Advice for darkest Africa on weird RS2 power!?!?

[urRS2]

Hi

Jozi Town in darkest Africa calling!
95 RS2, stock (so I am told) with a 76mm decat pipe.
95 octane with NF Black octane booster.
New air temp sensor.
Turbo removed and resealed and refitted/ boost leaks checked.
Cleaned MAF.
VAGCOM checks done today with following error:

00561 - Mixture Adaptation
13-10 - Adaptation Limit (Mul) Not Reached - Intermittent

Dyno done about 2 weeks ago.
See attached hub dyno curves and boost curves - in red.
(vs Subaru STI 22B in blue)

What gives at 4000 rpm!! (Lots of black smoke). What to check in order of likelyhood would be great!! I have the 561 "Possible Causes of Fault" but perhaps someone else out there will be saying "I know exactly what the problem is!!" ???

Thanks

[VaudiGR]

check on the S2forum.com there is a thread there talking about what to check for that code.it can be a lot of things: Maf,lamda,some bad connection,WGFV,an air leak...

basically the boost pressure seems ok for overboost.It should hold at about 1.0bar to the red line.If it is stock that is

[alastairg]

Black smoke=overfuel=boost leak=ecu 'sees' too much unmetered air & pours the fuel in. Next

[Lloyd]

Yep, boost leak. Been there had that one! Try to use a 98 or higher petrol too.

[DickyC]

Yes, that all sounds horribly familiar.

Have the turbo's plumbing checked again. Mine was leaking in two places at once; the main turbo to intercooler pipe (which must have a proper name if only I knew it) and the diverter valve.

[urRS2]

Leak checks have been done by "the man"
but
best I do the checks again!!!!

Thanks every1

[VaudiGR]

also check the wastegate frequensy valve...that is plastic and if not been changed for a while,might not be working properly

[alastairg]

also check the wastegate frequensy valve...that is plastic and if not been changed for a while,might not be working properly

That would not create black smoke due to Xs fuel. It just feels flat as there is only mechanical boost ~0.4 bar. Mine went two years ago so BTDT

[VaudiGR]

sometimes if the WGFV is leaking,it is there when you have the boost leak.The valve itself might not be broken

[urRS2]

Hi

Thanks for the feedback. When we did the VAGCOM checks the N75 was OK. Still have not done a boost leak check...

For another perspective...

Had my stock (?) RS2 vs another stock (?) RS2 (both cars have 76mm decat) on the Dyno this morning. I was running 95 octane with NF black octane boost. He was on pump 95.
We are at 1600m above sea level here.

No more black smoke!! But see the curves...both have flat power curves!?

There was a big difference in the curves up to 4000rpm but they behaved quite similarly after that?? I suspect that the slight difference in the high rev range may have been the octane booster?

Is the similarity after 4000 coincidence or is that stock behaviour for this altitude perhaps? Or have both cars got the same problem!?

Has someone been messing with my "stock" ECU!?

[VaudiGR]

the biggest mistake is running on 95octane pump gas.The manual says to run on that type of gas only if you need to!!! So imagine if you had 95octane gas and it wasnt as good as it is supposed to be,and it ended up being 93octane rating due to varius reasons.

Also,octane boosters dont do any good either.By excessive use you may end up doing more harm than good in injectors and seals.
I would suggest that you do a boost leak test(although if your car is reaching 400Nm of torgue and stays flat it means that it is probably a fuel related problem.The fact that you have a good exhaust doesnt mean that you will get more hp all the time,and dont forget the car is 14 years old and if no engine modifications,big service etc has been done a small compression loss may end up loosing some power down the line.

How come you are useing a 76mm decat and not a KN filter,or anything else?Just decating without remapping wont give you any more gains either.Perhaps you will get some better exhaust gas temperatures,but thats all

[urRS2]

Thanks for the input.

At this altitude (1600m above sea level) we only get 95 octane so we have to try and deal with less oxygen and cr4p fuel!!

Torque is supposed to be flat and Power should peak - here it is the other way round!

Before I do anything in terms of the ECU I am trying to establish a foundation that I understand to work from - I have only had the car for a few months.

[VaudiGR]

well on the original map of the RS2 boost if being reduced from 1.5 and 1.6bar to gradually 1bar or 0.8bar.So it is understandable why the torgue curve is going down rather than flat.And since that is happening,then the rest is obvious

[urRS2]

OK...so in your experience what should a stock standard boost curve look like? What boost & revs should a stock RS2 be doing at peak power?

[VaudiGR]

i dont remember excactly cause my rs2 always had a chip on it.here is a grafh i found of a chipped one.Usually the power goes down after 5000rpm on the rs2 cause the boost gradually goes down

http://www.tots.ch/rs2/rs2/tuning/bilde ... portec.jpg