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Q: My car starts to misfire really rough after running it for about 30-60 minutes, shutting it off then starting it up

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have gotten 8 codes. 1 says something about being lean on bank 1, other code says random misfire detected and 6 codes are each cylinder that have misfired. This only happens after running the car for a good length of time and shutting it off then starting it back up soon after
plugs are new, just changed oil, and timing belt has recently been replaced. My car has 170000 miles.
My car has an automatic transmission.

A: You have taken some great steps to try and ...

You have taken some great steps to try and resolve these issues. Looking to the spark system was a good choice. Plugs were a good start, but the distributor and wires may be causing the plugs to not receive the signal they need at the right time or voltage. You will want to check the spark at each plug, which can be done with a spark tester.

If this system is fine, you will want to look into the fuel pump and filter. Both of these can cause misfires if the fuel is not reaching the cylinders. Acuras built around this year have reported similar symptoms that have been cause by the primary O2 sensor failure. This would be the O2 sensor that is between the engine and the catalytic converter. Unfortunately, this is going to a process of elimination.

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