why suddenly high fuel consumption on 93 G20?

[chuckm]

I need better advice than is available hereabouts. My beloved 93.5 G20 suddenly began delivering ca. 20% poorer fuel mileage about a month ago. Oddly, there's no appreciable change in running/performance...just disturbingly bad consumption figures. If I could find a fuel leak, that'd explain it just fine--but no luck there. Have checked plugs/ignition in general, injector firing, timing, vacuum line health, wiring to MAF, TPS, etc., all OK. Also, no 'check engine' light flashing. I'd be very grateful for any help or tips.chuckm in KY

[nametakennow]

Have you checked the coolant and intake temp sensors?

[chuckm]

Thanks for responding. No, haven't checked temp sensors yet--a good reminder. Today, tho, I tackled the PAIR solenoid, since I had to replace the PAIR valve awhile back. Solenoid does function when tested separately. But...can't tell if it's switching when reconnected. I also don't seem to be getting any vacuum to the EGR when goosing throttle. There's another solenoid buried beneath the throttle body (that I really can't get my hands on, dammit). I'm wondering: if the EGR solenoid is nonfunctional, does that affect operation of PAIR solenoid as well? And...if both are out of commission, might this cause bad fuel mileage? Thanks again.chuckm