Both. If the filter is easy to replace, consider:
1. buying 3 filters
2. replace the filter now
3. drive home trying to get home with as little fuel in the tank as you dare
4. drain the tank. This step can be skipped if the filter changed in step 2 looked clean.
5. refill the tank and change the filter again
6. if the filter again shows clean. Water was most likely the problem.
7. keep the 3rd filter, onboard, as a spare
I've has some bad fillups (with gas coaches not my signature coach). I never drained the tank because the filters looked clean.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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