First off, is the AFR gauge hooked to a wideband O2? If not, it's completely useless. If so, your idle AFR should be trying to stay around 14.7, if the car is never able to maintain an AFR around 14.7 there is something wrong mechanically. An AFR of 17 at idle is indicative of a leak after the MAF housing.
A leak like that which throws off AFR's can easily cause a lean condition would could cause the misfires AND potentially damage the engine. I would not drive that car until you get it all sorted out.