Im getting error code 51.... tps basically ... would this make the car stall after throttle? also i only have about 16 inches vacuum at idle... basically no leaks thinkin timing is off a little bit.... recently did a head gasket... any help

Yes, a bad TPS has been known to cause stalling after you let off the throttle. It could be one of a few things.

1) Simply needs to be re-adjusted
2) It's actually bad
3) Your throttle plate is sticking open slightly, thus the ECU doesn't detect the IDL contact (for idle)
4) Your throttle linkage is sticking.

First, check the easy stuff, throttle linkage and plate. Make sure they're not sticking, and that the plate closes all the way. Next, go on to check the TPS via the TSRM. See here:

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=100

Also, your vacuum seems quite low. You should be looking for around 20in/hg.