Volvo C70 misfiring after refuel

[Awan]

Hi all,
After petrol reserve light came on; I filled in about 15 litres of Vortex95. However in less than quarter of a mile; the car started misfiring. I drove for about 30 miles and then filled up the tank to full with Shell V-power98. However the issue didn't reaolved.
Engine checklight with following codes appeared. ECM-3503 and ECM-3513 (Misfire in Cylinder 1)
So went to local mechanic and he said engine misfire is due to ignition coils. And that I also should change spark plugs.
As Coils are expensive here I just changed plugs with Genuine Volvo spark plugs but the issue didn't resolved.
I cleared codes and now codes are showing misfire in cylinder 2. ECM-3523. Cleared codes again and still misfire in cylinder 2. Mechanic says if fuel had been an issue; misfire would be random in different cylinders.
So I am thinking of ordering coils from FCPeuro, IPDUSA etc. But what is bothering me is what if the issue is beacuse of bad fuel/gas. As it occured right after refill. How can I check whether water etc. in fuel is causing it or problem is from coils.
Thank you for your time.

[wizechatmgr]

Try swapping coil #4 and coil #2. See if the problem immediately follows the coil. If so, time to replace it.

[rspi]