starts runs but hit the gas and dies

scan for codes and check fuel pressure with a gauge auto parts rent it

I have two codes, P0122 Throttle position sensor low power and P1496 5 voltage supply output too low. The van will start run and allow gas petal to be pressed without dying when the (brand new) maps is out, but not when it is in. We have looked for shorts in the wiring, front to back. Nothing! We have checked every sensor, every one is good. We are soooo lost. Please help!

Where is the 5 voltage supply wire?

for the first code you really need to read the tps sensor voltage with a scan tool. also check for a vacuum leak at Map sensor and or any vacuum leak as well as bad grommets in the engine like pcv 1495 code may be the evap solenoid in pic or a leak in the evap system which has to smoke tested to find leak. see pics. first three pics tell how to test for 021 code.