Page 1 of 2

Power Loss at high rpm

Posted: February 28th, 2012, 11:05 am
by movo
Hi Steve and gang

I seem to be having a problem with my car at higher rpm both stock and when versatune is loaded. I was hoping that you guys could help me out before i head off to the dealership to get this fixed. I need as idea of what to tell them is wrong with the car. I've attched the logs that i've done with the car stock and with the base 95EU map loded at the coast and at night. The dynosheet is with the base 95EU map loaded. The car also seems to be really heavy on fuel. I get about 340km driving decently on a full tank.

Power Loss at high rpm

Posted: February 28th, 2012, 12:12 pm
by Kevin
Hey bud, hope Steve can shed some more light on your problem. As I said on the MOCSA forum, it seems as if your wastegate is working way 2 hard. With u being at the coast the turbo should boost less to make the same kinda power we make at altitude. Have u tried reloading the base 91US / 95UK map just 2 see what it does?

Re: Power Loss at high rpm

Posted: February 28th, 2012, 1:38 pm
by Steve @ VersaTune
Check for a boost leak. What are your LTFTs like? heavy minus? Edit - looks like actual and desired AFRs are pretty close at high rpm, so maybe not a boost leak.

Could be the recirc valve (BOV) blowing open, wastegate not closing all the way, severely clogged air filter, or damaged turbo.

The ecu is calling for more boost, but the turbo can't make any more. Either because it is not able to get enough air into the turbo, the turbo is damaged, or the air the turbo is putting out is not reaching the intake manifold.

Re: Power Loss at high rpm

Posted: February 28th, 2012, 2:23 pm
by movo
Thanks guys

The guys at MOCSA mentioned that it could be cos the wgdc is running at 95-100% The car is actually fine in low RPM. With VT, its even better at low rpm till about 5000 then the power goes down. I dont hear any funny noises or feel anything weird just a loss of power at higher rpm. The mocsa guys mentioned that the car seems to be boosting ok at about 1.15 bar stock and 1.2 with VT from the logs. But with me being at the coast i dont know if that is a bit high. Does this mean the turbo is fine supplying the boost but the engine is not getting it? Luckily my car is still on warranty so i can get them to replace stuff :biggrin2 i just need to flash the car back to stock and give them a story. What should i tell them is happening?

Re: Power Loss at high rpm

Posted: February 28th, 2012, 2:27 pm
by movo
Kevin wrote:Hey bud, hope Steve can shed some more light on your problem. As I said on the MOCSA forum, it seems as if your wastegate is working way 2 hard. With u being at the coast the turbo should boost less to make the same kinda power we make at altitude. Have u tried reloading the base 91US / 95UK map just 2 see what it does?
Thanks dude. I havnt tried that map as yet. I'm guessing if the car is faulty when stock it might be even worse when VT is loaded :(

Re: Power Loss at high rpm

Posted: February 28th, 2012, 2:27 pm
by Steve @ VersaTune
The turbo normally runs out of breath around 5000-5500 depending on tune and mods.

Re: Power Loss at high rpm

Posted: February 28th, 2012, 2:32 pm
by movo
Steve @ VersaTune wrote:The turbo normally runs out of breath around 5000-5500 depending on tune and mods.
What should i ask the dealership to check for when i send the car in stock? other guys on the same dyno are pushing out 170wkw without any software and just exhaust and CAI (MK 2 MPS) as mods

Re: Power Loss at high rpm

Posted: February 28th, 2012, 2:49 pm
by Steve @ VersaTune
What mods do you have on your car? You're not missing the requested load targets by much. You're hitting typical flow numbers for a stock car in warm weather.

Re: Power Loss at high rpm

Posted: February 28th, 2012, 5:18 pm
by movo
The car is still stock. No mods at all. Can't do any except software untill the warranty expires. Those logs were actually taken at night but its summer here so air is still warm at night with the humidity at the coast

Re: AW: Power Loss at high rpm

Posted: May 5th, 2014, 5:03 pm
by Bane
I know this thread is very old. But could the problem be fixed?