MAP params - Default MAP offset - A/C on?

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Dave001
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MAP params - Default MAP offset - A/C on?

Post by Dave001 »

Would I be correct in assuming this enriches the tune when the A/C is on?

I've got an Ecotec running on an 082 ecu with 12P, and it runs lean when you first turn the A/C on.

Thanks,
Dave
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vlad01
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Re: MAP params - Default MAP offset - A/C on?

Post by vlad01 »

Pretty sure default MAP means a pre-programed fail safe values for when the MAP sensor fails so you can still drive the car with AC if the MAP fails.

If this is correct, it would be an approx value to offset in the event there is no MAP input so that the engine doesn't just die if the AC were happen to be used in a failed MAP situation.

I am sure someone can confirm is this is right or wrong.
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Re: MAP params - Default MAP offset - A/C on?

Post by antus »

Yes I believe that is right. When the MAP sensor has failed (DTC 33 or 34) one of the defaults are used (see the item names) then a modifier is applied based on throttle position and TPS modifier the result is checked to be in range (between MAP params - Default MAP lower limit and the type of sensors upper limit, then that value is used. VL400 may be able to confirm further or correct.
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VL400
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Re: MAP params - Default MAP offset - A/C on?

Post by VL400 »

That is correct, only used during a fault condition.
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