08-03-2012, 08:03 PM
Hey guys, 2002 trans am. A4. Long tubes, new o2s, new plugs and wires, ory, no rear o2s or air or cats. Lid. Car has 160k on it, and its starting to have a hesitation, and no power when I mash the gas. It'll hesitate, and not spin tires, and feel super sluggish. Fuel pump? Fuel filter? I'm sending the computer out, could it be due to the stock tune? Would love to fix it lol.
08-03-2012, 08:49 PM
Is the check engine light on? If at some point you caused the car to revert to an open loop fuel trim with your mods it'd be running pig rich and would foul out plugs in days or weeks rather than years. Fouled plugs on top of running really rich would cause the hesitation and power loss you describe. Running in open loop for whatever reason would cause your CEL to illuminate though.
Headers and no cats without a tune can also cause cars to run rich leading back to the fouled plugs theory. These factors might not cause the CEL to illuminate.
The fuel pump theory is also a possibility considering the mileage of the car. It wouldn't be the first thing I checked though.
Pull one of those new plugs for me and post a picture of the electrode/porcelain if you would.
08-03-2012, 08:51 PM
Ok I will. I have a scan gauge and I actually think it might be in open loop.
08-04-2012, 08:31 AM
The scan gauge is saying the car is in closed loop. I get a p0140 p0160 p1133 and p1153 code, ever since the header install.