Does The Injection Cut Off During Coasting The Car In Gear ???
#1
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Does The Injection Cut Off During Coasting The Car In Gear ???
THIS DOES NOT INCLUDES ME ! But here is the thing> on THIS forum a lot of people clam, that fuel injection cars have their engine management system design so, that during coasting/rolling your car in gear down the hill or approaching to the Stop or red light, and your foot is off the gas pedal during that time, the system automatically turns the fuel injectors OFF, completely!!!
Does the fuel injected Mazda RX-7, FB, FC, FD, even RX-8, have its inejection cut off in those conditions ???
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Does the fuel injected Mazda RX-7, FB, FC, FD, even RX-8, have its inejection cut off in those conditions ???
#3
Engine, Not Motor
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How many times do we have to go over this?
Do you really want to know for sure? Search Google for "Bosch L-Jetronic EFI Manual". This covers the 1st and 2nd gens and describes over run fuel cut from the "horses mouth", so to speak.
I do not know what EFI system the 3rd gen and RX-8 run, but it should be easy to find out with some searching.
I'll try another approach in reasoning. If the cars did not cut fuel on decel, drivers behind you would be bathed in unburned fuel from the tailpipe. Cats would not last more then a few weeks, and mileage would suck. In addition, the rotor housings would become washed down with fuel and engine wear would increase exponentially. Oh, and the car will buck and misfire.
All you need to do is read up on some EFI basics to learn about decel/overrun fuel cut.
Note that in order for this to work on the stock RX-7, the TPS must be able to read closed throttle.
Do you really want to know for sure? Search Google for "Bosch L-Jetronic EFI Manual". This covers the 1st and 2nd gens and describes over run fuel cut from the "horses mouth", so to speak.
I do not know what EFI system the 3rd gen and RX-8 run, but it should be easy to find out with some searching.
I'll try another approach in reasoning. If the cars did not cut fuel on decel, drivers behind you would be bathed in unburned fuel from the tailpipe. Cats would not last more then a few weeks, and mileage would suck. In addition, the rotor housings would become washed down with fuel and engine wear would increase exponentially. Oh, and the car will buck and misfire.
All you need to do is read up on some EFI basics to learn about decel/overrun fuel cut.
Note that in order for this to work on the stock RX-7, the TPS must be able to read closed throttle.
#4
Per the 93 Service Highlights Manual, page F-38:
"Deceleration fuel-cut
To improve fuel economy during engine high-speed deceleration, the fuel suppy is stopped based on signals from the various sensors and switches.
During half-throttle, deceleration, fuel injection to only the front rotor is stopped to decrease deceleration shock."
There is then a table showing the various engine speeds where decel fuel cut is initiated and ceased for both half-throttle and fully closed throttle cases.
"Deceleration fuel-cut
To improve fuel economy during engine high-speed deceleration, the fuel suppy is stopped based on signals from the various sensors and switches.
During half-throttle, deceleration, fuel injection to only the front rotor is stopped to decrease deceleration shock."
There is then a table showing the various engine speeds where decel fuel cut is initiated and ceased for both half-throttle and fully closed throttle cases.
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armans
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08-15-15 09:08 PM