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Truck miss firingf on take off

My 1997 Chevy blazer is miss firing on take off. I have changed the plugs and wiring. Was told that the ogygen sensors may have effect on my problem is this true.

I would check for a dirty throttle position sensor before looking at the O2 sensors. The air flow sensor may be dirty and also check the air filter.

If the O2 sensor is causing this problem then it’ll probably show up as a error code. If electrical is eliminated then look at a gas related problem.

what are the fuel trims reading?

me.

On a 12 year old truck, it’s time to replace the fuel filter.

Oxygen sensors would sooner provide you with clues to the cause of misfire than actually BE the cause of misfire but it’s not impossible because they do wear out.

If you changed plugs and wires, a plug not firing would result in unburned fuel igniting in the exhaust. So you might check the condition of each plug (wet or dry, clean or carbon-coated. Also check that each plug is firmly seated to rule out a vacuum leak at the plug. Misfires related to lean mixture can be caused by vacuum leaks, including an EGR valve stuck open.

Is your check engine light on? If so, it would help to have the diagnostic trouble codes read by one of the major parts chains or a shop. A common misfire due to a lean mixture can be caused by any number of vacuum leaks, including an EGR valve stuck open.

Oxygen sensors would sooner provide you with clues to the cause of misfire than actually BE the cause of misfire but it’s not impossible because they do wear out.

That’s NOT the first time I’ve heard that…but I’ve yet to wear one out…with 4 vehicles over 230k miles…3 of them over 300k miles…NEVER had to replace a O2 sensor.

When you replaced the wiring, did you replace the distributor cap? Look beneath it for fire traces that look like pencil lines between the pins.

Never wore out an oxygen sensor. I’m gonna guess that all these cars are between 85 and 95 model years - after they started making better oxygen sensors, but before OBD2 which is real particular about old, slow-responding oxygen sensors. I ran the one in my '91 Volvo for over 200k and when I did replace it, the problem turned out to be the heater circuit to the oxygen sensor, rather than the sensor itself.
My OBD2 cars (three BMWs) start complaining about their oxygen sensors at about 100k miles.

I’m gonna guess that all these cars are between 85 and 95 model years

NOPE…87 Accord…96 Accord…90 Pathfinder…and a 98 Pathfinder.