Running lean with a high idle, any ideas?
 

I have a 98 GT that currently is throwing the PO171 and PO174 running lean code. The car tends to idle high if you drive it a little rough. If you take the car to 3,000 rpm for a shift, as soon as you push in the clutch it will stay at 3,000 rpm. If I turn off the car and start it again, it will idle fine for awhile. I have replaced the fuel pump, fuel filter, spark plugs, wires, coil packs, cleaned the injectors, cleaned the throttle body and still no change. I am currently running a cold air intake, off road x pipe, with flowmaster 40s. Not sure if the O2's are telling it to run a certain way or not? I'm looking to buy an SCT Livewire tuner to see if it will make a difference and check my air to fuel ratio through that. Any ideas as to what my problem is are greatly appreciated! thanks!

vacuum leak or maf sensor dirty or bad

thanks man, I will give those a try and see if that fixes the problem! I will keep you posted