Mechanics

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1990 Mazda b2600 • 4 cylinder 4WD Manual • 150 miles

I have a 1990 b2600i mazda. Changed fuel pump and filters and changed plugs cap and rotor with wires. It just backfires out the tail pipe.I did check to make sure wires were not crossed. HELP.
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Dlizar
December 17, 2010.




Do below to determine if its fuel or spark problem

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if so, check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, coil's resistances, cap and rotor, distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing
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Rasmataz
Dec 17, 2010.
Fuel pump comes on and there is great fuel pressure. Spark at #1 plug is yellow not blue.

Tiny
Dlizar
Dec 17, 2010.
Ignition is weak-test the ignition coil

Rasmataz
Dec 17, 2010.

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