i have two stock chips laying around one is from an 88 2.8 and the other is from my 89 iroc 350 tpi auto...i dont know which is which and i want to take the hypertech chip out the iroc...im have problems getting it started thats why i want to switch back

 

Need the code off the chip, it should have 4 letters and 4 numbers. They're listed in the FAQ I do believe. That or post it here, someone can tell you.