Hi all I have checked this forum out a few times and think its a really great tool to help the DIY. I'm new so I may jack up the process, well here goes.

I have 03 X-Type 3.0 150,000 miles. The car has been fantastic. A few months ago I get the check engine light flashing and the little orange light car goes into crawl mode. I access this site and discover I have a vacuum problem the two o rings on the side of the intake. I fix the car runs great for two weeks. Then it happens again so I start the vacuum leak check again. No luck, I can't find a leak. I start reading threads and determine to replace the plugs, and coils and both intake gaskets, I clear codes and start again, a few miles and the next day in the cold the engine light comes on flashing then staying on, car goes into crawl mode. codes have varied but the latest is 306, 1314, 1316, 356, p1000 all coil, or misfire. I smoked the intake no leaks clear codes they come right back on. Getting frustrated does anyone have any ideas where to star? I'm guessing fuel filter, some bolt on sensors maf, Accelerator Pedal Position Sensor, I find it very hard to believe the o2 sensors would do this. Any ideas? Thanks Dave