B6 3.0 2002
I have just purchased a non-running 3.0 B6.
The engine cranks over but doesn't start.
I'm getting codes P0347, P0342, P0392 and P0367 which is Crankshaft Position Sensor Circuit Low for all four of the sensors. I can't believe that all 4 sensors have simultaneously gone bad, so this obviously means something else.

The previous owner mentioned that the car had been overfilled with oil and shortly after that it quit. The timing belt is tight and every now and then the car makes a very weak attempt to fire up. Any ideas where to start?

Mark

 

Check timing, these cars can throw these codes when the timing is off.... Pull the valve covers and see if it's on marks, you will need special cam lock tools to do that, but there is a way to tell approximate if its off allot... Email me and I'll send you pix...

 

I dismantled down to the timing belt today.
All around the toothed Crankshaft pulley, the timing belt ribs were totally destroyed.
It was pretty obvious once I rotated the engine to TDC and the camshafts didn't move!!
Ok, so now I've got to inspect the heads.
Alsp, I'm trying to lock the crankshaft with the locking pin tool T40026 before I remove the camshafts, but from the Bentley diagram I can't for the life of me work out where the locking hole is!
Where is it? on the front, side? The diagram might just as well be the inside of my dishwasher as far as locating components go!

 

If you talking about crankshaft lock tool, you could go with out of that tool. It a big bitch to put it in.... It's on the left side bottom of the block towards the back a little over half way...
Just put the crank on top dead and rotate the camshafts, make sure when you rotate it the valves don't get damaged, so if you feel that it doesn't want to go anymore you have to stop and move the crank either way to move the pistons away from the valves...
So rotate the cams and see if all of the lifters touching the cam lobes... Is some of them don't go up all the way that means the valves are bent, if they do put a new belt on and check compression...

 

OK, thanks, that's really helpful.
(Re Pin lock tool, That's left side when facing the engine from the front?)

So one more probably obvious question. How are the camshafts turned when the sprockets are off? I see there's a flat spot in the middle where I might possibly get a 19mm wrench on or do I have to put the sprocket back on and use that?

 

left side is the side of the car=driver side

you could use what ever you have to turn the cam shafts, i use Chanel locks (obviously you cant grab the cam lobes with it ) just use two Chanel locks to turn and hold the cam...

 

I put the sprockets back on and turned them with a 18mm socket taking care to avoid piston collisions. They all rotate OK apart from the passenger intake camshaft which is really stiff even when the cams aren't pressing down valves. It suggests that this might have caused the timing belt to lose its teeth. I guess the heads will have to come off. Don't know if that means the camshaft has worn badly in the head or vice-versa. Can a head be machined to accept a new cam or is the head trashed when this happens?

 

I finally removed both heads.
The intake camshaft on the left bank looks like it had oil starvation on one of the journals, hence the camshaft almost seized causing the timing belt to shred itself.
The journal is deeply scored in one place with matching roughness on the camshaft.
One valve was bent and stuck open and there were 3 marks on the piston crown where the inlet valves had impacted on one cylinder.
I'm not sure what caused the oil starvation.

On the right side everything looks fine with no collision damage and all valves appear to close correctly.

So the right head I assume will be trashed. So now onto the fun of getting the left head into the machine shop and finding a used LH head.

 

If your belt snapped chances are that's what caused the biggest issue, could be that it skipped on the left head while it was still running on the right head but not pumping oil... Could have very well have been your oil... POST PICTURES OF THE CARNAGE! Just for the wow factor. Good luck rebuilding, sounds like you are underway to a new engine.

 

Was there a solution my 2002 a4 is having the same problem