Quote:
Originally Posted by Oval_Overload
Ok, first of all, the whole point of this is that I'm using compression braking anyway on the steep hills and stop-n-go traffic around town, so I want to cut the injectors while doing that. The car does have a fuel cut mode, but it is uber suck- I tested it today, the injectors run even when the brakes are applied.
Sorry if I sound condescending, I appreciate everyones input here and I'm just trying to get my objectives across.
99Metro- Do you mean the engine needs to be running, or simply turning?
I ask because with the EOC method I'm using, the engine is turning. I think the tranny pump is pumping whenever the crankshaft is turning. But, heh, I've been wrong before...
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I understand your cost-benefit ratio with using EOC -- I do the same with my automatic, but in Neutral. I've been told that fluid pressure for the lubrication system is absent and puts undue strain on clutch packs and other internals when forced to turn (especially at high speeds) while engaged.
I consulted the shop manual for my vehicle. In this instance, the main shaft should turn and provide pressure for the ATF pump. But, the Regulator Valve determines how much fluid is pumped and where. Here's the basic schematic for its operation...
General Hydraulic Pressure:
ATF Pump -> Regulator Valve into 3 outputs ->
-> Line Pressure (shifting action)
-> Torque Converter Pressure (engagement hydraulic coupling)
-> Lubrication Pressure (Where we want to focus)
The TC's stator rotates via torque from the crankshaft. In conditions of torque (engine running, acceleration), turns a shaft, moves the spring-loaded arm on the fluid pressure regulator and feeds the system with ATF.
As I understand it, torque converter pressure remains when the engine is cut because the regulator valve receives no torque and closes. Now, fluid cannot be pumped into the lubrication system. Clutch packs turn with the absence of sufficient fluid, and can be susceptible to accelerate heat and wear.
It's a complex operation -- if I'm incorrect in how I interpreted this system, then let me know
As always, every transmission model is different, your mileage may vary...
-Rick