safc- check engine light hitting fuel cut

[DSMstud09]

Sup guys... well i've been messing with different values in my 2g GSX and this morning the check engine light came on. Now i've been hitting fuel cut around 3-4.5k it'll sort of like hesitate in that range and then once i get past there it'll be fine so should i lean it out in that range more??? And can anyone explain why my check engine light just came on all of a sudden. Check my profile for my list of mods... but i have evo 3 big 16g turbo with 550cc injectors upgraded in-tank fuel pump cams intake and 3"diameter downpipe 3" highflow cat all honeycombs still in right now in my injen intake i have my settings for High Throttle at 1k/-23 2k/-24 3k/-26 4k/-27 4.5k/-27 5k/-25 6k/-23 7k/-18 oh and i'm set at 16psi right now.

The car pulls extremely hard right now... but in that 3k 4kish range it hits cut and i've leaned it out to compensate for it... but it still hesitates in that range any suggestions??? should i go negative more in that range???

 

[steve]

Get the code read. Until you do everyone will just be guessing.

If you really are hitting fuel cut it's going to stop increasing revs not just hesitate. Your either knocking or missing.

When did you last pressure test your intake system?

 

[DSMstud09]

I haven't done that since i bought it... i've only had the car for about a month or so, but according to the a/f meter its running more on the rich side than lean.... so im guessing i have rich knock.... if thats the case... what do i do about that???? Also how do i check the Check Engine code myself so i don't have to take it to a shop.

 

[steve]

Most of the autoparts stores will do it for free or loan you the scanner with a deposit.
Make sure you get the actual "P-code" and not some generic text for the error.

Which wideband O2 are you using?

 

[DSMstud09]

autometer

I got the check engine code checked and its 4 cylinder misfire... so that means i need new spark plugs so i'm gonna change that out and see if it still hesitates. Wires look good.... they're magncor and they look new.

 

[steve]

Just to be sure, you have an autometer wideband and not just a AF blinkly meter connected to the stock narrowband sensor. What sorts of AFR number are you seeing?

 

[DSMstud09]

Not seeing any numbers it just lights up lean stoich, or rich. As i'm crusing it kinda jumps back and forth from lean to rich but it mostly stays rich the harder i press the gas pedal. Also i got the new spark plugs and its not hesitating anymore pulling like a champ again. The ones that were in there were pretty old.

 

[ziggo0]

Not seeing any numbers it just lights up lean stoich, or rich. As i'm crusing it kinda jumps back and forth from lean to rich but it mostly stays rich the harder i press the gas pedal. Also i got the new spark plugs and its not hesitating anymore pulling like a champ again. The ones that were in there were pretty old.

That would be a narrowband. At least the o2 is cycling, about the only useful info you'll get out of it.

 

[DSMstud09]

so should i get a wideband sensor??? I mean as you can tell i'm totally new to turbo dsm i've had a Esi talon for about 2 years before i got the GSX not only is it my first tubo DSM but its my first turbo car period. I think the fastest car i had before this one was a 96 h22 prelude i had and thats nothing compared to this car the torque and power in this car is amazing... i'll never go back. DSM FTW!!

 

[steve]

While a wideband is a useful tool it's not a requirement.
Now that we know that what your looking at is the output of the narrowband O2 sensor we can tell you that you should expect it to go rich under acceleration and lean on deceleration. During idle and cruise it should bounce back and forth while the ECU is running in closed loop.

A datalogger should be the first thing you get.

 

[DSMstud09]

Thanks man i'll def. look into getting one... any suggestions on what i should get????

 

[ziggo0]

I prefer the Innovative LC-1...the AEM UEGO is quite popular though.

 

[DSMstud09]

I know this is getting of my initial post but... does anybody know if the vr4speed intercoolers are any good??? Seems kinda too good to be true.... only 400 bucks for a intercooler that they claim to be better than a Hahn intercooler.... anyone have any pics with one... and also how does it perform... i'm looking to make only between 300-350 to the wheels... with my setup now i'm currently at about 270-280 to the wheels.... i was going to get a forced performance turbo manifold along with the vr4speed FMIC and be set at about 18 psi i'm currently at 16.5 psi i guess what i'm asking is it worth the investment or should i just go with a more expensive intercooler like a ETS FMIC????