Emissions test tune-up
Meridivs
02-09-2010, 05:30 AM
It's time for the periodic emission-test for my '92 Pontiac Trans Sport.
The engine is a 3.1 TBI V6 and it's idling a little rough. Acceleration and idling with AC ON is fine but idling with no load is not ok.
I have done so far:
- plugs & spark wires
- new air filter
- new distributor cap and rotor
- new Ignition Control Module
- cleaned-up EGR
- new PCV valve
- new thermostat (I don't know if it's related)
- new injectors
The car was idling this way since I got it and nothing I did changed anything. Except turning on the AC which increases the engine idle speed at ~1000rpm, then it idles fine.
Do you have an idea what else I can do to improve my emissions (they check it here at idle rpm)?
Any advice, things I might look into are very much appreciated!
The engine is a 3.1 TBI V6 and it's idling a little rough. Acceleration and idling with AC ON is fine but idling with no load is not ok.
I have done so far:
- plugs & spark wires
- new air filter
- new distributor cap and rotor
- new Ignition Control Module
- cleaned-up EGR
- new PCV valve
- new thermostat (I don't know if it's related)
- new injectors
The car was idling this way since I got it and nothing I did changed anything. Except turning on the AC which increases the engine idle speed at ~1000rpm, then it idles fine.
Do you have an idea what else I can do to improve my emissions (they check it here at idle rpm)?
Any advice, things I might look into are very much appreciated!
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