Coding: 00000
Work Shop Code: WSC 00000
VCID: 13593C4F727B
2 Faults Found:
65535 - Internal Control Module Memory Error
08-10 - Control Limit Surpassed - Intermittent
00000 - Shareware Version. To Decode all DTCs
00-00 - Please Register/Activate
---------------------------------------------------------------------------
"

I don't like codes that says something about Internal Control Module Memory Errors. That is dangerous for me!!.


Finally I disconnect the Intake manifold sensor. Then the VCDS-lite reports only the 00527 error (G72), like this:

"
Sunday, 09 September 2012, 17:56:08.
VCDS-Lite Version: Release 1.1
Control Module Part Number: 074 906 021 F
Component and/or Version: 2,5l R5 EDC SG D1H
Software Coding: 00000
Work Shop Code: WSC 00000
VCID: 13593C4F727B
1 Fault Found:
00527 - Intake Manifold Temperature Sensor (G72)
29-00 - Short to Ground
---------------------------------------------------------------------------
"


At my car the Intake sensor have two pins and there are also a vacuum pipe from the Intercooler close to the Intake sensor. This vacuum pipe are connected into the ECU in the other end. (Sorry for bad English and grammar).

I've also tried to replace the vacuum pipe with a new one to make sure that there is no problem with the pipe. Replacing did not help and I continued to get the 65535 error message.

Before I left the car into the garage I think it was not so good, and had loss of power. This might be better since one of the diesel return pipe was broken, but I also think this G72 sensor and maybe the ECU still is a problem and that the car will go for the emergency modus.

I also know that inside the ECU is the sensor that messaure the airflo from the intercooler.


SO OVER TO THE QUESTIONS:
1. Is my ECU broken? I think it is strange, but...
2. Can there be problem with the wiring? I can messaure the 12 volt in the pins to the intake sensor, but the problem might be somewhere else?
3. Is 13. volt okay into the sensor?

I guess there are many things that I dont know about this engine and system so if somebody knows how to search for errors or have any ideas of what the real problem might be I would like to hear about it :-)