1999 Pontiac Sunfire "truck gets rough 45 mph" Questions

rough and I can't keep it at 45 mph it starts to idle bad at 2500 rpms the Car had new plugs and wires. I just replaced the Crank positioning sensor thinking that was the problem but it still is doing

...rough from 45 mph to 55 mph and once over 55 mph runs smooth. I notice from 45 to 55 the rpm guage moves with flutter or rough running engine. when i put in cruise control it smooths out. Flush will ...

engine was maybe miss firing around 45 mph running rough hesitating one day then fine the next now wont run at all sounds like its getting no gas Check for stuck open EGR valve or a bad MAP sensor.

...rough and low idle. when accelerating, the engine sputters and sometimes backfires. When it gets around 45 MPH it stops sputtering and drives fine. Does anyone know the answer to this problem? try ...

rough and back fires and shakes and hard to get over 45 mph you may have an issue with your fuel injection, it's called spider injectors, many times the fuel pressure regulator goes bad and dumps fuel

...gets louder as it goes up to 60 mph. As I decrease speed, the hum also decreases. I don't think it's there at all much below 45. Front Wheel Bearing Hub You will have to remove the brake ...

Truck runs fine until I get to 40-45 mph then engine hesitates and runs rough try changing your fuel filter. if you havent done a tuneup recently change the air filter too. People tend to overlook ...

...gets bad from 45 mph to roughly 60 mph or so, then it goes away. Frustrated, because the noise is so loud that you can barely talk to the person in the passenger's seat. Based on the other posts, I ...

...rough when in gear. Truck just started idleing rough and when I put it in drive it's really rough running and hard to get over 45 MPH. It only has 35,000 miles on it and has been sitting for several ...

rough/car shakes/resolves when idle increased to 1500 rpm. Car " misses" & hesitates on acceleration....also particluarly while crusiing at 34-45 mph. Engine runs fine at speeds of over 50-55 mph.