Timing woes

[scuby]

I've read what seems like all the posts.

I've watched all the videos.

I've done at least 50 timing belts in my life.

I cannot for the life of me get my 2001 2.4t to not throw p00016 cam/crank position error.

Previous owner did a head gasket 20k km's ago.
Check engine been on since I bought it. He couldn't remember if it had been since the head gasket.

Runs fine.

Spent 6 hours last night trying to tackle it. My exhaust cam with the Vvt loaded up (spring type vvt) will only settle in half a tooth off. As if my timing belt won't allow the correct distance between the cogs.

I'm using a cam locking tool. The Vvt unit was replaced with the head gasket, it moves freely and looks new. I've replaced the selenoids with a known good one.

The cam marks will stay where they were set after two rotations. But like I say, always a half mark off. Is that enough to trigger the cel? Could it be something else?

Is my belt stretched due to improper install before? Seemed a bit tight but actually looks just fine. I'm grasping at straws. Anyone?

[abscate]

If you have a reader or VIDA which report cam flank angles, you can actually measure how much you have to move the belt and which direction to move it. See ‘ cam flank angle ‘ thread in the p80 forum here

I, too, spent 8x getting this right in my T5.

viewtopic.php?f=9&t=96631

[scuby]

I do! I suppose that way I can also verify the correct function of the sensors/wiring..

Very good call. Thank you

[firstv70volvo]

I've read what seems like all the posts.

I've watched all the videos.

I've done at least 50 timing belts in my life.

I cannot for the life of me get my 2001 2.4t to not throw p00016 cam/crank position error.

Previous owner did a head gasket 20k km's ago.
Check engine been on since I bought it. He couldn't remember if it had been since the head gasket.

Runs fine.

Spent 6 hours last night trying to tackle it. My exhaust cam with the Vvt loaded up (spring type vvt) will only settle in half a tooth off. As if my timing belt won't allow the correct distance between the cogs.

I'm using a cam locking tool. The Vvt unit was replaced with the head gasket, it moves freely and looks new. I've replaced the selenoids with a known good one.

The cam marks will stay where they were set after two rotations. But like I say, always a half mark off. Is that enough to trigger the cel? Could it be something else?

Is my belt stretched due to improper install before? Seemed a bit tight but actually looks just fine. I'm grasping at straws. Anyone?

Whenever I read about these difficult timing problems I think of a person I worked with on a bent valve problem. It turned out to be the bottom timing belt pulley and stripped out splines. I don't know how often this occurs, but I've recently read about people seeing the crank pulley nut come loose or missing completely, which can't be good for the health of the pulley splines. The bent valve problem was due to completely stripped out pulley splines and I'm wondering if the difficult to time problems may be due to worn, but not completely stripped out, splines causing some movement in the pulley and a change in alignment on the crank. This is probably a long shot cause for this type of timing problem but did want to mention it as a possible problem to check out.

[abscate]

Ooof. That stripped spline things is real Volvo esoterica

Remember you can loosen the three M6 bolts and get about one tooth of movement on the cam pulley to get the teeth and belt in synch.

[scuby]

Thanks everyone

Went at it again this morning. Only had two hours.

Locked the cams. Fine tuned adjustment on the intake cam (no Vvt) it was a quarter tooth off.

The using Vida checked the exhaust cam flank angles. With the pulleys aligned properly it was reading about 40*!!!

So, I went about setting it up to achieve a correct reading. Is it possible someone installed the Vvt hub wrong? If so would it need pulling off and reinstalling?

I got to about -1 to +2 degrees. Idle was a tad choppy. Laptop ran out and I had go get the kids.

Am I right in thinking getting the angles right is the most important? If the Vvt wasn't installed properly then the mark is never going to line up either.

Tomorrow I have a few hours again and I'll double check the angle and of it still throws a code. It did today (after I adjusted the three 8mm bolts for a little more advance form -01) but my laptop died and I could only check with my phone and cheap obd reader. Might have over done it and the I had somehow unplugged the vet selenoids by accident

So tomorrow back at it with vida. Make sure the angle is within spec . If it still throws a code while being within spec, i'll be stumped.

[scuby]

Good morning

I have the exhaust cam angle fully in spec, although it goes high after clearing the code. It's correcting but not liking that is seeing about 14 degrees at startup. So it still throws a code

What worried me most is that it now idles rough. Revs up fine. Idles horribly.

Adjusting the timing any more just to get a correct cam angle doesn't seem like a smart idea as when it adjust to read between 1 & 3 degrees it still has a choppy idle (which when it's way out of range say reading 20-40 degrees) it idles smoothly.

Something has to be machanically off to my mind. The sensor is not reading the physical reality

It gives consistent information so I'm not inclined to believe the sensor is faulty.

What could cause this condition? I have checked the crank, all splines are fine and no movement there.

Interesting side note: reading the angles in vida gives good reading when the ECU has registered fault 643A, between 1-3 degrees. When I reset the code and don't touch the throttle it jumps up around the 20's

At startup/cranking it's around 30-33 for a split second until the car fires up. Then settles in the 20's then self adjust after the code appears.

I am a little lost here. As it seems the cam angle sensor and vote hub are both reading and responding to the ECM.

What could be going on here?

[abscate]

This code is a subtle one

It doesn’t set until the restart after the out of range flank angle is detected

Once it sets, flank angle is set to 20 degrees and frozen there

If it’s above 10 degrees, the code sets next time , so you have to have a process of clearing it abs resetting it each time

I think one tooth is about 16 degrees, so it needs to be right on

[scuby]

I've done a lot of timing belts. Never have I had such a pita

Redid the vvt, everything to spec. Flank angle is 30 degrees off.

I'm about to burn this thing to the ground.

[abscate]

Keep at it. I had taking the belt off and resetting it down to 8 minutes last Spring, after doing N times, N large