Cel is on, I ran the self diagnostic from the green clip to neg on battery, no codes flashed. I then went to delete the code by unhooking the neg on the battery, pressing the brake pedal and then starting the car. Nothing changed. My car just got back from the shop. it seems to run fine, no stuttering or anything scary... I just want to know what's up so I don't nd up blowing up a new engine...

 

1990 S5 ..( in future please post your year and series so you can get help faster.)
I'd bring it back and let the shop deal with the CEL on,they should have seen it!
I mean they did work on it,right?

 

well, the cel didn't come on until I got it home... Also it lost a bit of oil pressure at op. temp, but the oil is full.... oil psi was just under 30

 

The codes that were thrown I thought were a 12, then a 1, but double checked and it threw a 12, and a 10. 1 one flash, two short. pause, one long flash. I think I fixed the issues, and then I tried to clear the codes from the ecu and started the car up.

Then this started happening. wtf?

http://www.youtube.com/watch?v=xaK5AEZy20o

 

car is a 90 na. only mods are hks intake, header, ss braided oil lines and clutch line.

 

what did the shop have to fix to get your car back running before this issue?

 

According to the FSM a 12 is the TPS's full range sensor and the 10 would be the intake temp sensor. Make sure the intake temp sensor is plugged in. That's all the ECU is looking at in that case.