So I bought a hatchback 5 speed that I had a buddy of mine looked at. He said looked good. Well turns out its had a engine swap, and now I have to get this thing to pass california smog. I keep getting a gas tank pressure sensor error, but I don't think this car came with one of those. I need to either locate one and install it so the computer will be happy, or locate a computer that will be happy without one.

It also surges at idle a lot. Especially when cold. If I block the cold air circuit, it gets a lot better, but will do it a little when its hot. Any help is appreciated.

I also need to locate the front suspension cross member(not sure of the correct name) to replace this one. And MAYBE convert this thing to power steering.

Tons to do, but I guess I have more time than money.

Thanks
Dave

p.s. I think this is a CX.

 

Welcome. I'm not sure exactly what all you can "legally" do, being that you're in California, so take any of my suggestions with a grain of salt.

Your P2P ECU is an OBD2 VTEC ECU, so that's good - it sounds like it matches the engine and chassis. What specific OBD code is it throwing regarding the pressure sensor?

Idle surge is due to unmetered air getting past the throttle plate. It sounds like your IACV is contributing to the surge, but not the whole story. Check for vacuum leaks. Check to make sure your throttle plate can fully close - that the throttle cable has some slack when not pressing the throttle.