help! thermostat replaced, engine light still on, drive cycles?

2002 VOLKSWAGEN JETTA
113,000 MILES
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LIZ1111
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I need to get the vehicle certified for registration and it failed the smog emissions test.

So, my mechanic just replaced the thermostat and now I have a gauge that works, (also my heater works again!)


However, the engine light is still on. Will this go off by itself? How many drive cycles will it take to get eveything ready for the emissions test?

Thanks in advance. Farvehgnugen!
Feb 10, 2012 at 6:18 PM
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JACOBANDNICKOLAS
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The thermostat will not turn the engine light on unless it overheats. Have the computer scanned to identify trouble codes.
Most parts stores will scan it for free.
Feb 10, 2012 at 7:12 PM
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LIZ1111
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thanks. Do you know anything about the engine cycles to reset the other things that need to be reset in order to pass the smog emissions? There are 4 that need to be 'ready' and after the mechanic visit, I only had 1 'ready'.
Feb 10, 2012 at 7:15 PM
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F4I_GUY
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Replace the ECT if the sensor body is all black. That is why your engine light is on and is not turning off. There is an updated green sensor.

After replacing it, clear the fault. I don't know why you're waiting for it to shut off? Go to auto zone, they'll clear it for free.
Feb 14, 2012 at 4:02 PM
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EXOVCDS
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Clearing alone will not get him passed smog. Like he said, the 4 readiness monitors that are "checked" need to pass readiness by the ECM first. Readiness setting can be performed by following a procedure... what engine size?

@ Jacobandnickolas, a faulty thermostat WILL set a "Cooling System Performance Malfunction Code".
Feb 18, 2012 at 9:57 PM
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