got two codes p1676 p0420 , need advice please

[turbolence46]

Got a 6spd 96 nsx with a high boost ctsc. The tcs button doesn't seem to light up or anything when it's pushed (not sure if it's supposed , just got the car) but these CEL just popped up. I only found a few things about it any advice on the best way of diagnosing this tcs problem would be appreciated. We don't have have smog here so the catalytic converter issue isn't as pressing.

 

[docjohn]

how did the car get a six speed? how many miles on the engine and blower?Any other mods like i/h/e?

 

[turbolence46]

The 6 spd was swapped by the dealership at around 20k miles, it does have CT headers, CT intake, CT clutch, and exhaust. 106k miles on the engine, I cant find any record of when the blower was put on so it might have been at first purchase, it's been serviced with new bearings and belts a few times in its history.