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2009 Mazda Mazda6 - popping the clutch vs. using jumper cables?

My daughter’s clutch-equipped car would not start due to weak battery. Instead of searching for my jumper cables I suggested drifting slowly down our hill and “popping the clutch” like we used to do often back in the “dark ages” of the 1960’s. She looked at me with that “how old are you again?” frown. We opted for the jumper cables. My question … is it still okay to use the “pop the clutch” method to start more modern automobiles … or could it cause harm to today’s more sophisticated electrical systems, etc.?

It is OK but may not work at all depending on how flat the battery is. The electronics won’t work below 9 volts or so.

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I still use the pop-start method to get a vehicle started when it’s dropped off with a dead battery/shot starter if it has a clutch

I have yet to see any problem using the method.

Tester

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[quote=“Dave491, post:1, topic:155490, full:true”]
My daughter’s clutch-equipped car would not start due to weak battery. Instead of searching for my jumper cables I suggested drifting slowly down our hill and “popping the clutch” like we used to do often back in the “dark ages” of the 1960’s. She looked at me with that “how old are you again?” frown.

I know that look well & agree with mustang;s advice.

I’ve used that method successfully a number of times when my Corolla battery wouldn’t crank the engine. It never caused any problems for me. I’ve heard a theory that with modern computerized injection systems doing that could cause too much gas to flow into the cat and possibly damage it. The idea proposed is that the computer only knows how much fuel to inject during cranking if the cranking is done with the key in “start”. Cranking the engine with the key in “on” confuses it and results in too much fuel injected. Like I say, nothing like that has happened for me. I expect that theory is probably bogus.

As long as the battery has enough juice to run the fuel pump, popping the clutch should work.

That was my initial thinking too.
But now I suspect as long as the battery has enough juice to excite the alternator field, then jumping it would enable the alternator to generate enough voltage to run the fuel pump. It will take a second or two longer to jump, but it should work.

I have done literally thousands of clutch-starts with cars and motorcycles. Zero problems with it.