Hi

All was well untill about a month after fitting it.
since then, when ever i put my foot down it seems to cut out at about 3-5 k.
The exhaust is now fully decatted.
I have been told that it could be over boosting?

What sort of damage could this be doing?and could it have done damage already?

Is it right that if i keep off boost then there wont be a problem?

Could this be the time for a remap?.

And is there a way of telling if the engine has been damaged?

Cheers for your replys

Dannytwo.

 

You may be getting boost cut due to reduced back pressure,just a thought!?

Tim

 

same thing happened to me when i got my clasic wrx de-catted,
first time i nearly sh%t thouht id killed it.
i got told it was over boosting dew to more sudden power gain through de-cat.
anyway take ur batery leads off over night then tae it out slowly to a nice open road the in every gear go through your gears to controlled but hard right up to 5 and put ur foot down
you are teaching the car your new powerband if you like .like self learning again.
anyway i did that then i never had any problems again ran ok.

 

Thats just lucky.

All this does is resets the ecu, this wont prevent fuel cut and it wont make your ecu learn a new powerband. All this will do is reset the ecu to the factory default map which has the most aggressive timing etc, and when you run the car the ecu will use its knock sensor to retard the ignition etc to match the fuel that you are using. The fuel cut will still come in at the same preset limit, the only way of changing this is by fooling the ecu by using something like a fuel cut defenser or a remap/aftermarket ecu.

 

It does sound like overboosting and therefore hitting the fuel cut. The fuel cut is there to help prevent damage to the engine, so it shouldnt cause any damage to your engine but some people may disagree with that.

Does the engine still drive okay when not on full throttle? if so probably no damage whatsoever. Also is there any smoke billowing out of the exhaust? if not again dont worry.
You could have a remap depending on what car it is and how far you want to go mod wise, a cheaper option if you just want to leave it as is, is to fit a manual boost controller. You can use this to just turn down your boost a bit, which will prevent you from hitting the fuel cut limit.

 

It's most likely the cold weather and the decat combining to make the car overboost mate, IIRC you get a passive boost increase from decating the car, which probably by itself wouldn't be enough, but combine it with the cold weather and bob's your uncle! Does it happen when it's particularly cold out/ in the evening?

I've heard keep having the fuel cut come in regularly is not particularly good for your car as it's not a subtle intervention, but I doubt having it happen the odd few times will result in any damage. Might be best to drive it off boost till you can address the problem though.

An excuse to have it remapped I'd say! :-)

NS04

 

Do you think a remap will cure it?
As i would'nt want to have it remaped to find it was still doing it.
Is there any other reason this could be happening?

cheers
dannytwo

 

Yes a remap will cure it. There are, I'm sure, other possibilities, but the decat and cold weather are most likely IMHO. Also, a remap will give you more power and torque cause it will exploit the better exhaust gas flow from your remap and it will be tailored to your particular car meaning a nicer drive all around. Choose your mapper carefully though!

NS04

 

remap the way to go !but for the mean time get a dawes device setting the boost below fuel cut and then it wont spike, visit their web site it shows diagrams on how to install to prevent fuel cut.

 

When i have it mapped i'll go with Mr forrest apexi power fc is the way to go.

 

Al, it may help if you give these guys some more info.......

import stb forrester turbo 1997
just had full engine rebuild at API ( run in now )
had a decat d/p bodged by **** mechanic and then done by a proper mechanic and car's not run right since fitted all the exhaust bits and rebuild.

I don't think that an ecu reset will solve the problem as it's a MY97.

Si.