1997 GMC Jimmy poor gas mileage

1997 GMC JIMMY
193,000 MILES • 6 CYL • 4WD • AUTOMATIC
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KEMEYER1
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  • 1 POST
our 97 jimmy has had a few problems in the last 6 months. we have changed oil & filter, put on new rotor & cap, coil & ignition control module, new plugs & wires, replaced fuel pump w/used pump, reman mass air flow sensor, replaced fuel tank vent valve & replaced catalytic convertor w/straight pipe. still not running right. sluggish coming out of the start, not much power & went though a 19 gallon tank of gas in about 175 miles. what do you think could be wrong w/it?
Mar 12, 2010 at 12:46 AM
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2CARPRO JACK
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Possibly a blown fuel pressure regulator. If you have amanual fuel pressure gauge,watch the fuel pressure to see if it drops off fast after the key is turned off.If so the reg may be blown allowing raw fuel to dump into the intake.If you dont have apressure gauge, you can try removing theupper intake plenum and looking for a "gas washed" area below the regulator. Teh reg is mounted on theside of the "spider" injector, it is around metal piece, usually with a vacuum nipple sticking out
Mar 12, 2010 at 7:37 AM