2002 Mazda Tribute ES V6 @ 65,750 miles. 1) I had two exhaust manifolds replaced (cracked) but still faint odor of exhaust in cabin. Mechanic cannot find leak. EGR failure? 2) While testing idle and RPM while in neutral, I discovered at 4K the engine knocks terribly and the RPM sticks around 4,200. This does not happen when I test drove it in L2. Any idea what it may be?

SOURCE: 2000 mazda miata r&r throttle body

se if egr is controled by vacium or electric
if it is by vacium then locate the egr solenoide and make sure it has vacium in one hose w/ engine runing if it does then replace solenoide

SOURCE: 2002 mazda tribute es

check to make sure #5 spark plug wire isn't bad,make sure you have not wired it wrong from changing plugs. You should purchase a chilton manual if you haven't already

SOURCE: engine light on mazda tribute 2002

Have it checked again and see what code it is. if it is P0401 it is probably the sensor shown below, The DPFE (Diferential Pressure Sensor)sensor is usually mounted on the engine and is connected to the pipe that runs from the exhaust manifold to the EGR valve with two rubber hoses. When the sensor goes bad, the Check Engine light comes on and typically sets any or all of teh following fault codes: P0171 & P0174 (lean codes), and/or P0401 (insufficient EGR flow). Nine out of ten times, the fault is not a bad EGR valve or a vacuum leak, but a bad DPFE sensor. A replacement costs about $112 at Ford, or about $48 at an aftermarket auto parts store.I hope this helps.

SOURCE: I own a Mazda 2003 Tribute LX V6 3.0L. The other

check your engine and battery ground wires and the fuze links.

SOURCE: i need a diagram of a 2001 mazda tribute engine ,

Get a haynes manual they are priceless. Check out Ebay