-Keith-

Which becomes a pain in the butt loading em everytime over and over

matty-tC

if you're worried about your ecu removing your tune's effectiveness, the whole thing is a headache. reloading the maps is the easier part IMO.

-Keith-

well should be able to piggy back the emange and just cut the power after the emange power wire... but if they use that harness dont see that happening just have to tap the wire after the split that goes to the ecu

raamaudio

The wiring is the easy part

lo_bux_racer

Reseting to base maps (reseting the ECM) by removing power does nothing bad to the ECM, it's a standard troubleshooting technique. Read codes, reset ECM, recheck codes, day in, day out, it never hurts anything. I had to do this for 2 years on my Supra because I had a bad pin on the 5v power to the turbo pressure sensor and the two throttle position sensors. The pin would not make contact if the car had been in temperatures below 45 degrees (F) long enough to fully cold soak. So, I'd go to start the car, and immediately get codes for the ECM and TRAC indicating multiple failures. Once the car warmed up inside the cabin where the ECM is, the connector would make contact, and I couldn't duplicate the failure, so I'd shut it off, reset the ECM and TRAC/ABS systems, and continue driving. This was practically a daily event until I finally broke down and troubleshot it without starting the car or warming it up one cold day. I never expected it to be a single pin on the ECM connector. So enough history.

Here's the big drawback to reseting frequently: TCCS is designed to find the right place to run the engine despite minor faults and despite slowly changing tune over time. If you defeat this by constant resets, you will not get optimum tune for the conditions you are experiencing. For example, you drive from Sacramento to Lake Tahoe (about a 7000 ft climb), shut off the car, go into Harrah's and gamble away your last paycheck in 4 or 5 hours, then go out to the car to go home. Not only have you gained altitude, but you've also seen a significant temperature drop. When we go to start the engine, we're back on default maps, with the tuning our piggyback has either stored or restored based on our original altitude and conditions the day we set it up. Yes, the engine will start, but it may not run very well at all, and the idle is going to hunt all over the place while the ECM tries to figure out what to do with all the changes it needs to make from the base maps. Eventually, it will get moderately happy again, but that may be 30 minutes down the road, so you're coughing and choking trying to climb out of the Tahoe Valley while the ECM is doing it's best to adjust. Then the guy in the Corolla passes you laughing, and you get a bit ____ed off, so you mash the gas, and it hesitates, coughs again, and finally starts to act something like it should, but by this time the passing lane is toast and you're stuck behind the Corolla guy, wishing you had the right maps to work at this altitude.

So, enough stories. Here's the real solution to the problem: http://www.vetronix.com/diagnostics/mts3100/ using the Toyota equivalent of this: http://www.vetronix.com/diagnostics/sps.html

If we were on the DIY-EFI list, the real gurus would be saying, just use a cracked ECM that has the functions you need and program the thing anyway you like. Unfortunately, it's not quite that simple because the cracked ECMs are all GM products. There's nothing inherently wrong with that, but doing the rewiring and getting everything to work is a PITA. Not to mention the reprogramming effort, and the fact that sensor compatibility issues can drive you nuts or into fabrication hell.

I guess it's time to call in the big guns and find out what we really can and can't do with the ECM...

mattssi

stand alone baby

matty-tC

let me know how that goes.

when are you planning your venture into FI on the tC?

Simplyscion

Yea I got the AEM wideband, havent put it in yet but I gotta get a move on it(already had the bung welded into my exhaust,I got a dead 02 sensor there just pluggin it for now)...I have that and two more of my gauges that need to go in and then I am completely finished w/ my setup.

mattssi

The sucky thing about cutting the power too is that other things may be affected. For example, on my automatic turbo IS, when the ecu was reset, my car would not shift. It had to learn my driving style before it started to shift quickly, etc again. This was even after the valve body upgrade, etc.

raamaudio

Seems just no easy answers, not yet at least

Rick

Joe_Dezod

Well, something that caught my eye that I'd like to throw in...

Most people who properly hook up the emanage rung their power from what the stock ecu gets. So theoretically when the power is cut to the ECU, so is the emanage. I know almost everyone is aware of this so far, but here's the cool part... Greddy is SMART when it comes to electronics. They use a static memory system. This means that if power is completey eliminated, memory is not lost, just stored like a hard drive. When you boot the emanage back up, it's still good to go, just how it was before. I think they did this because of firmware updates. It takes a while to update firmware on the emanage and it's very finicky making it difficult to do it right. So if someone were to change the batter (thus resetting the ecu), the user would have to re-update the emanage? I think not... Needless to say, you can cut power all you want, even unplug the emanage and walk around with it. When you go back to plugging it in and turning it on, it's the same as it was before.

I hope that shed's some light to the situation! We're working on a system for our kits as we speak. Hopefully it will never be a problem on our cars, if it is, we already have a fix.

Simplyscion

Yea, it goes for the same thing with the camcon. I tested that theory out last month when I decided to plot all my camcon settings on the graph to save em and try to reset the camcon. No matter what I did, whether I unplugged the camcon unit itself, or reset the ECU by disconnecting the battery cable, it would hold its settings.

mattssi

I've personally never heard of anyone having to reload the emanage when cutting power, etc. However, the other problems still exist w/ automatic trans shifting (if this car even learns)...also, with bigger injectors, etc, after a reset, my IS would be pretty rough until it figured out how to idle right. After that it was fine.

All these little issue are a pain to deal with.

Hopefully you guys can bypass these learning issues, because that will be a huge deal.

lo_bux_racer

Here's the answer to the question about Powertrain Control Module (PCM the new name for ECM) reprogramming from my best source:

Here is some interesting info as well

So, now all I need to do is cough up $8k for the Vetronix gizmo, and who knows how much for the software, and then hope that I can disassemble enough of the information to figure out how to write my own non-Toyco approved updates with the appropriate checksums so they will actually load and run. That might be a tad tricky if I am planning to keep my day job.