I just replaced the pistons on my 2000 Si. Everything went smoothly, and the car is running great. The only problem has been when I get it up into VTEC. I can hear the changeover, and feel the extra oomph or whatever at first, but almost immediately after the changeover, it starts bogging, like a loss of power.
The motor is the stock B16A2, with CTR pistons, I/H/E and thats it.
I thought it might be the timing, but I checked it, and its fine.
It threw a code about a week ago, that was for the EVAP system, I'm don't remember the code off the top of my head, but I was told it was because the gas cap wasn't tight. But the more I thought about it, before I rebuilt the motor, I had a Vortech Supercharger on the car. When I took it off, I left the inline fuel pump that came with it on. But my thought is that it isn't functioning properly, and the car isnt getting enough fuel in the higher RPMs. Could I be right? Or is there something else I'm overlooking?

 

How is it tuned?

Why dont you just take out the inline pump and just leave the intank?

 

It's running on a stock ECU. And I'm going to take out the inline either tonite or tommorrow, depending on if it keeps raining. I'm just wondering if this is the most likely cause of my problem, or if there is something else that it could be.

 

make sure you have enough oil to

 

yea, there's definitely enough oil. I'm going to remove the inline pump right now. We'll see how it goes

 

check the spool vavle filter on the vtec solnoid. You can clean it with brake cleaner but realize that brake cleaner will deterate that seal and probably cause a leak later down the road. Also check oil and oil pressure.

 

This might sound lame, but, start small. Go back through all your grounds and wiring and starting looking for loose conections. Like the water pump ground. This one is a killer. If you don't find anything, throw a wideband in the tail pipe and see what your AFRs are. If you go WAY rich, there you go. If you are WAY lean... back out and figure out why you aren't getting enough fuel. Remember: You have changed the way your car is going to behave with a different pistion and C/R so that might be it right there. The stock ECU might be seeing knock and tossing fuel at it which is killing your performance. Then again, the inline pump might just be doing the same thing. My .02 .... Tuning is everything.

 

Well, I took out the inline fuel pump, and it's working perfect now