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Old 07-01-2006, 08:43 PM   #9
deliriousga
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Join Date: Jun 2005
Location: USA!!
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Quote:
Originally Posted by insite
disconnect your battery for a few minutes and go for a cruise ('till the MIL comes on). then post your long term and short term fuel trims and your O2 readings (if you have a scanner)
I disconnected the battery, reconnected and took her for a 40 mile drive to the dealer to get some screws today while having the OBDII scanner record everything on my laptop. Here's what was recorded:

Long Term Fuel Trim: -0.8% on both banks, never changed under any load.

Under Higher Load
Short Term Fuel Trim: On the highest load (68.2%, 4675rpm@91mph) the short term fuel trim was -1.6% on bank 1 and -3.1% on bank 2. The breakdown was 0% bank 1, sensor 1, 99.2% bank 1, sensor 2, -3.9% bank 2, sensor 1, 99.2% bank 2, sensor 2.
O2 Sensors: Bank 1, sensor 1 795mV, bank 1 sensor 2 820mV, bank 2 sensor 1 790mV, bank 2 sensor 2 830mV.
Timing Advance: 22.5 degrees.

At Idle with rough idle & MAF plugged in
Short Term Fuel Trim: On idle load (6.7%, 896rpm) 0% on both banks. The breakdown was 0% on banks 1&2, sensor 1 and 99.2% on banks 1&2, sensor 2
O2 Sensors: Bank 2, sensor 1 45mV, bank 1 sensor 2 60mV, bank 2 sensor 1 170mV, bank 2 sensor 2 35mV.
Timing Advance: -8.5 degrees.

I have several other readings if they will help. I ordered new O2 sensors since I have 82K on the clock and they should last about 60K miles. It seems like with the MAF plugged in the flow rate is very high at idle (1.5 lb/min @ 896rpm) compared with the normal idle (.657 lb/min @ 697rpm).

Any other ideas of what to check besides O2 sensors?

TIA!
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