Karl... I had problems with my TPS on my 2TGEU.... You can run the motor without the TPS and it will run without a problem.. I know this because I ran mine for 6 months without it.. Until it mysteriously decided to work.. You can probably test it that way. I'm only going on if you have a standard computer.. I'm not sure about aftermarket.. The TPS switch on the 2TG's aren't the same as the 4AGE, there not varible? (not sure if thats what you call it). The TPS switch on the 2TG only tells the computer if it is at full throttle or at idle. The engine will also run without the AFM, I wouldn't recommend it because it runs rich as.. But it is one way to test it... Just a side note... Apparently there are 4 different computers, and 4 different AFM... I only can think of 3 for the 2TGEU's.. I have 2 of the computers and can safely say there completly different.. Maybe they will run the engine when you mix and match but arent happy?????? What computer are you running??