Engine Performance problem
2002 Saturn SC1 4 cyl Automatic 110000 miles
I have a 2002 Saturn SC1 and the " service engine soon" light is on and I recently took it to get my emissions test done and they told me that my car's idle is to high and they couldn't perfom the test. Now I never really noticed until they brought it to my attention, but in park it is idleing at 1500 - 1700 rpm and if I keep pressing the brake while I'm in park then the rpm will keep going up with every press of the brake and drop back down to 1500-1700rpm once I stop. When I shift into drive then the rpm will drop back down to 800-900rpm. Somebody had mentioned that it may be the 02 sensor as I don't think it has ever been replaced. Any help would be appreciated. Thanks
U said that the service light is on what codes do u have?Also check that hose that runs from the valve cover to the intake manifold that short little s shaped one see if it's got a hole in it or colasped when it's running. Also that model gets intake gasket leaks causing vaccuum leaks and high idle and missing. Look on the passenger side of where the intake meets the head around the first too cyclinders see if the intake gasket looks wrinkled up.U can also let it idle and spray carb spray any where u think u may have a vaccuum leak if the rpms go up or it run rough or dies u have a leak there. Let me know what u find.
February, 14, 2010 AT 12:20 PM
Thanks for your fast response, I will try what you said and let you know what I find.
February, 16, 2010 AT 7:42 PM
Take hose off that connects to engine air filter and throttle body clean the plate in the throttle body if it has carbon build up.
February, 16, 2010 AT 9:36 PM
These are the codes I got when I hooked up the computer.
PO340 - No Camshaft Position Sensor signal at powertrain control module.
PO301 - Cylinder 1 Misfire Detected
PO341 - Camshaft Pos Sensor Circuit
PO128 - Thermostat Rationality Error Detected
PO507 - Idle Control System, RPM Higher than expected
I'm not sure if all these codes are in reference to the current problem, or if some are old codes that hadn't been cleared previously but that's all of them. Hope this helps with the diagnosis.