Originally Posted by
blo0d Hey Miko, which TB are you using with that mani? I have a q45 TB on my custom intake and I am encountering some nasty hesitation (bucking) below 3000rpm (mostly when cold) when I try to slightly open the TB... could it be the TB is too large?
Currently Im running 3" piping with a coupling to join the 82mm q45 tb
The reason why this is happening when the car is cold is because no one is changing the start up MAP. So what is happening is the car is running lean because of to much air is coming in because of the large TB. When the car is hot the car is running off of the O2 sensor. When the car is cold on start up I think the car runns off of a predeturmend set program. You have to see if you can change this.
I bet if you richen up the mixture with a FPR this will go away. You will most likely have to go up about 10-15 PSI. Once it runs good at cold start up you can then now tune the car for the richer mixture.
or
try and find if the start up map and see if you can tune it.