Contour Enthusiasts Group Archives Forums General Troubleshooting obd1 codes

I have a 95 Mystique ls v6. the CEL has been comoing on after abou 5-10 min. I went to Autozone and had them read the codes. They came up
heater control circuit
bank 1 sensor 1,
bank 1 sensor 2,
bank 2 sensor 1,
bank 2 sensor 2.
Also timing over advance bank 2 and air assitaed injector range/performance. I bought my own reader and came up with
332 insuf EGR flow/valve not opening
335 EGR sensor
173 HEGO voltage indicates rich bank 1
326 EGR pressure sensor voltage lower than
expected
538 insuf RPM change during DRT
or invalad cylinder balance test-throttle
position movement or cylinder ID problems

The guy at auto zone thought it sounded like the MAS
Should the timing be adjusted?
Do I need to replace the EGR valve and/or sensor?
Do I need to replace the O2 sensor?

I can help you with a few of those. I threw a 332 code, replaced my EGR valve... no help. I replaced the vacuum solenoid... no help. Just check everything on that and make sure it is working. I got the code to go away by putting cylander #1 at top dead center and blew carb cleaner in where the EGR valve is and blew compressed air in, all the buildup will blow out of the throttle body, make sure you have the intake off. I also threw the 172 code, O2 sensor Bank 1 LEAN, i'm going to repace it soon and it should fix it. Hope I helped.

EGR codes are commonly caused by clogged up EGR ports which can be cleaned by hand if you dont have compressed air handy. Also check for cracked or loose vacuume hoses leading to/from any of the EGR components. Once you get the intake cleaned up, reset the compuer and some of the other codes may also go away. From my experience, O2 sensors reported lean codes when they were dying.