2006 XC90 2.5T timing advice Topic is solved

[Aberration]

Hi all, I'm the FNG. I searched a few hundred entries prior to making this post, so as not to be redundant, but have some questions.

Helping a friend with an '06 XC90 AWD 2.5T. Haven't really worked on these before; have had my head buried under mostly American and Japanese cars...bit of German. The Swedes do it a little differently, which has had me stumped.

So, in all, timing belt, water pump, radiator (with upper and lower hoses), and power steering pressure line all needed to be replaced.

I looked at every resource I could find after initially realizing the engine isn't timed by TDC. What I did do, however, was release the 8mm bolts on the cam pulleys relative to the hub (they'd been loosened before, for another timing belt replacement years ago). The engine starts, has a horrible idle (misfires) and is reporting P0300, and P0301, along with another cylinder that seems to be moving when a coil is swapped. I had pulled Cyl. 1 spark plug, which is consistently giving issues. The spark plugs were replaced last year, with new boots. I suspect that either the gasket isn't seating properly from re-use, or the ceramic may have inadvertently cracked when taking out the plug (it happens, and I'm not surprised if that's the case). Hopefully Cyl. 1 isn't damaged (my primary concern).

How I approached the timing belt, and where I really need advise: should I treat it as a hub replacement, loosen everything, and then retorque?

I changed the belt, noticed the cam lock slots did not line up at all, though the pulley marks did. Both intake and exhaust were considerably off, even after the whole forward/reversing of the crank to unload the hubs.
I wound up locking the cams, setting the timing marks on the pulleys (both were loose from the hubs), but did not loosen the hubs from the cams.
Next came rotating the hubs fully counter-clockwise in the pulleys, and snugging two bolts each down. I then replaced the timing belt, working counter-clockwise, keeping tension, and keeping the pulleys with timing marks matching the cover, then tensioned the belt accordingly (given the temps, aiming for middle of the tension).
After that was done (the cams were still locked, and pulleys ), I then loosened the 8mm bolts, and adjusted the VVT hubs as far clockwise as they would move in the pulleys, and both came to a stop just short of the full travel of the bolt slots.
I then tightened down the 8mm bolts (all 6) and unlocked the cams, then spun the engine by hand a few revolutions. Everything lined up on the pulleys, cam slots, and crank. I didn't feel any odd resistance other than some resistance from compression, but no hard stops or noises.

In doing this method, did I foul something up? The pulley is not located on the same spot of the hub as it was when I first saw it, but the marks align to the 2nd (older) set of marks. The engine starts up quickly, but the misfire is considerable and consistent, though the engine idles in the 640-670 RPM range pretty steadily. Only the P0300/P0301/P030whatever cylinder received the questionable coil remain, though the engine has not been up to operating temp yet due to the loping idle. I do not have a Volvo specific scanner, hence the generic OBD-II codes.

I plan to re-check the timing in the morning and probably grab another spark plug, maybe a coil, though I suspect the boot may be an issue. Any advice would be welcome. Even if the timing marks align when checking, is it wise to just loosen everything and treat it like a VVT hub replacement/alignment?

If this really is a duplicate and I somehow missed it in the search, apologies. Thanks for any help provided (in searching, some links were very helpful with .PDFs and better info that I'd previously found - thank you).

[Aberration]

UPDATE:

So, everything checked out to still be in time as I'd set it. Replaced a plug and boot; all runs perfectly normal. Wasn't a bad coil, just a missing spring connector. Definitely smoother running now than when my friend brought it over.

Side note: I don't envy anyone who's had to replace the power steering lines on their cars. Arguably one of the worst parts I've had to replace, however, it's all fixed, and that monkey is off my back.

[Aberration]

Another update:

Friend contacted me again today saying the engine is stumbling, a little at idle, sometimes normal driving. I can't replicate it, but am suspecting the ignition system. This is a stubborn vehicle, and now I'm debating on buying a DICE scanner for the volvo specific codes, or to see if, somehow, the new timing belt is somehow not lined up, but the engine runs really smoothly.