umoms

I have a 2003 Chevy Cavalier with 90,000.00 miles and I get the following codes p0171 p0340 p1133 When i put the car in drive the entire car shakes.... What could be the issue

I know P0171 System too Lean (Bank 1)
P0340 - Camshaft Position Sensor 'A' Circuit Malfunction
p1333 HO2S-11 (Bank 1 Sensor 1) Insufficient Switching

Could the oxygen sensor be causing all these codes?
I notice this vehicle does not have a camshaft position sensor but i get the code for it.

Any ideas?

EinST

The PCM cannot manage the fuel with missing or irregular CMP sensor input. On the L61 Ecotec the ICM synthesizes the CAMOUT signal from the way the spark plugs fire and thus the culprit is probably one or more of the ICM, ignition coils, and spark plugs. Fix P0340 and I think P0171 and P1133 will go away.

umoms

I replaced the ignition control module and its still doing the same thing. Although I am only getting code P0171

Whenever I drive and come to a stop (idling) the RPMs will move from the .5 to 1 back and forth and the engine would shake.

Also is it true this vehicle does not have a Mass Air Flow sensor?

Could it be the O2 sensor? If so which one? The front?

EinST

There's no MAF since the air flow can be modeled from other parameters, so they thought. Did you happen to pull the plugs? What's the history with this vehicle?

umoms

gave it a full tune up 4 months ago

EinST

I was asking if you had pulled the plugs and inspected them. Replaced the spark plugs "4 months ago," then but with what? The wasted spark ignition on the L61 doesn't like fancy/exotic spark plug configurations. It's best to use the correct ACDelco plugs for the application.

umoms

yep AC Delco...Clean the spark plugs up...All look an test good

EinST

Okay, then. The PCM constantly adjusts the short term fuel trim (more or less than the programmed norm) based on the upstream O2 sensor once in the closed loop. It then figures the long term fuel trim by keeping track of the short term fuel trim values. When the long term fuel trim exceeds some value (~23%, i.e., it had to add that much fuel), it sets P0171. So, the O2 sensor is out of calibration (any exhaust leak around the sensor?), the MAP sensor is out of calibration, fuel injectors are clogged up, or the fuel pressure is low, perhaps. Just for giggles, post the freeze frame data and see if anything jumps out?

umoms

Turns out it was the Upstream o2 sensor. I pulled it out and it was full of carbon so I replaced it and instantly idles like a champ.

Thanks everyone.

Shadow22

Was it the sensor in the manifold or the next one?