1999 Chevy Tahoe

1999 CHEVROLET TAHOE
146,000 MILES • V8 • 4WD • MANUAL
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JBEHUNIN
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  • 1 POST
I have a 1999 Chevy Tahoe with about 146,000 miles on it. The check engine light keeps coming on, and when I take it to a mechanic, it always reads a message code of a cylinder 5 misfire. I put on new plugs, wires, cap and rotor in it, and the check engine light went off, but it runs worse than it did before.
I rechecked all the caps and all were on tight. The truck runs great when you punch the throttle, but boggs when you drive it normal. The check engine light came on again, this time it read rear catalyst below threshold bank 2. I put in new o2 sensors just a month or two ago.
Is this the catalytic converter?
Nov 28, 2008 at 6:45 PM
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PEAR69
  • CAR REPAIR CONTRIBUTOR
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First, what brand, plugs-wires-cap-rotor, did you install?
It probably is not the converters. It sounds like a fuel delivery problem. It is common for the fuel pressure regulator to go bad on these engines. It also could be the throttle position sensor (TPS). Test this sensor.
It is also common for these engines to develop lower intake manifold gasket failures. Check for intake leaks. Was this gasket ever changed?
It is also common for these engines to develop failing grounds. Check every engine ground for corrosion or burnt wires. Especialy the one that connects to the intake water neck (the upper radiator hose connects to the water neck)>
Nov 28, 2008 at 7:04 PM
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