After putting a DP and MP on my friend's '89 TII, he developed some problems, like slow revving, no power, and insane fuel consumption. We changed all of the vacuum lines, just to be safe, but it didn't help anything. We checked the ECU for error codes and go the following:
30 Solenoid valve - split air bypass and 38 Solenoid valve - accelerated warm-up system and air supply valve, neither of which I have dealt with in the past. Anybody know how to deal with these, and if they can cause the car to run very rich? (3 MPG and burning eyes if you're near the car while it's running.)

 

those error codes wont cause the car to run crappy. Id check around the air control valve for vacuum leaks. Double check your vacuum routing again. Even though you probably didnt touch the tid, check it anyway.

 

Thanks for the reply. We checked and double checked the TID and it looks good all around. Next time I go over there I'll check the ACV for leaks, and convince him to get a block-off plate for it.