PVT_Rod_Fitzwell

Hi everyone, this is my first post here. I've owned my 2003 A4 Quattro 1.8T for almost a year now and have 200K miles on the original motor and trans. The previous owner didn't keep up on proper maintenance of the car and I have dumped over $5000 into it so far. I paid $3900 for it. I think he covered up several things, lied about others, and generally screwed me over. Immediately after purchasing it, I had to take the rear passenger's side door apart and replace the plastic piece that the cable attaches to so the window can move up and down. The alarm horn stopped working since battery acid leaked out and ruined the circuit board and the crankshaft speed sensor failed the second week I had it. The oil temp sensor was bad as well. To give you an idea of the way this guy did things, the windshield washer reservoir was leaking (he hid this from me as well. I thought it just needed washer fluid). Instead of taking ten minutes to find out where the leak was and why it was leaking, he took that lousy putty that comes in a cylinder shape and you knead it until the outer and inner layers are well mixed, then press it into and around the hole or crack. After 24 hours, it's hardened. He put it all around the bottom and around where the two pumps are but the leak continued so apparently he gave up and conceded defeat. It took 10 minutes to jack up the car, remove the wheel and plastic shroud, and unbolt and remove the lower reservoir. The headlight washer pump had rusted, seized, and eventually split the plastic and underlying metal, allowing fluid to leak out. I pulled the useless putty off, some of which wasn't even attached to the tank, pulled the washer pump, and plugged the hole until I got a replacement pump. I have replaced all front and rear control arms, shocks and struts, tie rods, several coolant hoses, the "j" plug, which was the source of a very difficult to find coolant leak, and other things here and there.
Finally, the time came where I had to replace the half-moon and timing chain tensioner gasket, valve cover gasket, and spark plug tube gasket. I removed the engine cover, the upper intake, what I assume was the EGR tube, PCV hose, heat shield and attached tubes on the left of the motor, spark plugs, coils, and wires, fuel injector wires, and the stuff on the top rear of the engine. I also removed the plastic cover on the front of the engine and the 2 hoses (a coolant and an oil hose going to the turbo) in front of it. From there, I had easy access to get the valve cover off. I noticed significant buildup of oil, carbon, and gunk in one of the tubes that ran along the passenger side of the motor. I used carb/choke cleaner and a toilet snake to clean it out. I proceeded to remove and clean the valve cover, the surfaces where the gaskets sit, screwed in the cam chain tensioner tool, removed the blocks holding the intake cam, and removed the tensioner gasket and half moon. Once everything was clean, I installed the new half moon and tensioner gasket. While I was screwing in the 3 torx screws holding the tensioner, the center one snapped. I was using my torque wrench at 84 in/lbs or 7 ft/lbs. There's no reason that bolt should have snapped unless the previous owner over torqued and caused catastrophic fatigue of the metal. The outside 2 were fine. I put everything back together but I don't know if there is a specific way I should have reassembled everything involving the intake cam and order of the bolts. I unfortunately was forced to get Bosch platinum ir fusion spark plugs since the good old copper core ones were out of stock. Once I had everything done and started the car, I could tell that it was running rough and it sounded like it was going to die. I left it for the night and put my old plugs back in this morning in case the new ones didn't agree with the car. As soon as I started the car, a loud and disconcerting, rapid knocking noise was coming from the area of the cam timing chain tensioner. I freaked and shut off the car. I immediately tore everything back apart. Any insight, help, or advice that anyone can give me would be greatly appreciated. Btw, I did mark the chain, gears, and several reference points and made sure that everything lined up before putting it back together.

PVT_Rod_Fitzwell

Quick update-I took everything apart and couldn't find anything visually wrong. I put it back together and it started and ran okay for about 4 seconds, when the noise came back. This time I got a check engine light, specifically p0011 - powertrain "A" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)
This is what I was afraid of when I removed the clamps that hold the intake cam down so I could get at the cam timing tensioner gasket and half-moon. Anyone know how to fix that issue?

John535is

Sounds like either the chain it out a tooth, the belt is out a tooth or the tensioner has collapsed.
Prior to starting all of this was the engine running OK or did it have low power, stumbling issues on acceleration? Assuming the engine was running OK prior, then the original timing is assumed to be OK before you started and you would have done the markings on the chain etc. If you are confident you reinstated it after the broken bolt incident, then I would be looking at the chain tensioner. It may have collapsed, the guides may have broken off or it's got fouled up stopping the oil from pressuring it.

You may also need to do a check that there is nothing else floating around in the top of the head, give it a good clean, if you think the previous owner has already been in there, check for debri that could foul the valves .


Did the cam chain tensioner put tension back on the chain when you released the tensioner tool?

PVT_Rod_Fitzwell

Good call. Chain tensioner could be pressed down by hand without much effort. Replaced it and everything is good now. On a side note, I am working on a prototype build of a new armrest with thermoelectric heating and cooling built into a 2 soda can cup holder. I have 3 solid ideas for an armrest build, 2 for up to 6 cans in a glove box cooler, and 2 for the back seat built In the spot where my ski bag that I will never use currently sits.