New Tune Resulting In 30 Rwkw Less

[CK34GT]

Morning all,

2 weeks ago i had my gearbox / clutch replaced and had the guys re-tune the car too as it had been over 3 years since my last tune, with another tuner.

The new dyno sheet showed the car at 193rwkw, which concerned me as my last dyno tune back in 2007 had me around the 220rwkw mark.

When i questioned the new tuner, he put the difference down to the fact others "tweak" their dyno settings to give off false readings. i had heard of people doing this in the past but surely 30 rwkw is quite a large "tweak" in settings. Isnt it?

I gave my new tuner the benefit of the doubt. However, the car feels much slower as turbo response times are now very laggy. At times it feels as if i am driving a NA car as i cant feel the punch of the turbo i once used to feel. The boost just doesnt put me back in my seat like it used to.

The tuner did carry on that the new tune is a "safe tune" but in all honestly the car felt quicker before i even had the Power FC installed.

Now on top of the above, the fuel economy has become very poor. Coming from a minimum of 350km a tank prior to this new tune, my first tank out of the workshop came to 190kms. Keep in mind the driving has been kept rather sensible as i am still wearing in my new clutch.

Am i right in assuming the tune is attributing to the poor fuel economy i am experiencing? Makes me wonder why this is happening as the car is noticably slower too.

Do you guys have any suggestions before i go back to these guys and complain? These guys are very well known in the industry and have a good name so i find it tough to go back to them and complain about their work results.

Current mods are :

3.5" turbo back exhaust

FMIC

K&N Air Filter

Apexi boost controller (high setting at 12 psi)

Walbro Fuel Pump

Power FC

Spitfire Coil Pack

Appreciate any advice guys, as i am at rock bottom at the moment as i have just spent over $3k to have my car eating more fuel and driving much slower.

Thanks

Con

[Guilt-Toy]

190ish rwkw is the normal kw to expect from your car. 220 seems a bit tooo much. forget the number. its about how the car drives.

[The Dan]

It can only be the tune or the car.....either way the dyno is there to tell you. The fuel consumption is not normal so just mention that and take it back to have it checked. The tuner can't fix it if he's not aware of the problem. You may kill two birds with one stone

[blind_elk]

Do you have a copy of the "old" tune? Then re-install those maps. Or the previous tuner should have a copy.

The economy - check "closed loop" has been turned on.

Driving / performance - maybe it's simply psychological, the number is lower so you expect the performance to be down as well.

[MrR33666]

what are the afrs on the new tune compared to the old tune?

[CK34GT]

thanks for the responses guys.

How do i check if "closed loop" is switched on? is this checked on the PFC hand controller?

AFRS?

BTW i spoke with my tuner breifly this morning and his advice was to continue driving the car for another week and monitor the fuel consumption as it could be a fluke. (sounds to me he couldnt care less TBH)

Edited September 22, 2010 by CK34GT

[paulr33]

193rwkw is bang on for std turbo. mine made 192rwkw with a good tune

your economy should be 350kms to a tank and some dynos will give higher readings

ie moving the air temp sensor is enough to inflate your reading from 190rwkw+ to 210rwkw+ so take it with a grain of salt

and for what its worth your better of making less power and having a quicker car vs havingt more power on an inflated sheet

to check if 02 feedback is on

read the powerfc faq in my signature and use the online emulator also in my signature

if your economy is 190kms to tank its likely 02 feedback is off (turn it on)

[Dose Pipe Sutututu]

or most likely the tuner didn't give a rats arse about rows 3-15

[Rolls]

Peak power sounds right but if the economy is that bad it is possible it is a sloppy tune hence the lack of response, feeling down in average power. Could take it back or take it elsewhere, bit of a gamble really as we have no idea who the tuners are.

[paulr33]

if 02 feedback is working and turned on, you dont need to tune every cell to get good fuel economy

it certainly helps, but its not the be-all and end all if working 02 feedback is ON

[Rolls]

if 02 feedback is working and turned on, you dont need to tune every cell to get good fuel economy

it certainly helps, but its not the be-all and end all if working 02 feedback is ON

how lean does the O2 feedback tune it anyway?

[wolverine]

if the light, light/medium load points of the map are left very fat then it will probably be thirsty regardless of O2 feedback being on in my experience.

[paulr33]

02 feedback aims for stoich 14.7 by default

you can change it with datalogit

[CK34GT]

193rwkw is bang on for std turbo. mine made 192rwkw with a good tune

your economy should be 350kms to a tank and some dynos will give higher readings

ie moving the air temp sensor is enough to inflate your reading from 190rwkw+ to 210rwkw+ so take it with a grain of salt

and for what its worth your better of making less power and having a quicker car vs havingt more power on an inflated sheet

to check if 02 feedback is on

read the powerfc faq in my signature and use the online emulator also in my signature

if your economy is 190kms to tank its likely 02 feedback is off (turn it on)

From what i can see, i must check the 02H setter and make sure it is switched on right?

and can i change this from my PFC hand controller if it is turned off?

Cheers

[nuclear_skyline]

193rwkw is bang on for std turbo. mine made 192rwkw with a good tune

your economy should be 350kms to a tank and some dynos will give higher readings

ie moving the air temp sensor is enough to inflate your reading from 190rwkw+ to 210rwkw+ so take it with a grain of salt

That is one area that I agree with. The car shouldnt be returning such a poor fuel economy. I had my gtst with a hi-flow and very similar mods making 230rwkw and I was always getting close to 500km/tank.

Something is not right, I have not the experience or knowledge to say what that is, and I would be getting the tune looked at. Maybe one of the experienced tuners on here could have a look at your tune file if you upload it?

[CK34GT]

ok just ran down to check the settings on th PFC....

Sensor Check Screen:

I found that only IGN and ECC was on (filled black circle)

Everything else was off (empty circle)

Function Select Screen (as below)

Boost Control, air flow warning, injector warning - OFF

Knock Warning & O2H F/B Control - ON

I dont get it, if O2H in the sensor check was off, why is the O2H F/B Control showing on in Function Select Screen.

How do i actually switch the O2H sensor on in the Sensor check screen - this should likely fix the fuel consumption problem right?

Edited September 23, 2010 by CK34GT

[CK34GT]

or most likely the tuner didn't give a rats arse about rows 3-15

This makes sense as only IGN and ECC (line 1 & 2 i see) is turned on and all remaining lines off.

Any thoughts on what this could mean?

What is the importance of lines 3-16 ??

Edited September 23, 2010 by CK34GT

[JonnoHR31]

02 feedback aims for stoich 14.7 by default

you can change it with datalogit

no, you can change which cells are trimmed under constant throttle, not how much they're trimmed by.

OP, he means rows 3-15 in the fuel map, nothing to do with the sensor screen. whilst on that screen tho, what does the o2 voltage show at idle?

for it to be using that much extra fuel just from the tune he'd have to go through every cell and richen them all up and take out loads of timing under light load, which would just be silly but you never know...

[femno]

Unless the tuner is really SHIT i doubt they would go through and change everything to make it really rich...could be wrong.

Coincidence, but failed Fuel Pressure Reg?

Depending on how they can sometimes fail it could make the thing rich under low load and lean on power...or rich everywhere = sluggish.

Take it back and get them to SHOW YOU while cruising on the dyno that the AFR meter shows either 14.7 or 1.00....shouldnt be anything other than that....

[boostn0199]

With this o2 sensor when you turn it on and off in the power fc controller which jap word represents on is it the one with the dots or the one without?