Cold Starting Issues...
#31
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Not any more. Back in the carburetor days fast idle was really fast - 1200 to 1500 rpm and it was adjustable with a screw usually over two steps. With modern engine management, I've seen much lower cold cycle rpm increases - usually about 200 or 300 rpm over idle - and the engine management is intentionally running rich to fire up the catalysts. Oil pressure on initial start is always good, but as soon as you get some heat in the oil it thins out and idle oil pressure drops like a rock. The theory is, you're not moving the car at idle so the rod bearings aren't under any significant load. Oil pressure doesn't need to be high if there's no load. It also saves horsepower because pumping oil takes energy just as any other accessory drive does. So we see low oil pressure at idle after a few minutes of operation. Letting the engine idle to full operating temperature has got to be about the most wasteful thing you can do.
#32
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Not any more. Back in the carburetor days fast idle was really fast - 1200 to 1500 rpm and it was adjustable with a screw usually over two steps. With modern engine management, I've seen much lower cold cycle rpm increases - usually about 200 or 300 rpm over idle - and the engine management is intentionally running rich to fire up the catalysts.
I'm with you, BTW on carburators......for MANY reasons, they were a PITA. EFI, without a doubt, is one of the best automotive inventions of all time.
Last edited by mmarshall; 01-13-10 at 08:14 AM.
#33
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My current F and previous 350 both peak at about 1200 rpm in neutral on a sub-freezing morning (we've had an unfortunately large number of these in the last couple weeks). If it's anything above freezing its 100 rpm. Idle is 700 - 800 according to the book and the tach.
Every once in awhile I miss the old Stromberg. Then I wake up from the nightmare and thank God for EFI!
Every once in awhile I miss the old Stromberg. Then I wake up from the nightmare and thank God for EFI!
#34
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32 degrees is a heat wave for us here in NYC![Stick Out Tongue](https://www.clublexus.com/forums/images/smilies/tongue.gif)
I don't belive you guys in Florida get the winter blend fuel as we do here in the North East. Non winter blend fuel can freeze up with temps 32 & below. You should purchase a bottle gas line anti-freeze for those cold days & pour it into your gas tank. Let us know how this pans out. I bet you will notice quicker starts.
Good luck.
![Stick Out Tongue](https://www.clublexus.com/forums/images/smilies/tongue.gif)
I don't belive you guys in Florida get the winter blend fuel as we do here in the North East. Non winter blend fuel can freeze up with temps 32 & below. You should purchase a bottle gas line anti-freeze for those cold days & pour it into your gas tank. Let us know how this pans out. I bet you will notice quicker starts.
Good luck.
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