Hey guys n girls,

n00b question here....my 05 STi has borla hush catback, K&N Typhoon, HKS DP, HKS UP...however, when I miss hiting a gear by taking it to redline and no shifting, it cuts my rev-band down to a lower RPM and the CEL comes on...

just wondering, I know that it's probably my HKS DP as I have had my typhoon on for quite some time before it and no issues....therefore...I heard it the CEL will go away with a tune....but is this kind of issue normal when taking it to/past a bit of redline???

To take the CEL off....I have to disconnect the negative battery terminal and reset it.....is doing this too many times bad? Does it decrease the life of my ecu ???Heard you can only reset it 100 times or so....is this true?

Last question, will the COBB AccessPort help? Will it fix that CEL problem if I tune the car with it to a Stage 2 STi map???

Thanks, any comments would be appreciated!

Get the AP. It will most likelly get rid of that CEL and give you some great power gains. You are ready to go straight to STG 2.

You can reset the ECU as many times as you want. Infact it's good to do every once in a while. You're thinking of reprograming the ECU with a basemap, which you can only do 100 times or so.

You're probably getting the CEL because the HKS downpipe removed the cat... Go by pepboys or autozone or whatever you have when your check engine light comes on again and have them pull the code. If its P0420 (i think thats the code - search on here) its because of the dp. I fixed mine by getting the $50 Perrin o2 simulator fix that you splice in between the ecu and rear 02 sensor... its ratehr easy to install and then you have all options of EM open since some won't allow you to turn off certain warning lights (like the UTEC - its either all or none)...

Most likely you're creeping with no EM while running a dp. COBB's AP will help with creep and allow you to clear CELs.

thx guys, gonna grab an accessport!

Have you tried getting the CEL read to see what it is?

^^^The only sane post so far.

You can reset the ECU as many times as you want. Infact it's good to do every once in a while.If you need to reset the ECU all the time, something isn't right.

Get the code read so you *know* what is really happening.

Infact it's good to do every once in a while.

there is no need to reset the ecu of a properly tuned and mechanically sound car. in fact, arguements can be made that it does more harm than good.

there is no need to reset the ecu of a properly tuned and mechanically sound car. in fact, arguements can be made that it does more harm than good.

Sane post #2.

See also:
http://forums.nasioc.com/forums/showthread.php?t=935336