993 Weird Computer MPG Issue
Discussion
Hello all
I’m looking for some help from some fellow 993ers that have a car with an On Board Computer.
Everything on the OBC works as it should, the MPG screen (or in my case L/100km screen) seems to read sensible values while driving (aware these are never 100% accurate) except that it seems to measure fuel consumption when the engine’s off but ignition on. Making the Ave MPG look much worse if I ever leave the ignition for a few minutes then start the car.
The car runs very well and I can say for certain that no fuel is being used or lost while the ignition is on!
There’s no real negative effect but there seems to be a glitch in the system, I wonder if anyone else with a 993 with OBC could try turning their ignition on and look at the MPG gauge to see if it does the same?
Thanks all in advance!
I’m looking for some help from some fellow 993ers that have a car with an On Board Computer.
Everything on the OBC works as it should, the MPG screen (or in my case L/100km screen) seems to read sensible values while driving (aware these are never 100% accurate) except that it seems to measure fuel consumption when the engine’s off but ignition on. Making the Ave MPG look much worse if I ever leave the ignition for a few minutes then start the car.
The car runs very well and I can say for certain that no fuel is being used or lost while the ignition is on!
There’s no real negative effect but there seems to be a glitch in the system, I wonder if anyone else with a 993 with OBC could try turning their ignition on and look at the MPG gauge to see if it does the same?
Thanks all in advance!
My recollection is that the OBC calculates fuel use based upon injector pulse information from the ECU and speed/distance information. If the engine isn't running the ECU shouldn't be sending out any fuel consumption info. But I no longer have a 993 so can't check anything.
Has the ECU been modified in any way?
And, out of curiosity, why are you leaving the ignition on without the engine running? I believe that's not healthy for the ignition coils.
Has the ECU been modified in any way?
And, out of curiosity, why are you leaving the ignition on without the engine running? I believe that's not healthy for the ignition coils.
AW10 said:
My recollection is that the OBC calculates fuel use based upon injector pulse information from the ECU and speed/distance information. If the engine isn't running the ECU shouldn't be sending out any fuel consumption info. But I no longer have a 993 so can't check anything.
Has the ECU been modified in any way?
And, out of curiosity, why are you leaving the ignition on without the engine running? I believe that's not healthy for the ignition coils.
Interesting, thank you. Has the ECU been modified in any way?
And, out of curiosity, why are you leaving the ignition on without the engine running? I believe that's not healthy for the ignition coils.
The ECU is completely stock, as is everything else that could affect the computer.
I noticed this after installing or changing a few components that need the ignition on for a few moments to test (horn, dipped beam, washer motor, oil pressure sensor etc..), and I noticed the consumption going up on the screen. So I’m certainly not turing it on when I don’t have to!
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