1999 S70 T5 Timing belt tensioner question

[kmg108]

Hey there folks.

I don't post often, because I can usually answer my questions with the search feature; however, I need some insight from the pros on this one.

My car has been periodically throwing the P0014 code for exhaust cam being over-advanced. I generally ignore the light because it comes and goes as it pleases, and the car runs great with the light on or off. I just finished installing all new engine mounts and thought I might look into the cause of this CEL while I am working on it. I first pulled the solenoid on top of the head. I cleaned it out well and didn't see any gunk buildup (I run synthetic). I also hooked it to a 12v source and verified the solenoid is clicking as it should. I put an ohm meter on it and it had a nice low ohm reading...which I suspect is probably accurate. I reinstalled the part and moved on to other areas of the timing setup.

I pulled the right front wheel and got the timing marks to TDC. All the marks lined up as they should, so I don't think the timing is off. Something that I did notice, though, is the timing belt tensioner needle. It was a nice cool engine, and the needle was right in the center of the two marks. I grabbed the tensioner with my hand and noticed that I can physically move the needle with my finger to make the belt really tight or loose. I understand the concept of the eccentric tensioner, but here is my question: Is it normal that the tensioner needle can be moved forward or backward my hand when the center bolt is fully tightened? It seemed odd to me that I could move it so easily...and wondered if that might be what is causing my CEL to come on.

Any thoughts? Thanks in advance. I really appreciate the knowledge and willingness to help a fellow wrencher on these forums.

[precopster]

It's a spring loaded tensioner and what you describe is normal.

In fact that's how you can remove the belt easily by hand by also loosening the 12mm bolt and turning the 5mm allen hole to a looser position.

Are you 100% certain in the timing mark positions? One tooth off on the crank will give a P0014.

[kmg108]

Thanks for the reply. I did some additional searching, and noted that the following link also verifies that the needle should have movement. Here is the link that confirms that:

http://volvospeed.com/volvo_repairs_how ... tment.html

As for the timing marks, I'm fairly certain they are accurate...but I will check again since it is still apart. I can visually see that both camshaft markings are perfectly aligned with the marks in the plastic timing belt cover. The part that has me still curious, is the crank mark. I have not been able to locate the mark on the crank as of yet. I spun the engine by hand many revolutions but never seem to find the mark. Is the TDC crank mark located on the crank-mounted serpentine pulley, or do I need to remove that pulley in order to see the crank pulley mark on the toothed pulley?

[precopster]

So cams are aligned with cover however if you haven't positively identified the crank mark there's the issue.

There is a raised bump on the crank pulley that lines up with the crank marks. This can be used instead of the small notch(es)

[kmg108]

Here are my timing marks. They were hard to get a good angle for the pics. I determined that the toothed crank pulley actually had a small notch on the back of two teeth that were side by side. I noted the "bump" on the engine cover and attempted to use a white pen to touch all the timing marks for easier viewing. Please look at the below setup and tell me if the car appears out of time to you. My opinion is that it is good. There does not appear to be a tooth in one way or the other that would be better in terms of lining up these marks, in my opinion.

[kmg108]

based on the above photos, I'm leaning towards an oil pressure problem that is not allowing adequate flow to the solenoid on top of the head. I will change oil and filter with good grade oil to see if that helps with the CEL at all.

[Ozark Lee]

From the second picture it looks like the bolt through the slot on the CVVT sprocket is very close to being maxed out in the travel. That is typically due to the preload not being set correctly but I didn't see that you have recently changed a timing belt. The P0014 is also typical of a preload problem.

When the proload is properly set the bolts that hold the sprocket onto the CVVT hub should not be at either end of the range in the slot but it won't necessarily be centered either. You might want to go through a preload setting procedure and see if things settle down for you.

To set the preload crank the engine clockwise to the timing marks and then continue clockwise another 90 degrees. Reverse the rotation and bring the marks back to the timing marks going counterclockwise. Loosen the tensioner, remove the timing belt from the camshaft sprockets, and then thread it back on. Keep the belt very taught as you go onto the intake camshaft sprocket and then turn the sprocket for the exhaust cam to line up with the timing mark as the belt goes across that sprocket. Reset the tensioner and give the engine another couple revolutions cranking by hand and recheck your marks. At this point you will likely need to touch up the tensioner to get the indicator centered in the window again. Torque down the tensioner bolt and crank it up. You may need to fiddle with the tensioner settings a couple of times to get it back normalized to be within the window but it should stay there.

...Lee

[precopster]

The bump: be sure the white-out marks are actually identifying the 2 notches:

Also using the bump on the crank pulley is also fine.

[kmg108]

I figured I would write a follow-up note. I purchased the cam shaft locking tools and got the camshafts locked into the correct position for TDC. I then removed the timing belt and rotated the VVT hub all the way to the clockwise position before reinstalling the timing belt. I also changed the oil/filter and swapped out the cam solenoid gasket to the newer screened version (along with cleaning the solenoid).

I've put a few hundred miles on it and the light has not come back on since. I think the problem is now fixed. Thanks for the suggestions.