question about air mass readings
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question about air mass readings
I scanned my car and found two DTCs. One, a persistent but sporadic P1297 <i>(pressure drop between charger and throttle valve),</i> and a P1137 <i>(Bank 1 mixture adaptation [additive] system too rich, sporadic).</i> To fully check out the pressure drop, I need to clean the throttle body but I was wondering about the other DTC. Vacuum leak? Bad MAF? So I logged several runs this morning...
In two 2nd gear full-throttle runs, the Air mass peaked between 125g/s (1500~5500 rpm) and 138g/s (2000~5680 rpm)... and on a 3rd gear run when entering the highway, it peaked at 131g/s (at 5880 rpm).
For a non-chipped 180, I'm thinking they should peak about 145g/s. Do these airflow readings look Ok?
TIA, ~john
In two 2nd gear full-throttle runs, the Air mass peaked between 125g/s (1500~5500 rpm) and 138g/s (2000~5680 rpm)... and on a 3rd gear run when entering the highway, it peaked at 131g/s (at 5880 rpm).
For a non-chipped 180, I'm thinking they should peak about 145g/s. Do these airflow readings look Ok?
TIA, ~john
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They're low...>
Check block 32 and look at fuel adaptation numbers. Should be +/- 5%. Minus is rich correction, Positive is lean correction. A bad MAF can also show rich, though the norm is lean as they start to go. Do this key on, not running, in the driveway Engine/Measuring blocks.
On the Pressure drop, that's usually a leak. Pressure test the system..
On the Pressure drop, that's usually a leak. Pressure test the system..
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Block 32: adaptation at idle= 0.1%; adaptation at partial load= 2.3%
These were taken key on, engine off.
On a side note, over the past several weeks, I have noticed when starting her up in the morning that the engine catches with more oomph than normal, revving for a brief moment higher than it did before, as if I'd slightly tapped the accel pedal when turning the key (I don't touch the pedal). This is very brief and the idle settles back to normal within a second or two. I'm starting to wonder if this is related to the O2 bank 1 sporadic system too rich code (which was additive trim, so that would suggest at idle, right?)
On a side note, over the past several weeks, I have noticed when starting her up in the morning that the engine catches with more oomph than normal, revving for a brief moment higher than it did before, as if I'd slightly tapped the accel pedal when turning the key (I don't touch the pedal). This is very brief and the idle settles back to normal within a second or two. I'm starting to wonder if this is related to the O2 bank 1 sporadic system too rich code (which was additive trim, so that would suggest at idle, right?)
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