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Old 03-19-2017, 11:32 AM   #61
MTX-4
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I only disconnect negative battery terminal (not whole battery), I don't know if this vary in some way if we are talking in terms of "reset" -> this equal to total disconnection as the battery has two terminals.

In the las 2 months I disconnect the battery 2 times, reset adaptation one time and disconnect the MAF with the engine ON to reset LTFT numbers one time. Neither of this things change the LTFT negative tendency. -> then my first speculation cannot sustained as you have already disconnect the battery before. Thanks for telling me as I have never disconnected the battery before even when I replaced the battery a used a small battery connected in parallel to avoid memory lost.

I can add third speculation: Seems like all electrical connectors has been designed with low voltages threshold and the years/corrosion makes lost continuity quality. -> Then this is the most likely root cause.

Thanks for the information



Quote:
Originally Posted by POLGOZ View Post
MTX your speculations have sense. Im my experience, I only disconnect negative battery terminal (not whole battery), I don't know if this vary in some way if we are talking in terms of "reset"
In the las 2 months I disconnect the battery 2 times, reset adaptation one time and disconnect the MAF with the engine ON to reset LTFT numbers one time. Neither of this things change the LTFT negative tendency. The DME bug idea sounds real, but I think... if is in this way and after my several resets and disconnects, why LTFT still failing??
I can add third speculation: Seems like all electrical connectors has been designed with low voltages threshold and the years/corrosion makes lost continuity quality.

and as you say.. engine happier, happy heart
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Old 03-19-2017, 11:35 AM   #62
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Agree with that and it looks like it is the only reason. Thanks jfoj.

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Originally Posted by jfoj View Post
Constant thermal cycling can and will cause the female terminals for sensors to loosen up over time.

You need to pay attention when connecting/disconnecting the connectors to see if the female terminals have enough "grab".

Also many aftermarket sensors do not have the same thickness metal male pins or blades, so this can and is another tricky spot to pay attention to.
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Old 03-20-2017, 01:39 AM   #63
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The DME of this car is a bear to understand and really has a mind of its own.
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Old 03-20-2017, 11:42 AM   #64
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the fact to fisically disconnect the DME is the trick I think. Some kind of clear/reset happens without the voltage input supply. Something unreachable across software reset or battery supply.
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Old 03-20-2017, 08:31 PM   #65
MTX-4
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Agreed. Somehow I felt the before disconnection the DME program is looping in the wrong mode. After each major repair, the procedure for battery disconnection cannot be emphasized enough I think.
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Old 03-22-2017, 07:31 AM   #66
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Hmm, i checked all my connectors, at the maf, at the icv, at the throttle body and at the dme - all looked finde and it didnt made a difference. still stuck at -3.9...-2.3 and -2.3...-1.6.

but what he says in the video makes too much sense:
after resetting the battery everything works for a week or so and then it gets bad again.
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Old 03-22-2017, 02:20 PM   #67
POLGOZ
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Quote:
Originally Posted by sebograf View Post
Hmm, i checked all my connectors, at the maf, at the icv, at the throttle body and at the dme - all looked finde and it didnt made a difference. still stuck at -3.9...-2.3 and -2.3...-1.6.

but what he says in the video makes too much sense:
after resetting the battery everything works for a week or so and then it gets bad again.
Do you disconnect the power supply connectors at the DME?? Im still in -2,3 and 0,0
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Old Yesterday, 04:09 AM   #68
sebograf
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Quote:
Originally Posted by POLGOZ View Post
Do you disconnect the power supply connectors at the DME?? Im still in -2,3 and 0,0


Yes - i disonnected the battery first, then removed all the connectors at the dme, checked everything, replugged everything to the dme and then reconnected the battery.


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