Truck starts and idles fine, but when I put it in gear and try to accelerate, it has no power. I've changed the fuel filter, fuel pump, spark plugs, distributor, coil, coil wire, plug wires, even the carb assembly. What else could it be?

 

Send a copy of your post to support@avproecm.com. My 92 b2600 had the EXACT problems yours does. They fixed mine 3 years ago, and it has been fine. I highly recommend this company. Check out their web site also.

 

Carb Assembly??? any Mazda truck built after 1988 didn't have a carb, they're all EFI..

Anyways, your problem is the either the ECU is on its way out, or you could have a plug cat converter, or your timing is out..

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