Car dies after 4500 rpm, black smoke

[murat]

yesterday I went to a local dyno to see the engine figures for the my new RS2, engine oil and filter were brand new( 1 day old).

I was sensing that there was a problem but since I did not have the chance to play with the car on the road I didnt realized it was a big problem before the dyno test.

I will change the spark plugs but i think it will not solve all the problem. The car is giving a sensor trouble code, rpm sensor G28.

Is there anyone who can give some opinions about the matter?

[murat]

oh by the way car is a 95 RS2 with 120k kms. completely original, no modifications

[AAH!]

G28 is the engine speed sensor and is used by the ECU to determine the engine speed: if you are checking the fault codes with the engine off, this can show up as a fault, this is normal. If the engine was running when you did this test, it may be worth clearing the fault codes and trying again.

Also look here for more details: http://www.s2central.net
and more specifically here: http://www.s2central.net/motronic_02.html
and here: http://www.s2central.net/aby_ecu_codes.html

The car may be in limp home mode (the ecu preventing the car from boosting) due to sensor faults or malfunctioning components such as the MAF all of which vagcom or carrying out blink tests will help diagnose, www.s2central.net , will help you here.

It could also be the coilpacks, they can start to fail after 120k miles but you have only done 120k Km.

Do you have a boost gauge? if so what was the car boosting to? Maybe a boost leak, but this may not explain the black smoke.

Sorry to be so unclear, it could be so many things. Best to do thorough searches on here and on www.s2forum.com and try and rule out the easy stuff first before spending lots of money on replacing bits that you don't need to.

Also check here: http://www.sjmautotechnik.com/trouble_s ... boost.html
and here: http://www.sjmautotechnik.com/trouble_s ... 0vtecu.htm

Hope this helps a little

Angus

[alastairg]

If I understand you, the car is new (to you) and had an oil+filter change the day before. Check oil level ASAP. Was it overfilled and the black smoke oil passing out old turbo seals and being burnt off ?

[murat]

the smoke is not burning oil, previously i owned a polo 1.6 which i turbocharged myself, so i have some knowledge about the subject.
after the dyno test, i went to a local mechanic, and connected car to vag, the car gave errors like "rich mixture" and " lambda signal is out of range.

lambda sensor and maf sensor is brand new.

[alastairg]

Boost leak ??

Try this link, sounds like identical problem. Yes and you are right Black=fuel Blue=oil sorry

http://www.s2forum.com/forum/showthread ... lack+smoke

[murat]

ı will test the boost leak, what is the stock boost of ADU engine?

[alastairg]

Boost levels: stock is peak at 1.3 Bar (1.4 Bar when trying hard) dropping
to 0.8 at the redline.