1999 Buick Lesabre po172 system too rich

1999 BUICK LESABRE
172,000 MILES • 6 CYL • FWD • AUTOMATIC
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SJDEMURE
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Took car to auto repair place, said that my O2 sensor was bad. had that replaced, cost me $150 bucks. but Check engine light comes back on after a few miles driven. Went to Autozone, they game me a free computer scan. Said the code was PO172 system too rich ( Bank 1). Store attendant said that my engine might be getting too much fuel. But car is slow to accelerate as soon as I put my foot on it. I could be at a red light, fullly stopped, then once I step lightly on the accelerator,I get a very delayed acceleration. I need some suggestions here. i dont want to go broke trying to figure this out.
Jun 10, 2008 at 8:36 PM
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RASMATAZ
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Possible causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode
Jun 11, 2008 at 12:31 AM
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SJDEMURE
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could the problem also be an intake manifold gasket problem?
Jun 11, 2008 at 12:39 AM
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RASMATAZ
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Intake gasket leak will lean the mixture and the computer will throw fuel at it to compensate-You can check for leak with WD40 and spray between the intake manifold flanges when it hits the leak area the idle will smooth out-

You need to check the items I've mentioned earlier.
Jun 11, 2008 at 4:06 AM