My RX8 is a 2004. I'm having an issue with the car chugging (jerking/missing) at 80 mph to 90 mph at constant pressure on the gas pedal. If I give it gas the chugging stops. I do not experience this at any other speeds. Another interesting thing, it the car is in cruise at 82 it is fine until I head up a slight hill then it does it again. I have pulled the plugs and they are fine. I also have changed all four ignition packs. Suggestions? My thought process is to change the pug wires next! Also if i go the plugs are the Nology plug wires worth the money? Thanks

Monroe

 

No the nology plug wires are not worth it go to www.mazsport.net and get their plug wires. Trust me

 

Check the rear O2 sensor.

 

Thanks for the plug wire info. Are the plug wires from factory or performance?

The O2, can I test it without replacing it? Another question, the exhaust is 3 1/4 inch Greddy with not cat. Will that affect the back O2? Thanks for the help

Monroe

 

I had the same problem once with a Ford Aerostar. Tried tune-ups, plugs, etc. It always came back about a week later. Ended up it was the Throttle Position Sensor.

Mike