Simple repair gone wrong...
02-09-2005, 08:38 AM
#21
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Yup, I had a friend when I was young open a radiator cap on a old firebird that he thought cooled
down but wasn't. He had 3rd degree burns I think on his neck, chest and 1 of his arms. I'm trying to remember he might have had his shirt off at the time...or just a little *** t-shirt. I learned my less then. When it came time in my life to work on cars, I respect the coolant. ;-p
02-09-2005, 09:09 AM
#22
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do you need this?
Engine Coolant Temperature Sender (059 919 501 A - $6.47)
Engine Coolant Temperature Sender Seal (O-Ring)(N 903 168 02 - $1.40)
Engine Coolant Temperature Sender Spring/Clip(032 121 142 - $0.50)
He got the parts from Agincourt Autohaus.
Engine Coolant Temperature Sender Seal (O-Ring)(N 903 168 02 - $1.40)
Engine Coolant Temperature Sender Spring/Clip(032 121 142 - $0.50)
He got the parts from Agincourt Autohaus.
02-09-2005, 09:37 AM
#24
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Roughly speaking, it's when the air/fuel mixture in the cylinder explodes at the wrong time...
This causes audible "knocks". I'm sure others can give a more technical explanation.
02-09-2005, 09:47 AM
#26
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It's a little more general than that...
I can't give a textbook definition either, but I can think of a number of examples of things that would cause misfiring.
In more general terms, I think it's when the air/fuel mixture doesn't ignite properly. The end result is the energy from combustion in that cylinder isn't converted to mechanical energy, so depending on how bad the misfiring is, you might not feel much other than a brief stutter, or you might feel like you're missing a cylinder.
This could be due to a timing issue, and issue with the ignition system/coilpacks/plugs, an issue with the fuel injectors, or an imbalance in the air/fuel ratios. A few more causes come to mind that fall outside this definition, so I suspect the definition still needs to be broadened, but that's my best stab at it.
In more general terms, I think it's when the air/fuel mixture doesn't ignite properly. The end result is the energy from combustion in that cylinder isn't converted to mechanical energy, so depending on how bad the misfiring is, you might not feel much other than a brief stutter, or you might feel like you're missing a cylinder.
This could be due to a timing issue, and issue with the ignition system/coilpacks/plugs, an issue with the fuel injectors, or an imbalance in the air/fuel ratios. A few more causes come to mind that fall outside this definition, so I suspect the definition still needs to be broadened, but that's my best stab at it.
02-09-2005, 09:58 AM
#27
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You've listed causes of a misfire but the actual misfire itself is an explosion at the wrong time...
Just to clarify since he asked *what* is a misfire instead of what causes it. But you have a good list of causes that helpe explain why it occurs.
02-09-2005, 10:11 AM
#28
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Let's take a cause and backtrack to your definition...
Cause: Dirty spark plug
Definition: ..."explosion at the wrong time..."
Doesn't quite fit, does it? The dirty plug could be creating the spark at the right time, but the result could be an incomplete burn.
My second paragraph doesn't list causes...I restricted that to the last paragraph. The second paragraph was intended to answer his question.
Definition: ..."explosion at the wrong time..."
Doesn't quite fit, does it? The dirty plug could be creating the spark at the right time, but the result could be an incomplete burn.
My second paragraph doesn't list causes...I restricted that to the last paragraph. The second paragraph was intended to answer his question.
02-09-2005, 10:27 AM
#30
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right. misfire == very general. could be incomplete burn, early or late fire
any of these can cause an audible knock. any of them may not cause an audible knock but will almost certainly register at the knock sensor.
most of the time if it's bad enough you feel this as a stutter especially under load. sometimes accompanied by knock.
did that muddy the waters? :-)
most of the time if it's bad enough you feel this as a stutter especially under load. sometimes accompanied by knock.
did that muddy the waters? :-)