my car hesitates or studders when under wot at either low or mid rpms? this is after installing my obx header and catless dp

nobody? bump

 

Any DTCs or CEL?

 

no codes at all

is there a possiblilty the header still needs to break in?

 

Did you erase DTCs -- even if you don't have any the factory service manual states that you must erase the DTCs when messing with the HO2S sensors to reset the learn values. It says that if you don't when replacing them you can damage them. Taking out a H02s and reinstalling it in something else will have the same effect. Disconnecting the battery does not do it. Try erasing and see what it does.

 

Manual or auto?..not sure if that makes a difference

 

Also....did you do the sparkplug anti-fouler mod on the 2nd H02S? Without the cat your 2nd H02S will give give you a CEL/DTC -- can you tune it out?

 

thank you for the quick response.... i didnt erase anything.. whats a DTC ... ill disconect the battery again and go from there

i didnt do anything i dont know why i dont have a code lol i wouldnt have had enough room for the non fouler and my 02 sensor

it can be HPT out... when i get that money lol

 

DTC is a trouble code that your ECM/PCM can set -- you have to read it with an OBD II reader (Autozone can read them). Normally you see a CEL but your ECM/PCM can have them stored without a CEL. Disconnecting the battery doesn't reset the learn values, only by erasing them with a "erase" feature on a scan tool does it.

 

yeah no codes i have the scan tool also.. but its weird its a big hesitation idk what its from it jerks you around when it happens

 

Doesn't make sense! If it is just the header and DP that you changed, you shouldn't have that problem.

Sounds lame...but are you sure both H20S sensors are securely connected?

The problem only occurs when you go WOT, correct?

 

it happens when i apply a load at about 2-4k on the tack.. its a good sized shake/hesitation.. then it just revs out all fine.. im going to be going to SMG on tuesday to take fred for a ride to see what he says... i still cant figure out this friggen squeaking/chirping noise that happens when i accelerate also>>> ahh idk

nobody else has any other suggestions!! i cant be the only one with this that happend...

 

I had the same hesitation under WOT and I changed my plugs and it fixed it

 

hmmm not a bad idea .... but my car has 4,000 miles on it .. ya know?

thanks for the post

how many miles did your car have?

 

mine had 43 000km, not sure what that is in miles.