datamaster histogram question
Thread Starter
Racer
Joined: Sep 2004
Posts: 258
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From: Coram NY
datamaster histogram question
I ran my 86 out on the hwy for a good 45 minutes and recorded the session. I was trying to understand the histogram, the fuel cells were mixed white and light green, some dark green no red. the notes state white is optimum fuel, green is lean. if the cells are green, does this mean the ECU will try to richen the mixture to bring the cell to white or optimum mixture. Or is this just saying the that it running lean and is OK.
Thanks,
Tom
Thanks,
Tom
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
The integrater, short term numbers are the ecm trying to correct the lean cells. There is a limit to what it can do here. If you have an adjustable fp regulator you can bump up the pressure and see if it helps.
Thread Starter
Racer
Joined: Sep 2004
Posts: 258
Likes: 0
From: Coram NY
I failed emissions for HC (almost double the limit) the mechanic said it was either running rich or a bad catalytic converter. That is what prompted this test.
Tom
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
I dont have emissions so I dont know what to say on that. A little pale green or a little pale pink wont hurt the motor. All white is theoretically the best but my car seems to run and drive better a little rich. Maybe post this in C4 Tech and more guys will see it and add some advice.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
If you have the histogram up when running a log you will see the colors change in the cells as the engine runs.
The color you end up with is a average so 5 reds and 5 greens would give white even though that cell was rich and lean at times ( highly unlikely )
If you click on a cell you can see how many times that cell has been hit on during the log
The color you end up with is a average so 5 reds and 5 greens would give white even though that cell was rich and lean at times ( highly unlikely )
If you click on a cell you can see how many times that cell has been hit on during the log
Thread Starter
Racer
Joined: Sep 2004
Posts: 258
Likes: 0
From: Coram NY
If you have the histogram up when running a log you will see the colors change in the cells as the engine runs.
The color you end up with is a average so 5 reds and 5 greens would give white even though that cell was rich and lean at times ( highly unlikely )
If you click on a cell you can see how many times that cell has been hit on during the log
The color you end up with is a average so 5 reds and 5 greens would give white even though that cell was rich and lean at times ( highly unlikely )
If you click on a cell you can see how many times that cell has been hit on during the log
On the long term, if the cells remain green, is that telling me that the ECM will be constantly trying to richen the mixture?
Thanks,
Tom
