P1515 Error - any thoughts?

[luvmy911]

Hello all:

I have a 2003, 996 C4S. Approx 53k miles. And important to note, a TPC Super-Charger installed too.

I get a P1515 (Intake Manifold Switchover 1 Short Circuit To Ground) error code about every 50-100 miles.

I notice a few newer issues with a bit of a rough idle but it clears up after I reset the CEL. Next, I think I am getting what I imagine is Vapor Lock, where the car does not want to start after I have been driving and the engine is hot. I am not sure if this is related to the CEL situation or if it truly is vapor lock from possibly the Super Charger.

Is this CEL P1515 truly a situation where I have bare wire that is shorting out? If so, does anyone know where I start the hunt for this bare wire?

Any help appreciated! Thanks.

[JFP in PA]

Actually, P1515 on that car is the code for the throttle body return spring malfunction (not closing in the allotted time). Probably related to being supercharged.

[luvmy911]

Is the spring replaceable? Or am I talking a whole new throttle body?

And thanks for helping clear this up on the P code. Everything I found on here said otherwise.

[JFP in PA]

Originally Posted by luvmy911

Is the spring replaceable? Or am I talking a whole new throttle body?

And thanks for helping clear this up on the P code. Everything I found on here said otherwise.

The spring just may need cleaning, along with the throttle body, not uncommon. But I do not beleive you can get the spring by itself.

On the subject of codes, the meaning of the codes changes with some model years and DME software versions, so you can find more than one meaning for a given code; the one I gave you matches the car information you posted.