Over this past winter, I had to do a bit of an unplanned repair. I was getting misfires in my #5 and 6 cylinders, and upon further investigation, I had found that the seal between the intake manifold and the head of the engine was leaking, causing coolant to seep into my spark plug cavities. I had also noticed some oil leaking in from the valve cover gasket as well, so it was time to replace both.
It seemed like a big job, and luckily a friend of mine came over to offer some guidance and 'moral support'. We steadily unbolted and disconnected everything. The one part that had intimidated me at first was the fuel rails. I had never dealt with fuel rails or injectors before. But they came off very easily, and as long as you are gentle with them, they should be able to go right back on without an issue. The worst part was a heavy bracket (circled in red on the photo above) which was bolted to the rear of the engine. Its sole purpose is to protect the drivers side fuel rail in the event of a crash. Once that was off (with a wrench, reaching in behind the engine), we were good to go, and the intake manifold came off fairly easily.
Being careful not to get any debris or coolant into the intakes, I cleaned up a lot of the old coolant which had been sitting in the valley of the engine block for a while apparently. I was quite surprised to see so much coolant in there.
I ensured that the metal where the seal was going to sit, was clean and dry before tightening the intake manifold back down following the suggested tightening pattern. Only then, did I notice an issue. The old intake manifold didn't have any holes towards the front of it, but the new one, and others I had seen at auto parts stores, did have holes for sensors. So now I had to find something to patch the holes with, and ended up buying some plugs from a local auto parts store.
I then proceeded with the work on the valve cover. I removed that and cleaned it up, before putting the new rubber gasket in place and re-installing the valve cover.
All in all the job took about 8 hours, including the trips to various auto parts stores to source out those plugs. The car started up, and ran rough at first. After a test drive to heat it up, I re-tightened the bolts on the intake in order to seal it in place, as per the instructions. I also re-tightened the valve cover.
I am still having intermittent issues with my Cylinder #4, in that it seems to be missing sometimes. I have tried a new ignition coil, but it is still missing, so I am suspecting that it might be the injector got slightly damaged, or that the spark plug is a bit dirty... I am not too worried about that, so long as the leaking is stopped.