Car runs rich after battery is recharged.
I thought the only way to reset the fuel trims on the 8 ecu was to disconnect the battery as they wont reset with a flash like the 9 ecu.
Then you have to do the drive cycle to allow the ecu to re-learn and get the trims right.
I guess it could be rich while doing this but not to the point of going from 14.7 to 12.0 afr
Then you have to do the drive cycle to allow the ecu to re-learn and get the trims right.
I guess it could be rich while doing this but not to the point of going from 14.7 to 12.0 afr
Check if your 02 sensor is plugged in and working. if the ECU doesn't see the 02 voltage it will max out the short term fuel trim to 25% very quickly. You should get a CEL pretty soon though if this is the case.
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thanks for the feedback everyone, I really appreciated, anything else please contribute thanks!
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evo 8 fuel trims don't reset with a battery disconnect.
the injectors are not on a voltage regulated circuit. if battery voltage drops during engine operation, then injectors latency increases. there's a table in the ecu code that stores the inj latency as a function of battery voltage. if those values are not accurate, afrs will fluctuate. the biggest fluctuations will be at idle and cruise where inj latency is a big fraction of the total pulse width.
the injectors are not on a voltage regulated circuit. if battery voltage drops during engine operation, then injectors latency increases. there's a table in the ecu code that stores the inj latency as a function of battery voltage. if those values are not accurate, afrs will fluctuate. the biggest fluctuations will be at idle and cruise where inj latency is a big fraction of the total pulse width.
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lol. That's a little too low! I don't think the car will actually run at 1.5 volts. Hook up a volt meter across the battery terminals, tape the meter to your windshield, and report back what values you get before and after starting the car. Watch it for a few minutes before shutting it off.
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lol. That's a little too low! I don't think the car will actually run at 1.5 volts. Hook up a volt meter across the battery terminals, tape the meter to your windshield, and report back what values you get before and after starting the car. Watch it for a few minutes before shutting it off.
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lol. That's a little too low! I don't think the car will actually run at 1.5 volts. Hook up a volt meter across the battery terminals, tape the meter to your windshield, and report back what values you get before and after starting the car. Watch it for a few minutes before shutting it off.
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