Z28 runnin 2 rich$$$$$
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Joined: Jun 2007
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Z28 runnin 2 rich$$$$$
my 94 camaro z28 is starting 2 run rich (u can smell gas) sometimes and starts to hesitante and idle high could this b the problem of a bad fuel filler and/or oxygen sensor. I start 2 see problems when i start racing. Also if it is the oxygen sensor is my before or after the cat.
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Is your 94 stock or modified? Does it have the stock exhaust?
Your 94 has two O2 sensors, both before the cat. If you have a stock exhaust system, one is in the drivers side exhaust manifold, at the very bottom, the other is in the passenger side branch of the Y-pipe, below the exhaust manifold.
A plugged fuel filter may cause a misfire under heavy engine load, but a plugged filter will make it run lean, not rich. Typically, a rich condition is caused by a "false" lean reading on the O2 sensors. Could be faulty sensors, exhaust leaks before the O2 sensors or misfires. A data log, using a software scanning system will generally tell you if you have a false lean condition, by looking at the long term fuel corrections (BLM's).
O2 sensor problems or a dirty fuel filter will not cause a high idle.
Your 94 has two O2 sensors, both before the cat. If you have a stock exhaust system, one is in the drivers side exhaust manifold, at the very bottom, the other is in the passenger side branch of the Y-pipe, below the exhaust manifold.
A plugged fuel filter may cause a misfire under heavy engine load, but a plugged filter will make it run lean, not rich. Typically, a rich condition is caused by a "false" lean reading on the O2 sensors. Could be faulty sensors, exhaust leaks before the O2 sensors or misfires. A data log, using a software scanning system will generally tell you if you have a false lean condition, by looking at the long term fuel corrections (BLM's).
O2 sensor problems or a dirty fuel filter will not cause a high idle.
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Joined: Sep 2007
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Hi guys im new to posting in this forum so, Hello to all Camaro Fanatics! 
While you guys were on the subject. My camaro runs rich with a strong gas smell. The car has 113000 miles and im guessing the o2's are stock. Should I wait for a code to be thrown before replacement? or should I just swap them out. Just did a fresh tune a month ago. New ICM, and Coil, Plugs, Wires. New Gm Opti replaced at 80000 miles. EGR threw codes before the MadZ tune? Any help would be awesome!!
While you guys were on the subject. My camaro runs rich with a strong gas smell. The car has 113000 miles and im guessing the o2's are stock. Should I wait for a code to be thrown before replacement? or should I just swap them out. Just did a fresh tune a month ago. New ICM, and Coil, Plugs, Wires. New Gm Opti replaced at 80000 miles. EGR threw codes before the MadZ tune? Any help would be awesome!!
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