Does the 2004 engine perform slightly better than the 2003?

[Drag]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>if there were any change for '04 you can bet your ass that GM would have advertised that up one side and down the other, since mpg is the greatest weakness than the public can come up with for the H2.
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No, GM can't advertise that. The fuel economy figures are not posted on window stickers, because only the EPA can rate for MPG, and the EPA will not test the H2. So any improvement in MPG has to be determined by the owner. It's just that GM can't say anything positive or negative on MPG since the EPA doesn't test.

I have heard that the Vortec family of engines did receive some airflow modifications to their basic structure, and the engine in the H2 is a Vortec. Not a full generational change in engine technology, but at least an "improvement" I doubt that it's a programming change in the main computor or TCM, but it could be worth looking into your TCM chip for improving performance.

Nobody expects the Spanish Inquisition!!