Engine Performance problem
2008 Ford Edge 6 cyl Front Wheel Drive Automatic 20,118 miles

I have a fairly big problem. I leased a 2008 Ford Edge and had the oil changed once, or at least I thought I had at a local car wash. Went to Ford Dealership March 31st 2009 at approx 17,000 miles for 2nd oil change and they informed me the factory filter has never been removed. To top it off, I just got a check engine light and found out some cam phaser and VCT Solenoid pull codes POO18 AND PO021 and they want to remove/teardown the entire engine to check for sludge. $1,700 which I can not afford. its running fine, but idles rather shakey and the dealership just told me if i could live with the chk engine light on, keep driving it until time to turn it in at end of lease. Does anyone have any suggestions or ideas they may wish to share with me that may resolve the issue that the dealer has not mentioned. I appreciate any and all input.. thanks