So I bought a 2004 Volvo xc90 t6 AWD 2.9L straight 6 and it's a fixer upper so I need to order coil packs and plugs . So I'm shopping n looking n I keep coming across the choice if my vehicle is this VIN 91 or not. So I've tried vin number searches and what a waste of time n a couple bucks. So I'm hung up on this VIN 91 because I'm scared I'll order parts that won't be correct. So can anyone tell me something on this please.
oh vin is YV1CM91H841047510

 

buried in the VIN is a two digit engine code. You can also find the engine code under the hood (look for a sticker on the timing cover). look for something like B6294T (where B = gas, 6 cylinder, 2.9 L displacement, T = first gen turbo. I looked at the Volvo Modular Engine WIKI and don't see any T6 variants so you should be ok to order on that engine description alone.

When in doubt, you can shop a Volvo friendly web store like FCP Euro, IPD USA or EEuroparts, or you can shop a dealer web store - I use Tasca Parts here in the northeast but there are plenty of others. Try searching a dealer store to find the genuine Volvo part numbers then you can compare those to other sites. PS - curious why you want to replace the coil packs. Are you doing so just because they are old or are you getting misfire codes? As to plugs, I'd probably stick to OEM and make sure you know what the factory gap is. Older engines don't necessarily run better with the more expensive plugs.