97 SSE Check Engine Light: Left Bank Lean Code Need Help!!!

[DaPhattsta]

I can't seem to figure out why the check engine light is still on in my 97 SSE. I have replaced the O2 Sensors, It has had an intake gasket, a new mass air sensor and still the light wont go away. I keep getting the same code over and over. Left Bank Lean. I am wanting to believe that its just a vacuum problem but I have no idea where to start. It sometimes idles a lil funny when you fist start it. Itll jump up and down a few times then rev up and back down. Occasionally you can also feel it idle like it has a very very small miss while sittin at a light or whereever. If anyone has had similar problems and can help I would really really apprieciate it. This light is annoyin the crap out of me.

[maxwedge]

Gotta start looking for vacuum leaks, any recent work done other than the sensors? Should also have a full scan done by a pro, looking at fuel trims, maf activity and so on. Poor injector activity also

[DaPhattsta]

The sensors is bout the only work that has been done. I have had a shop tech scan it with a snap on scanner and he keeps comin up with the same thing. He said the injectors was fine and the maf was good. The only other thing that has been done that I know of is the Intake Manifold Gasket and the Head Gasket on the Right side of the motor has been done. I don't believe the left head gasket has been replaced. To my knowledge thats the only thing that has been done.

[maxwedge]

Check the o ring seals on the pcv valve under the map sensor in the intake manifold, may have one missing, unless you are familair with this arrangement it can be hard to tell if one is missing.

[DaPhattsta]

Ill give it a shot. I am a little familiar with it. Appreciate the help

[GTP Dad]

You may want to clean the mass airflow sensor. If it is giving incorrect readings to the computer it can cause the car to run lean on one bank or the other.

[obukev]

It is possible that you have two Knock sensors on the engine. Knock sensors detect a frequency that tells the computer if there is any "ping" or "valve clatter" in the cylinder. The computer then retards the timing to adjust for that "ping". This usually happens with lower octane fuel. If that sensor is out of range, it is possible that it will set a code of too lean. The left knock sensor (if I remember correctly) is between the back of the starter and the back of the mounting bracket for the air conditioner compressor on the radiator side of the engine. The other knock sensor is between the engine block and the transmission differential on the firewall side of the engine. Anyway, it has one wire connected to it. It is no party replacing it, because the threads have a thread locker on it to keep it in place. I had to remove the starter to have room to get mine out. Also, be prepared to put the new one in its place when you get that one out.... engine coolant will come out of that hole where the knock sensor comes out.