Question about torque converter clutch solenoid and other stuff

[thaharlequin]

-Can I run a separate switch to the TCC in order to engage it manually?

-I've read that straight three cylinder engines tend to be bouncy due to not having an opposing cylinder, so would a V6 still be pretty smooth w/ one bank disabled since it has opposing cylinders?

-Lastly, does open loop have maps for the entire range of TPS signals, or will it just dump a ton of fuel in there w/ no Oxygen sensor inputs?

The reason I ask is because pumping losses for most of my driving are the biggest culprit in terms of inefficiency. If I disable one bank when cruising I could decrease pumping losses and increase engine efficiency, but in order to do that I need it to stay in OD, so the TCC would have to stay locked. Those two I think are doable, however, even if they are, I would still need to know/figure out if the ECU has open loop maps for all sorts of different inputs from the TPS because if it just ran super rich w/o the Oxygen sensors there would be no point. The problem w/ leaving the Oxygen sensors in the mix is that they'll see a lot of air from the three cylinders w/ injectors that aren't firing, and because of this the three that are on will run super rich from the ECU trying to compensate for all the additional air. So, ideally, if the engine runs smooth enough w/ just one bank and I can manually lock up the TCC, so long as the ECU can operate over all the usual TPS/other sensor ranges while having the oxygen sensors unhooked w/o going super rich, I should be able to see ~50mpg cruising at ~60mph.

[ASG14]

Um, wtf? You run on 1 bank on 1MZ, you'll like kill your engine, fast, and get 1/2 the gas mileage, and blow sensors left and right. Enjoy replacing your O2 sensors at $100+ a pop.

[thaharlequin]

Originally Posted by ASG14

Um, wtf? You run on 1 bank on 1MZ, you'll like kill your engine, fast, and get 1/2 the gas mileage, and blow sensors left and right. Enjoy replacing your O2 sensors at $100+ a pop.

It's a 3VZ, but naw, I wouldn't kill O2 sensors unless it ran really rich. Like I said before, if it'll run w/ no Oxygen sensors on the inputs from other sensors reasonably well, then it should be o.k. Which is why I'm asking about how well it can run in open loop. Can it do part throttle in open loop o.k. just based on the IAT and TPS inputs?

As for killing the engine, I doubt it. The only difference between killing fuel on a V6 and current cylinder deactivation of V6/8 engines would be that instead of staying closed the valves would keep on doing whatever it is that they're doing. Manufacturers keep the cylinder valves closed when killing a bank because, like I said, if the other three or four cylinders in a V-configuration pump air in the the exhaust, the ECU will think that the remaining three are running lean from all the extra air, and naturally oxygen, and dump a load of fuel into the 3/4 cylinders that are operating, killing any efficiency gains, and probably making stuff worse. Otoh, since in my case I can just unplug the Oxygen sensors, I'm wondering if the ECU will freak out in part-throttle open loop and dump a bunch of fuel in, or if it'll run normally, just not at exactly 14.7:1 all the time, kinda like an older carb'ed engine. If it runs normally more or less, I don't see how I wouldn't improve fuel efficiency, and if I want all six again, I can just flip the deactivated bank back on.

Anyway, I'm guessing that it'll run reasonably well, since my friend's dad had a 4cyl Dodge w/ a messed-up Oxygen sensor that would run like crap once it was started up until the ECU figured out that something was wrong and then the CEL would pop-up and it would run normal. But, since I don't feel like melting my cats/gumming up my O2 sensors if it does end up running super-rich at part throttle in open loop, I figured it'd be best to ask first.

[Eye8Pussies]

Originally Posted by thaharlequin

It's a 3VZ, but naw, I wouldn't kill O2 sensors unless it ran really rich. Like I said before, if it'll run w/ no Oxygen sensors on the inputs from other sensors reasonably well, then it should be o.k. Which is why I'm asking about how well it can run in open loop. Can it do part throttle in open loop o.k. just based on the IAT and TPS inputs?

As for killing the engine, I doubt it. The only difference between killing fuel on a V6 and current cylinder deactivation of V6/8 engines would be that instead of staying closed the valves would keep on doing whatever it is that they're doing. Manufacturers keep the cylinder valves closed when killing a bank because, like I said, if the other three or four cylinders in a V-configuration pump air in the the exhaust, the ECU will think that the remaining three are running lean from all the extra air, and naturally oxygen, and dump a load of fuel into the 3/4 cylinders that are operating, killing any efficiency gains, and probably making stuff worse. Otoh, since in my case I can just unplug the Oxygen sensors, I'm wondering if the ECU will freak out in part-throttle open loop and dump a bunch of fuel in, or if it'll run normally, just not at exactly 14.7:1 all the time, kinda like an older carb'ed engine. If it runs normally more or less, I don't see how I wouldn't improve fuel efficiency, and if I want all six again, I can just flip the deactivated bank back on.

Anyway, I'm guessing that it'll run reasonably well, since my friend's dad had a 4cyl Dodge w/ a messed-up Oxygen sensor that would run like crap once it was started up until the ECU figured out that something was wrong and then the CEL would pop-up and it would run normal. But, since I don't feel like melting my cats/gumming up my O2 sensors if it does end up running super-rich at part throttle in open loop, I figured it'd be best to ask first.

you got it right on the first part- i.e. the oxzgen sensors thinking that it is lean because of the extra air

and unfortunately,you also got it right on the second part about the ECU going wasting a lot of gas when the oxygen sensors either read lean/rich or no signal

[thaharlequin]

Originally Posted by Eye8Pussies

and unfortunately,you also got it right on the second part about the ECU going wasting a lot of gas when the oxygen sensors either read lean/rich or no signal

How much gas? Does it tend to run a bit rich across the entire map (I could lean that out via the AFM cog?) or does it use the WOT injector duty cycle all the time regardless of TPS/AIT? The first one I think I could deal w/, but the second one seems incredibly stupid considering GM can make a OBDI car that'll run w/o oxygen sensor inputs w/o going super rich and stalling, but Toyota didn't?

[Venom_5]

you would be better off killing fuel and spark on 2 cylinders for symmetry ... and if youre going to take on a project like this, might as well get a standalone so you can control the maps however you want, rather than letting the stock ECU attempt to sort through the mess

however, like ASG hinted at ... with a project like this, running the entire drivetrain how it wasnt built to be run ... prepare for broken parts

[toyomoho]

Didn't Honda come up with a 3.5L V6 having i-VTEC variable cylinder management.

Don't you need to keep the valves closed when their not working.

[thaharlequin]

I now understand why manufacturers close the valves! In V engines manufacturers don't keep 'em closed because of emissions. For instance I've passed smog w/ only one operable Oxygen sensor, RB and post cat were both giving me codes, so as long as I unhook the post-cat sensor and the one on whatever bank I'm not using, I should be fine in terms of the active one on the active bank keeping everything around 14.7:1. Am I correct in assuming that when facing the engine and starting from the left, the intake manifold passageways run (FB=front bank/RB=rear bank) RB/FB/RB/etc... and that the top three runners on the air intake plenum go to the rear bank while the bottom three go to the front bank?