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failed smog


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I recently had my 84 cutlass supreme 3.8L V6 smogged and it failed miserably. The HC and CO were extrememly high, high enough to get the car labeled a GROSS POLLUTER. Now, I replaced the spark plugs, ignition wires, air filter, PCV, and crankcase breather. What would cause such high emmissions?<BR>Please help.<P>rene<BR>mrbboy@netzero.net

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Is your "check engine" warning light on? If it is, one or more sensors or devices has failed and set a trouble code in the computer. Some that come to mind are: oxygen sensor, coolant temp sensor, idle speed motor, mass airflow sensor... any of these could fool the computer into thinking the engine isn't warmed up and cause it to stay in open loop mode- meaning the engine will run, and probably run ok, just not at its peak efficiency. This will cause the high smog readings.<P>And then again, it could be faulty test equipment. I've heard the things are programmed to fail a certain random percentage of cars tested, though the mfg and the state will deny it to high heaven.

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There was an electrical plug that I forgot to connect on the carb that caused the "check engine light" to come on, but after I plugged that one back on, the CEL turned off. Is the fuel mix adjustable on the 2 bbl carb for this car. What ablut the idle?<P>Rene

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I know nothing of a 84 Cutlass or the earlier carburated 3.8. Sometimes a good diagnostic man may be able to get to the bottom of it in far less time than oneself. So sometimes this may be the best option. Ive seen alot of people "throw" alot of parts at an engine just to find out it was only one. Your computor is probably sending a rich fuel mixture, like the car is cold. A warn timing chain and gear can throw things off also and changing these is recomended on the later FWD 3.8's anytime around 100,000 miles. But that is a different engine. Sorry I cant help more. Id find a good diagnostic man.

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You might try disconnecting the battery for 5 minutes, reconnecting and smogging again. The engine may have been running in default mode since something was disconnected. <P>If that doesn't work, can you hear a clicking sound in the carb when you first key on without starting the engine. If not, the MCS (mixture control solenoid) might not be working. If it ain't working, you ain't gonna pass a sniffer test!<P>Mike

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