Hesitation!

[LHD_Kid]

Exqueeze me? Of course knock sensors throw codes:

•2141 (Blink Fault Code), 00535 VAG1551/2 Fault Code Number
Knock regulator #1
Excessive knock, timing is being retarded by maximum amount,
Symptom: Low boost on 20V, Fuel octane too low, Excessive Compression, excessive boost

•2142 (Blink Fault Code), 00524 VAG1551/2 Fault Code Number
Knock sensor #1 (G61)
Open or short circuit, Defective sensor Check sensor and wiring
Symptom: Timing retarded, High fuel consumption, power loss, Boost pressure not attained

•2143 (Blink Fault Code),00536 VAG1551/2 Fault Code Number
Knock sensor #2, (Cylinders 3, 4, 5)
Excessive knock, timing is being retarded by maximum amount.
Symptom: Fuel octane too low, Excessive Compression, excessive boost

•2144 (Blink Fault Code), 00540 VAG1551/2 Fault Code Number
Knock Sensor #2, (G66) (Cylinders 3, 4, 5)

Reference: http://www.sjmautotechnik.com/troubl...g/20vcodes.htm
and the Bentley manuals.

This is very true, but you can have a faulty knock sensor and it not throw a code....
It does sound very much like a boost leak though...

[stevieyid]

At work this week and away for the weekend, only possibility is tomorrow evening 7.00 ish.

Cant make it tomorrow night. Now worries John we will sort something for next week. The general consensus seems to be a boost leak of some sort

[T2Andy]

Thats what problem i had steve,a few full boost runs it didnt want to know ,i changed my ecu with a differant map sencor and now pulling more boost and not one hicup

[stevieyid]

What map sensor do you have? A 3 bar map sensor?

[T2Andy]

Have you changed all the boost hoses ,i had a split under the throttle body hose ,very difficult to find .i did find these turbos start pushing everything to the limit,

[newsh]

Steve, pull the small boost pipe off the ecu cut a half inch off it and reclamp it the hose hardens and you can get a leak, pull the maf plug off and back on a few times, test drive. Check the hose from the WGFV to the WG for leaks. Have you checked the WG diaphragm?

[stevieyid]

I havent checked the WG diaphram as i dont know how. That was one of my thoughts considering the screeching at full boost to. Ill check the hose on the ECU and cut half inch off it.

[T2Andy]

I just got a feeling not all 3 bar map sensors are the same .(quality)

[stevieyid]

The hoses have all bee changed for Roose hoses so should all be fine

[stevieyid]

I just got a feeling not all 3 bar map sensors are the same .(quality)

Did Paul supply and fit your map sensor? Im sure its fine and the most likely cause is a boost leak however cant rule it out

[T2Andy]

If you put a peice of tube on the nipple on the wg\cap and suck it should hold the vacume .

[stevieyid]

Cheers Andy i will try that and see if it holds the pressure.

[T2Andy]

No paul didnt fit mine it was fitted by us ,i rectified all the possable causes of my cut out problem and was the last thing i changed ,was just a possability for you

[BRY]

Thats what problem i had steve,a few full boost runs it didnt want to know ,i changed my ecu with a differant map sencor and now pulling more boost and not one hicup

[T2Andy]