Freezing the Slushbox. Torque Converter on-demand lockup switch. - Page 21 - Fuel Economy, Hypermiling, EcoModding News and Forum

saand · 10-15-2010, 09:31 PM

mechman600 you can get around the system overriding your control by using a double pole double throw switch which will override both the 12v and 0v to the solenoid. However i have found i very rarely override the TC (torque converter) in 1st or 2nd gear and i do sometimes forget to unlock the TC when im stopped at lights in neutral so i end up stalling the car and looking like an idiot. So maybe your car overriding your override is a good thing.

For anyone interested i have also written up a wiki on this mod which should tell people how to perform the mod. It is however lacking info about PWM as my system worked without any PWM so if anyone has any info about this feel free to put it in the wiki
Torque Converter Lockup - EcoModder

there is also a wiki for the manumatic conversion.

I am also thinking of making an electronic controller that will perform the gear changes and TC lock up for me because i get very busy when im driving now with pulse and glide and TC lock up and gear shifting. If i end up getting around to this I will post up a schematic or PCB design for everyone.
For anyone that is thinking why would you turn it back to an automatic. The benefit is the electronic controller will control the TC and gears how I want it to rather than how the car manufacturer designed it.

Frank Lee · 10-15-2010, 10:20 PM

Oof, that extra cold start might be negating the benefits.

George Tyler · 03-11-2011, 12:46 AM

Hi Orangeboy, I also have a Previa, does your solendiod take continuos 12V? I was thinking of using the O/D switch on the end of the gearchange lever, don't think anyone ever turns it off.... but then, maybe a relay that latches from a momentary action sw and releases when the brake pedal is pressed would be betterdo you know which 12V supply to the ECU is the right one to use for the supply to the switch?

orange4boy · 03-11-2011, 01:58 AM

I just use a continuous 12V supply with no problems and have taped a switch to the shift column. That way it's otherwise stock. Any more clever arrangements will have to wait till I have some spare time. I doubt I will ever change it because now it''s so simple and reliable. Anyone can still drive it as long as I leave the TCL switch off.

I wouldn't use the OD switch as the TC Lockup because it's effectively your 4th gear. You will need that so it does not shift straight from 2nd to 4th. In first gear the lockup does not work. The Previa shifts to second from park for an instant then to first to avoid that jerk that the NVH guys in engineering don't like so it sometimes stalls if you forget to switch it off at a stop.

The routine from a stop is: OD off, Lockup off. Green light go, shift from N to second. (Previa will start in first and shift to 2nd around 8 mph which is too low an rpm to lock up in.) Accel to 15mph (25kph) and then switch on TCL and accel to 25mph, shift to D (3rd), accel. to 40mph, switch OD on (4th). Enjoy the feel of a standard.

I takes a bit of getting used to but you won't want to go back to stock. It will lockup solid even on steep hills but if it starts to slip better to unlock then risk wearing it out. That's only happened under full load and full throttle.

Hope that's clear as mud.

George Tyler · 03-12-2011, 09:27 PM

I made a controller box for it, idea is what when I push a button it latches a relay, and a dab on the brake pedal releases it. works great. I see there is a problem in that there is no spring , a manual transmission has springs in the middle of the clutch plate to absorb vibration but the auto does not, so if the RPM drops to below 2000 the car vibrates terribly.

orange4boy · 03-13-2011, 05:40 AM

I only get vibration below about 1200 - 1500 rpm. It's a bit worse than a manual for sure so you can't shift quite as early.

George Tyler · 03-13-2011, 06:05 AM

this is what it looks like, very amaturish! but it works.... will make another one with a Pic processor that monitors the RPM and cuts off below 1500 RPM.

RH77 · 03-23-2011, 04:40 PM

Hey All...

I took the Integra on a trip today and noted some odd behavior from the TC. Normally, when the TC Engagement Switch is closed, the TCU will allow partial, half, or full lockup depending on warmup conditions and throttle position. It has worked great for a long time...

Today, it started to kick in-and-out on the highway at speeds of 40-65 mph. At a TPS of 18 in D4, it would remain unlocked, where a solid TPS of 24 would mostly demand full lock (but not always). It used to lock after TPS-17 and hold (after warmup).

The only difference since last operation is warmer temperatures (in the 60's). I'm puzzled where to begin diagnosis -- the switch is functional and consistent. I'm thinking of resetting the ECU (battery disconnect) and if that doesn't work, tighten the throttle cable to the transmission. Hopefully the TC solenoids aren't failing (maybe a check of the fluid too). Any ideas???

Thanks...RH77

orange4boy · 03-24-2011, 03:11 PM

This has happened to me on a couple of occasions but it always turned out to be a bad connection somewhere in my wiring or in the switch I chose. Start there first and check your fluid level also.

RH77 · 03-25-2011, 06:38 PM

Quote:

Originally Posted by orange4boy

This has happened to me on a couple of occasions but it always turned out to be a bad connection somewhere in my wiring or in the switch I chose. Start there first and check your fluid level also.

I found out what has been causing the problem: it blew a transmission cooler line. The fluid was low, so I filled it and went for a test drive. I noticed a trail of fluid down the driveway and a pool in the garage. Most of the ATF was back on the floor and had squirted onto most of the radiator and other parts as far back as the rear exhaust hanger (yes, it was all over the place).

After removing the fan, there it was -- a chopped-up line. It looks like it might have gotten too close to the fan and has a nick out of it, but was now spewing steam when running

Before taking the fan off, I didn't know what to think -- catastrophic failure!!! But this solution is probably the easiest to repair than the other alternatives I feared...

Hopefully driving 100 miles or so on very little fluid didn't damage the transmission too badly. The fluid is synthetic, so I'm banking that it has some extra lubrication properties. My next concern is any breakdown of rubber/plastic from contact with the fluid. Is brake cleaner the best way to clean this stuff, or does it pose no problem?

RH77