I cannot say for sure for your model year, but I think the OVP is located just in front of the firewall on the passenger side.

If your car has been sitting, I will suspect your fuel filter. Dirt may have settled and clogged your filter and hence rough running. You may start there first.

Next I will suspect moisture in your fuel. How much gas did you have in the tank prior to starting your car? If your car has been sitting that long, moisture may have build up in your fuel line. Just a guess.

If your engine has only 30K, overhaul will not even be considered. You have practically a new car. It is probably some minor maintenance items you have over looked.

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95 R129
04 Infiniti G35.5 BS
10 X204