re. '89 200q solved, well er um sort of + timing belt & distributor & cam sprocket

[Ben Swann]

John,

Sounds like you dodged the bullet on this one.

A couple things:
1) Adjusting the belt  will change the distributor orientation, possibly
throwing the hall sensor "out of window".  The ECU will generate a code for
this, but you'll want to check/change the distributor orientation so the
hall sensor is a close to the center of its window anyway.

2)  You'll want to verify that the notch on the crank pully lines up with
the TDC mark on the flywheel as seen through the window in the bell
housing.  These can and do slip, and you may want to cut a new notch with
cold chisel to facilitate getting the timing belt back to proper alignment.

3) As you know, it is ok to be off a half tooth in one direction, and you
can select the direction in which to err. based on whether you want your
perfomance on the low end, or high end of RPM spectrum, if you like.

4) The proper mark in the cam sprocket is a notch cut in the back side,
which is no where near the dimple found on the front, and sometimes there
is a dimple on back too, or notch on the front - probably for 4 cyl motors,
but I don't know, just don't use them.  If yours doesn't have the notch in
back, maybe someone replaced the sprocket, but I have not seen one without
the notch in the right location.  I have some laying around that I replaced
with adjustable cam sprockets if you need one.

5) I've found it good to check the engine is at TDC(using a rod in the #1
spark plug hole + crank pully mark + TDC flywheel mark).  Then make sure #1
exhaust and intake lobes are up/valves closed.  With that, the distributor
should have the rotor pointing near the #1 position as when the cap is
installed.  Then you should be in the ballpark for starting.

6) Maybe you want to consider doing the water pump/timing belt job since
you are this far.  You don't have to though, and I have managed to slip the
belt on and off with correct tension without lostening the pump, though it
is tricky, and you sure dont want your belt too loose again.  advantage of
doing the belt and pump now is then you shouldn't have to touch it anytime
soon.  I know - you probably just want to get it running to sell at this
point, but use this as a selling point, as people do appreciate that this
major service has been addressed.

I'm sure there is more I forgot to mention.  You'll surely want to get it
running so you can at least sell it.

Ben

[Well actually today was full of good new folks.  I sort of stepped away
and back to the basics, about all that I recall from my MAE 328 class (very
little) is an internal combustion engine runs on the famous 3 things, fuel,
spark, compression.  In order to get a couple of these together correctly,
well perhaps all of them on an OHC engine, the fuel, spark, and valve
opening and closing of course got to be in time with the crank.  So I
figure as fuel smelled ok, lets have a look at the cam timing.  Now
admittedly I had been a slacker and not done this when I got the car, th
inking that crap the thing wouldn't run if the idiots that had installed
the engine had the belt on wrong.  Of course that isn't quite true, the
VW/Audi 4 and 5 will run about 1 tooth off either way albeit poorly.  So I
pull the cover and feel the belt first off and it is limp, way limp
compared to how it should be.  So I turn her over by hand a few times
(establishing TDC with a feeler probe in 1 BTW, is there any way to see the
stupid crank pulley mark with the bumper on or am I being obtuse?) and lo
and behold the cam timing appears to be 3-4 teeth off, ouch...

So I reset the cam timing (I think) turn her over carefully by hand a
number of times, crank her with the hall sensor pulled for about 30
seconds, then check compression all round, all good, better in fact than
when I had got the car, whew....  Start it up, idles and runs  beautifully,
take her out, no more off idle "lag" and pulls right on up to 1.5 bar.  I'm
SO happy but I'm not quite satisfied, I've left the timing cover off, and I
look things over and actually I'm still about one notch on the cam gear
short of where in my experience with 5 cylinders the mark should align with
the head.  Now that is a sort of bogus alignment, prone to personal
interpretation but still.  So I advance it the one notch and, nothing,
won't start at all again.  Now this is all again right about as it is
getting dark but I also notice at that point something further confusing.
 In my past experience with
the 5's in my Quantums, EVs, and Audi 100 motor the timing mark has been a
square sort of mark.  This pulley has no such mark, instead has  two dots,
and I had been using the first dot I came to when I set it.

So I go looking at some other pulleys all 4 cylinder VW and some have a
mark on one side and dot on the other (for head and timing mark on belt
cover or for use as the idle shaft sprocket) one has a couple of dots like
this one, one has only a mark.  So what is the deal, what should my cam
timing mark be?  The answer I will persue in the morning will be to simply
pull the valve cover, establish TDC then establish the cam position by
inspection of the lobes, hopefully this will be one  tooth back from where
I am, where it ran well, and roughly sort of where one of the dots is.  I
assume the entire set of problems with this car has been that the timing
was initially set incorrectly or it was set but with the belt much too
loose, it jumped one notch before or maybe even after I test drove the car
as it did not hve the problems then.  Then when I got it briefly under
better boost the other day (the temp sensor corrosion probably was part of
the picture,) I figure when I shifted
into 3 and stood on it, it jumped a couple more, and than rapidly stopped.
 Explains my put, put, put as well.  I guess I dodged the bullet pretty
well on this one, don't often slip a 5 cylinder belt without making a
piston meet some valves.  Anyway good progress was made today, and my
Michelin Man is still just fine 8-)

Thanks to everyone who has been of help, oddly enough I'm going to look at
another this weekend so this car may still well end up as "parts" for a
much lower mileage early '89 with much more appealing pearl white and black
leather.  I mean why be pissed at only one of these things I figure.

John
janders1 at mix.wvu.edu]