Q: My 2004 mazda b3000 is idling rough and has a loss of power. Engine light is on. Spark plugs and ignition coils have been replaced

asked by on December 04, 2017

My 2004 mazda b3000 is idling rough and has a loss of power. Engine light is on. Spark plugs and ignition coils have been replaced. The problem improved but still remains. Engine light is still on.

The diagnostic test showed the problem is the ECU. However, I called another shop, and they felt this might not be the problem as if the ECU failed the truck would be dead.

Do you have any suggestions as to what this could be?

My car has 69000 miles.
My car has a manual transmission.

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