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What triggers the Barometric pressure reading?

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Old Sep 7, 2002 | 06:30 PM
  #1  
CMNTMXR57's Avatar
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Default What triggers the Barometric pressure reading?

In one car I have, I occasionally, on high humidity, high dewpoint days, I go start it and it misfires. Cylinder #6 is always the culprit.

Anyway, I've changed the plugs, wires, and even swapped the coils in order to eliminate a bad coil possisbility but it still always misfires #6.

As I went through the freeze frame data, the only item that is out of whack is the barometric pressure. Specifically, it has read 71+ inches of Hg! That is a far cry from the actual 29-30 inches of Hg. I think the highest barometric pressure recorded on Earth has been like 31 inches, so you can see, 71+ is Waaayyyyy off!

This is why I'm thinking this is the culprit...whatever reads the barometric pressure.
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Old Sep 7, 2002 | 08:27 PM
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Default Re: What triggers the Barometric pressure reading?

MAP sensor...
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Old Sep 7, 2002 | 09:03 PM
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Default Re: What triggers the Barometric pressure reading?

You sure your scan tool was set to Inches Mercury, and not kPa (kilopascals)? 29.92" Hg = 101.5 kPa, so a reading of 71 kPa is entirely possible and normal for a motor under acceleration.

-Andrew
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Old Sep 9, 2002 | 12:13 AM
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Default Re: What triggers the Barometric pressure reading?

No, it said in "in Hg" Plus once the car is running, it goes back to a normal 29+ Hg's.

Right after I got done posting this, we went out to go somewhere so I moved the car and it did it right then, just not long enough to set a code.

Edit:
After driving a little, it goes away and drive like normal. I'm thinking I may be looking at doing a injector cycling test on #6 to see if the injector itself is the culprit. But this high Barometric pressure reading still bothers me.

<small>[ September 09, 2002, 10:41 AM: Message edited by: CMNTMXR57 ]</small>
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