97 GSR I recently picked up.

Consistently getting 19-21 mpg, with a mix of city / highway (predominately highway) driving.

Things I've done -

Checked air filter - looks new
Replaced plugs - didn't look too bad, but #2 was a little white
Replaced fuel filter - last night. Not sure if this will make a difference or not

New symptom to add -

Sometimes (it's happened 4-5 times) when I hit between 4-5k while slowely accelerating (not floored, but giving it some) it has what feels like a hole in the fuel map.

I doubt it's a misfire since it's fine at all other RPMs.

I'm thinking the VTEC solenoid is sticking. Would that throw a CEL?

 

check the ignition timing. the low mpg here is what's making me think elsewhere. a vtec solenoid oddly won't always throw a cel when it fails. the thing is, your mpg statements point somewhere else. out of vtec you should be getting around 300 miles per tank with a stock gsr