Hey all,

My '99 S70 (NA base model) has been acting weird for the last week ever since I came back from the Import Meet at Carlisle. Upon departing the Carlisle field, I noticed my Check Engine light came back on. It had originally come on during the trip up that morning - however, I had a club buddy read my codes for me with his scanner before he reset the light. The codes were these: P0135, P1017, P1053. I thought that when he reset it, it would stay off. But when I left that evening, the light came back on, and it's stayed on for a whole eight days.

Ever since, I've noticed some strange things happening with the car: At one point last week, upon starting it in the morning when cold, the engine seemed to stumble and sputter, almost as if it wanted to stall. I had to put it in park and increase the idle very slowly with the accelerator in order to stabilize it. It only happened for 30 seconds. And the other day, when coming back from Maryland (a 90-mile round trip) on the parkway, something happened that scared me - At highway speeds between 65 and 75, for no given reason, the engine thumps and shakes as if it wants to break itself off its mounts, and I can feel the accelerator pedal vibrate without a doubt. This will happen about every 10 miles - I have to let off the gas, and when I push it again ever so slightly, the thumping and shaking disappear. My guess is that one of the cylinder ignition coil wires is going bad, like what happened five years ago, or that the plugs need to be changed.

Any advice is needed - but I need it quick b/c I'm due to go on another long trip this weekend. Thanks guys.