Take it back to the dealer if you still under warranty. I had the same problem, throwing P0171. Turns out it's the wastegate actuator. They replaced it for free.
P0500 indicate problem with your VSS (vechicle speed sensor). Basically is your instrument cluster or PCM lost signal from the VSS.
First, verify your VSS sensor located around the transmission housing is working. Then verify if you got signal at your PCM pin #58. The wire might be lose when...
I don't have an Greddy gauge but usually, that wire is for the signal. That's the analog signal that read from 0 to 1 v, or 0 to 5v for a wideband. It should either hook up to a module that connected to your gauge or either connected directly into your gauge.
If you don't know what the trouble code is, it's hard to determine what's wrong with it. Just pray that they know what they are doing.
I had a broken mid pipe and it took them 2 months to order the right part. Some of them just don't know what they are doing. Keep calling them and have them...
Interesting. By reducing the length, I don't think you going to get much of the response time since electron travel so fast. But you will reduce the resistance of the cable. Also make sure you get for corrosion because that's what really effect the circuit.
Let us know how it goes.
BTW...
That's awesome. Are those parts included in the GB price? I am cool even if we have to pay a little extra.
Also, since we probably need the kartboy hanger as well, why don't we get a GB on that as well.
Does anyone know where we can get the best price for Kartboy hangers?