1998 Pontiac Bonneville missfire?

1998 PONTIAC BONNEVILLE
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GRAHMH
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Engine Mechanical problem
1998 Pontiac Bonneville 6 cyl Front Wheel Drive 120000 miles

the car will barely idle and sounds like a missfire. but i checked the coil pack, plugs, wires, modue, and air filter it smells like eggs when u rev it and it shakes but i can get the rpms up 3.5 but dont want to see if i can get it higher
Apr 30, 2010 at 2:19 PM
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INTERNETMECHANIC
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How long since a tune-up? Are there any trouble codes? If you want to check generic codes, yourself, at the least, you need an obd2 code reader. Some of the national brand autostores used to check generic codes for free, you can call and ask.

Use a gage and check fuel pressure. Some systems you can use a dmm to take inductive reading from spark plug wires and compare, engine running. It's an inductive reading, you don't penetrate the spark plug wire insulation or take the wire loose, just touch it. It's not conclusive, but, it is fast and non-invasive. Say four readings from four different plug wires show around 1/2 volt, the actual reading doesn't matter,but, they should be close to the same. Then two plug wires on the same coil read zero, I know where to start looking. Of course, it may not be a spark issue?

Maybe there is an idle air problem?
Apr 30, 2010 at 3:21 PM
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