S60 2.5T misfire

[Hawgdalton]

I have an 08 S60 2.5T that started to idle rough suddenly after a road trip. Took it autozone to get codes read and it showed misfire in multiple cylinders. Their recommended fix was to replace plugs and coils. Has anyone else had this problem and was this a correct solution? How can you tell if this is not the timing belt? Thanks in advance.

[Hawgdalton]

You can find and replace only the faulty coil
Use only Bosch, maybe order 2 to have a spare one. Be sure not to drive with the misfire or at least undo the injector on that cylinder
It is indeed important to inspect the plugs, because worn ones will cause the coils to fail.

https://www.fcpeuro.com/products/volvo- ... 16#fitment
https://www.fcpeuro.com/products/volvo- ... 71#fitment
.

[Hawgdalton]

Thanks for the reply. We have not driven the car since the diagnosis. I have already ordered the parts you recommended from FCPeuro. They sell them as a complete kit for all five plugs and coils. Should be here Wednesday so I plan on replacing them all Thursday. I will update on the outcome. Is there any way to tell if this is the problem or if it's caused by the timing belt?

[MDK]

What's the odometer read?

[Hawgdalton]

145000 roughly?

[oragex]

What you can do at this point is to try unplugging each injector (it's better than unplugging the coils) and see if there's a cylinder that has no 'reaction'. It would mean that cylinder has a misfire, so then you know that was the problem.

Such misfire is usually caused by a coil. For the belt, if it breaks, the engine will shut off and won't restart.

As for the belt, it's rather easy to have a look at it without any tools, however at 145K miles if it's the original one it's long overdue. See if it has large cracks on it, if it looks smooth I would guess it was already replaced. www.youtube.com/watch?v=gS3bawaBMMk

[Hawgdalton]

Great thanks. I'll follow up with you once I work on it Thursday.

[cn90]

I do not know why people jump to ign coils so quick.

Start with simple stuff such as spark plugs first. At 145K, they are likely worn causing misfire. Replace the spark plugs and go from there.

For ign coils, I get a few used from local junk yards for $5-$10/each.

[cn90]

As above, time to worry about timing belt, water pump, serp belt etc. I wrote the DIYs in forum.

[Hawgdalton]

Thanks did not think about junk yards.