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Q: I'm having a horrible lack of power issue

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It started out with being slower and slower to start and then some hesitation, then all of a sudden when I was driving up a hill it started backfiring out of the intake and maxing out at 3000 rpm, if I hit the gas slowly it runs rough but tops out at normal rpm but if I hit it normal it maxes at 3000, now it doesn't even have enough power to get onto ramps. Since this happened I've replaced the distributor cap, rotor, pickup coil, crank sensor, and the timing chain, none of which helped at all, it has been throwing different codes some to do with the crank sensor, some with a lean condition, some to do with the o2 sensor circuit, I'm not sure if it's related but when filling the fuel tank all the way up it leaks a big puddle once I am done but it doesn't leak after. I've tried everything I can think of and nothing is working so that's why I am reaching out to see if someone else can figure it out

My car has 160000 miles.
My car has a manual transmission.

You may have a problem with your evaporative emissions system. Your car has a small purge valve called a purge solenoid that controls the venting of fumes from the fuel tank as these fumes build up inside, particularly when you are refueling the car with gas. The EVAP system prevents fuel vapors from the fuel tank from escaping into the atmosphere. The EVAP system collects and temporarily stores the fuel vapors in the charcoal canister. The charcoal canister is filled with activated carbon pellets that can absorb the fuel vapors. When the engine is running, the fuel vapors are purged from the canister and burned in the engine. The vent control valve (solenoid) controls the flow of outside air in and out of the charcoal canister. The vent valve is controlled by the engine computer (PCM). Normally the vent valve is open. It closes when the engine computer tests the EVAP system for leaks. If a leak in the EVAP system is detected, the Check Engine light will illuminate on the dash and the trouble code related to the problem will be stored in the engine computer. When an air leak is present in the EVAP system, the MAP sensor will not be able to determine the air density, and the MAF sensor will not be able to determine the volume of air, entering the engine correctly. This will lead to an over fueling situation or an under fueling situation depending on the size of the air leak and engine operating speeds and load. This may eventually lead to catalytic converter problems as well as misfiring problems. I would recommend having an expert from Your Mechanic come to your location to diagnose and inspect your vehicle.

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