ok, so i was having a problem with my O2 sensor and my MAF so i got new ones and it seemed to run better but i was still getting an SES. I borrowed my friends diagnostic machine w/datastream and i was throwing code 44 again. here was my O2 reading as per the ecm:

O2 fuel status: lean
O2 cross counts: 0
O2 voltage: between .00 and .09
Stayed Lean the whole time computer in open loop

MAF reading was normal and so was the TPS

now it gets interesting. I turned the car off and just turned the ignition on and all of the sudden the diagnostic machine comes up incoming code. the car wasn't even running, so i see what it is and its Code 33 MAF malfunction out of the blue, so i start her up and after code 33 came on the ECM stays in closed loop now and now i have normal O2 sensor readings and they are as follows:

O2 fuel status: Flips Rich and Lean as it should
O2 cross counts: 18-30
O2 Voltage: beatween .24 and .89

I am completely flabergasted and i have no idea whats going on. i checked the MAF burnoff relay and i noticed that the black wire is falling out of the harness but i shoved it back in there. I didn't look at the MAF power relay. I'm extremely frustrated and need some help



dont know if this helps but with the ignition on car off in datastream the computer gives me a MAF reading of 3460 g/s and then i start it it goes down to about 2100 g/s.....shouldnt it read zero when the engine is off?...i also unpluged the MAF power relay and i had no change in my readings....i figure if i pulled the power relay that i would get a 0 reading but i didnt it was exactly the same


put the old MAF back in, and an idle figure around 1900 gm/s for the MAF, but i threw a code 33 and a 44 again, from what i read on another post code 33 should only set when this occurs:

4500gm/s or more for .06 seconds with TPS less than 1/4 throttle, RPM under 2000

Im starting to lean towards either a bad hypertech chip, or a bad ECM

 

ok i think im making a little headway, i can make the MAF code 33 appear almost on command. so what i did was i reset the computer, and then purposely set code 33 on purpose (to do this i just turned the ignition on and let it sit for about 10 seconds like that and it triggers the code and gives me a very generic g/s reading, i guess what it should be roughly) when codee 33 is active my o2 sensor reads spot on and my rich condition in gone and i won't set 44. my question is with code 33 active will the ecm put out a standard o2 reading as well as a standard g/s MAF reading? or are those the correct readings and i have either a bad MAF or a bad wire somewheres?

 

When code 33 is present the ECM will ignore the MAF and create an airflow value. The ECM uses the RPM and throttle position to create this airflow value (an N-Alpha mode). The calibration of this value is decent enough that the engine will run rather well.

When the ECM is actually using the MAF the engine runs rich. Which makes sense as code 33 is a MAF high error.

I'd say that the MAF is either bad or there is a wiring issue. Also check the connector where it plugs into the MAF.

RBob.

 

so the ECM is reading the correct O2 sensor readings then? i figured that it was ignoring the MAF readings because the reading it was giving me was way to constant. I have a brand new MAF on order it should be here tomorrow, so we will see if that does the trick, if not i'll have to tear into the harness not looking forward to that