Well i have not tryed this on my 03 ecsb but when i had my 98 zr2 my gas milage went from about 18 on the hwy to almost 21. and intown went from about 14.5 to a little over 16. I didnt think it would work either but it worked for my old s-10, but on the same note when i traded in the turck i gave it to my mother (which has an 00 blazer zr2) and her MPGs didnt move at all. they stayed the same. I think it helps but not on all vehicles. A friend of mine just put it on his 98 yukon and he hasnt noticed a difference. But yes it did work for my s-10.

 

stick that in yur pipe, hahaha testimonials, these do help try one, buy it at checker auto keep your receipt and return the **** if it dont work,

 

It works on carbs (given its going straight into the carb) but not on fuel injection.

The suction from the fuel injection disrupts the spinning air flow. Also air/fuel isn't mixed in the throttle body on fuel injection.

It is however mixed in the carb. So it should work with a carb or older tbi engines given the air is coming from straight above.

However I wouldn't waste the 60 bucks. Thats what they cost over here.

 

maybe my isuzu needs one...

 

oh wow my old thread came back from the dead, my take is try it, keep the receipt and use it for a month, it dont work for you return it for a magical fuel atomizer, or some other gimic but as long as it is returnable why not try it.