b6a418t

Greetings folks,

I recently acquired an 04 a4Q which had 72k miles on it. So I decided to work with a buddy to get the timing belt replaced.
Replaced the belt/wp/tensioner etc. but seemed to have messed up timing a bit.

While replacing the belt, the sprocket/pulley attached to the cam moved a bit backwards (anti-clockwise). We were concerned
about it but figured if no interference is felt while hand cranking the motor everything would be ok.

Put everything back together, now car cranks a lot before starting up and I can see a P0341 code indicating wrong timing.
Car runs/idles fine but I can feel the lack of power.

I searched through various forums and think this is what needs to be done.

1) Remove belt from the sprocket.

2) Have the cam sprocket (the large one) line up to tdc. To do this, I am planning on removing
all the plugs/coils to motor turns easily. However, I read it's not recommended to turn the top
cam sprocket on its own. Is that true? Is there an alternative way to accomplish this?

Note: the bottom sprocket with the 19mm bolt did not move at all during the installation.

3) Assuming using a screw driver we figure out TDC and the notches line up (valve cover and sprocket) put the belt
back on again. No need to remove the hydraulic pin tensioner or the tensioner pulley.

Does that sound right to you guys? Also I am thinking the entire lock carrier does not need to be removed. Just
moving it 3-4 inches will let us do this.

jwj

You basically have answered your own question. I have changed tbelts on this car enough times and that cam sprocket can be tricky when putting belt on, (as it wants to move about a 1/2 tooth) when putting belt on. On way I do it is move the cam gear 1/2 tooth in opposite direction and when belt goes on it lines up perfectly.
Sometimes teeth on belt line up perfectly and no problems, sometimes I move a little to line up.

Yes, you will have to remove belt and align cam gear with notch, (make sure it is lined up and not off a little like you have).
The fault code your getting is the camshaft positioning sensor, (G40) is not getting proper readings and your performance will die as you are not getting the proper timing advance. Plus, you may have exhaust/intake vales not seating and you'll lose power there too.

Do not take out the spark plugs- This is a waste of time. If you turn the timing gear a little either way it does not matter as long as it lines up with mark. However, your crank turns twice to the cam once so if either gear gets turned then you will have to find TDC and re time cam and crank, (which is not what you did).

b6a418t

Thanks for your input mate. Much appreciated.

I will post back after I take care of this issue.

Big turbo TT

You should have made timing marks with a white paint pen to help you make SURE you put the new belt on correctly.... I am a profesinal and do this all the time and use paint pen on the pulleys and belts to make sure everything lines up and the job needs to be done ONE TIME.

Big turbo TT

Sorry........"professional"......I pressed enter before I read it.

b6a418t

He he! This is the first time both me and my buddy did a timing belt job. Live and learn I guess.

So attempted to remedy the problem today but ran into issues getting the tbelt loosened. Loosened the tensioner pulley and the hydraulic pin pushed back up! So I am guessing I will need a new hydraulic pin (and some coolant as it's definitely easier working with the lock carrier moved out of the way.

So anybody have any suggestion as to how to get the tbelt loosened at this point?

Situation I am in now:

- tensioner pulley is loosened
- hydraulic pin pushed up a bit
- tbelt is tight so no way to move it off the teeth

b6a418t

BTW, this is probably a stupid question.

How important is it to make sure the bottom sprocket had lined up as it was originally?

I am asking this as while lining up the top (large) sprocket, the bottom might be moved a bit. We do have marks showing the original location in the bottom sprocket.

jwj

You HAVE to make sure both cam and crank marks line up. Take off the bottom cover of the crank and you will see only the crank gear, (there is a mark on both gear and casing). I will send you a pic if you do not see, (jwj500@earthlink.net)

Remember, the crank spins twice to the cam once. So, as long as the crank has only moved a little in either direction, then just turn back to center mark. Make sure cam and crank marks are lined up and complete.

As for the tensioner. If the pin has pulled out, put the tensioner in a vice and slowly compress tensioner back so you can put pin in it. This may take up to 3-5 mins as you cannot force this. Just do it SLOWLY.

To answer your question, if you do not line up crank and cam marks, (first, your engine may not run) and you may have your pistons hit your valves and cost you much dollars.