Problems with P0505, two codes showing up?

[XpL0d3r]

Also the manifold and thermostat housing are both off of the manual.

You kept the IACV on the manual, right? Making sure, because if you swapped the one over from the automatic, 99-00 IACV's are different between auto (3 wire) and manual (2 wire).

I agree with the others on checking your throttle cable. Pull your intake and take a look at the throttle plate. Make sure it's fully closed. I know you said you cleaned the IACV, but if the throttle plate is dirty, clean that up too.

I had a P0505 issue with my RSX last year, along with an idle higher than normal. I cleaned / replaced IACV, checked the cables and hoses, etc. It turns out the TPS was off calibration.

 

[Erny]

So I'm kind of putting some puzzle pieces together because the original motor over heated for a pretty substantial amount of time and either that or something else warped the Intake Manifold and wasn't seating on the gasket right and therefore caused a vacuum leak.

 

[Erny]

it wasn't extremely warped or anything severe we ran a bead of rtv around both sides of a new, cheap O'Reilly gasket. Waited til it got tacky and tightened the nuts and everything looks nice and sealed. Going to wait for the RTV to finish doing its thing to test it tomorrow afternoon.

 

[Erny]

I've also found that a 12mm ratchet wrench makes removing the manifold much easier.

 

[Restotech]

From my experience, gas eats or softens most forms of rtv or silicone. Due to the injectors being so close and gas passing by the gasket I wouldn't think this would be a lasting solution.

 

[Erny]

So the leak is still there but it's a lot smaller than it was, i saw someone was selling the whole head and I was wondering if it would be worth it just to get a new head gasket in there aswell as get rid of the leak, or should i just get a new IM

 

[Erny]

problem solved! The IM support was loose and causing the manifold to tilt downward & didn't let the gasket seal right, torqued everything down and tested with carb cleaner, everything is running fine so far. thanks for the help guys!

 

[XpL0d3r]

Use a torque wrench to tighten the IM and TB nuts and bolts to spec.

It appears that this was the solution to the problem.