Sorry for the long post. I'll start with the back ground: The car has 61k miles on it. Not sure what work has been done to the engine, but there is copious amounts of sealant on the valve cover so something has been done to it. Other than that, most everything engine wise is stock.

I took it to an autocross and a few rally crosses earlier this summer. during that time I noticed that when it ran at idle for a bit it'd start to smoke or give off a puff of smoke when you first get on it. This was written off as bad valve seals.

Two weeks ago I was driving to another rallycross. About 150 miles into the drive going up a hill at about 80 mph it stuttered and the engine started to shake. I let off the gas and started to pull over, but then everything fixed itself. Ten miles later I got to the rallycross and during the second run it did the same thing. Seemed like not all of the cylinders were firing. At the time it was thought to be a bad coil. I got the car home and started diagnosing the coil. Everything checked out so then I pulled the plugs. The plug on cylinder four had a broken porcelain insulator and was preventing it from firing and the plug for cylinder two had the ground electrode bent so that it was touching the center electrode. I replaced the one spark plug and regapped the other and everything seemed fine.

I drove it for about 30 minutes and all was good. On the way home I got on it a little more and it started running like garbage again. I pulled the plugs again and this time the ground electrode for cylinder number one was touching the center electrode. I thought that maybe the timing belt had jumped a tooth so I pulled the cover and everything seems to be lined up. Just using a flashlight to look down into the cylinder doesn't highlight any contact on the pistons, but something has to be hitting the spark plugs.

In the middle of all this I decided to do a boost leak test and a compression test. The boost leak test yielded a leaking intercooler which has been fixed and one other tube. Once that was fixed the only air leaks were from the oil dipstick and through the seal of the valve cover right by the half moon.

I was waiting for the patch on my intercooler to cure so I did a compression test on the engine while cold. It yielded readings of 165 165 150 and 165. I put a little oil in the #2 cylinder and the reading shot up above 200. Once I had everything reinstalled I warmed the engine up and retook the readings, the second time around I got 170 170 155 140.

My first test made me think I had bad rings on the #2 engine and would explain why I was getting air coming out of the oil dipstick. The second test makes me think I may also have a bad head gasket. This would explain why I'm either getting bubbles in the coolant or it's boiling even though the temp never goes above normal. This wouldn't necessarily explain why I'm burning oil though.

All of that aside, my car idles smooth unless you rev it up and let off the gas fast. It'll go below the normal idle, remain rough for a bit, and then go back to normal. I tried revving to 3K RPMs and then bringing the engine back down slowly and that seemed to stop the rough idle issue. Then I brought it up to 4k and 5K and both times it starting running rough prior to bringing the RPMs back down so now I have no idea.

Any thoughts or advice would be greatly appreciated.