cant fix stumble
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cant fix stumble
My na s5 has a weird stumble at a very light press of the throttle when your trying to maintain a constant speed. the car runs strong. But it seems to pop and buck.Just replaced the maf any ideas thanks
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Feedback System code means the 02 sensor isn't being read by the ECU, which in turn means the ECU isn't going into closed loop. Fix the 02 sensors wiring. See the local series five FSM for how to correct fault codes.
A larger than stock fuel pump will overwhelm the stock FPR and force more fuel thru the fuel injectors, even though the fuel injectors is opening for the same amount of time as with the old pump. How much more fuel?? Got me, but it will be more than with the stock pump. Enough to cause your problem? Got me, never done that.
Or put another way.......the FPR is controlled by the vacuum put on it. It has no way to know you put a higher output fuel pump in, so it still opens only as much as it did before. The FPR was designed for the stock pumps output, not the higher output pump.
Still, I'm not saying the higher output pump is the problem.
A larger than stock fuel pump will overwhelm the stock FPR and force more fuel thru the fuel injectors, even though the fuel injectors is opening for the same amount of time as with the old pump. How much more fuel?? Got me, but it will be more than with the stock pump. Enough to cause your problem? Got me, never done that.
Or put another way.......the FPR is controlled by the vacuum put on it. It has no way to know you put a higher output fuel pump in, so it still opens only as much as it did before. The FPR was designed for the stock pumps output, not the higher output pump.
Still, I'm not saying the higher output pump is the problem.
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