ROB ROY

MY 94 IMPREZA WAGON IS STILL HESITATING AT FULL THROTTLE, UNTILL IT HITS 5000 RPM THEN IT SITS UP AND BEGS. IF I DRIVE IT HARD FOR ABOUT 15 MINS IT EVENTUALLY CLEARS ITSELF AND ITS FINE FOR A COUPLE OF DAYS, THEN IT GOES BACK TO NORMAL. I RUN IT ON SHELL OPTMAX WITH NF OCTANE BOOSTER AS ITS AN IMPORT. I`VE HAD A MAJOR SERVICE DONE, AND IT WAS FINE FOR A WEEK OR SO THEN WENT BACK TO ITS USUAL TRICKS. I`VE SINCE CHANGED THE FUEL FILTER AGAIN AND CHECKED THE INTERCOOLER HOSES AS SUGGESTED ON THIS BOARD,BUT STILL THE SAME.
I`D BE GRATEFULL FOR ANY SUGGESTIONS.

CHEERS ROB ROY.

scoobyslut

Are you running a standard paper air filter? if not, try changing to one, as the maf sensor might be picking up oil off the filter element [if that type], other than tht, try swapping the maf sensor with someone, may be the cause.

ktomass

MAf sensor could be the cause but on this MY they were lasting for ages. I would suggest that you check lambda sensor. This was cause for hesitation on my Legacy MY92.

Kristijan