rimpainter.com

Tuning went great. I completely eliminated the ping with the stock injectors. I also re-did the fuel map posted above. I was adding some fuel in strange places. In addition, I found that timing retard was not really needed at low RPM's and with low to moderate throttle position.

Anyway, I do have another question. I don't really understand this dual map thing. Do I just "build" an alternative map on the second tab of both the injection and ignition pages? If so, how do I officially "switch" to the alternative map? In other words, how do I load my "high elevation" map for example via my laptop? Surely there is an easy way, but for some reason it seems too complicated to me. What am I missing?

Thanks!

Ganoid

Any one know where to get the best price on an SMT6? So far $355 shipped is the lowest I have seen. Id like to get one and see what I can squeez out of my 3.0 using an alternative MAF or even a MAP instead.

midiwall

Yeup, in fact, I'm running +2 timing down low.


There are two ways to swap maps (remember though, I'm looking at an SMT5, so you may have to hunt a bit on the SMT6 software).

On the 5, the Windows app has a pick in the drop-down menus for MAP A and MAP B. It looks like on the 6, you'd click on the "A" next to "MAP" in the "Running Condition" section on the main screen.

The SMT will default to MAP A, and when you pick B, each of the three maps, (ignition, fuel and analog) will switch to a different "set". You configure these as you want them for the "B" map, and then you can switch back and forth at will.

Now of course, pulling out the laptop to switch maps is a drag - so...

There's a feature on the SMT that will allow you to flip between the maps with a flick of a switch. All you do is place a simple SPST switch between a wire on the module and GROUND. When the switch is open, you're in MAP A, when the switch is closed, you're in MAP B. On the SMT-5, this is the GREY wire on pin 4, I think it's the same on the -6.

Just extended the GREY wire from the SMT, attach it to one side of the switch, then run a wire from the other side of the switch to a local ground (you don't have to run the wire all the way back to the SMT). That's all there is to it. It'll probably take you longer to find a "cool" spot for the switch than to actually make the connection.

fwiw, my "cool spot" is a small mini-toggle switch into the center console between the front seats.


Have fun!

rimpainter.com

As always, thanks Mark!

MTL_4runner

That's a pretty cool feature to have built in!
What a PITA it would be to constantly load different fuel maps.

midiwall

Yeup. And it's one thing that's rarely brought up in a comparison with SplitSecond hardware.

Christian's looking to use it for altitude correction, I use it for trail work. My 2nd map has more fuel being added down in the bottom end with some additional timing advance. It gives me a bit more twist down low.


The SMT modules are REALLY underplayed. There are a couple of very nice advantages over the SS stuff; the alternate map set; the 3rd "analog map" that you can do anything you want with (7th injector, misting system, etc); being able to work in a lamda mode...

Weasy2k

Dman got in here late Thanks Mark for the replys you are right even on the 6 its teh grey wire
I agree that these units are totaly underplayed...

Right now the SMT6 is being sold for here for about the same 350usd shipped as well
This includes the smt6 unit harness and comm cable.
I also have all the wiring diagrams made up for the 5vz and am in the process of doing the same with the 3vz and 1mz.
The only problem i see with what you want is the whole removing the MAF thing, it takes alot of time and patience to do it with the SMT6 as you haev to manualy set the voltages the smt6 has to provide in each loading cell vs the SMT7 does that all for you My tacoma will show the smt7 using this mafless method and should all be done in November.

rimpainter.com

Drove to work today with no problems, even smoked an Isuzu Trooper really bad

Came out to the rig to go home, and started it up. It ran rough, but then died after a few seconds. I kept it running by keeping my foot on the gas a bit. Tried the dummy plug after it started to die on the freeway. No change. Got it to Autozone where they read the code P0100 VAF bla bla bla. I had them clear the code (it didn't come back) and I got the rig home under full power. I cleaned the MAFS and air filter.

The only things that have changed in the past few days are:

1. I got the rig to run with the SMT.
2. I opened the deckplate.

Do you guys think the "ram air" effect of the open deckplate caused some crap to get on the MAFS? I am really thinking this is unrelated to the SMT. But, I figured this would be a good place to throw it out for discussion.

Anyway, after I cleaned everything and got it put back in, the engine idled funny. It was idling pretty low and bouncing between 600 and 730. I changed the fuel trim calibration to "1" instead of 0 and it idles just fine now. What exactly did I do by making this a 1? I noticed the AFR bouncing between 16 and 20 at 0 and now it stay between 14.7 and 16 at 1. Obviously it made a difference. I just hope my adjustment is ok. Any thoughts?

Weasy2k

could have beena brain fart in the ecu as well...i would have suggested to reset it.
When you changed the number I notice that it also gets the ecu back to working on the trim again as that same thing has happened to me before too. You need to get a OBD-II scanner to help see whats going on with your ecu fuel trim. What was the code? was it really P100 or was it another number?

rimpainter.com

It really was P0100 VAF mass air flow...something rather. I knew immediately it had to do with the MAFS. So far so good. I have to drive it tomorrow so I will let you guys know if anything else acts up. Thanks!

Weasy2k

Are your analog fuel settings set too?
The upper fuel limit should be at or jus tbelow 5v
and the lower to 0v

Just incase any spikes happen for whatever reason the smt6 will never send a voltage greater to the ecu, not that it will completly fry the unit but more on the lines that the ecu will give and error if it sees a spike like that beyond its range, similar to what you saw...

rimpainter.com

I am pretty sure I set the upper limit to 5V, but I will double check that. You know, what you are saying makes some sense. I am wondering if the unit got a V spike somehow and it tripped the CEL? It was on start up, the unit is hardwired to the battery...hmmm.

Is there anything else I can put inline (from batt to the SMT) to "limit" the V getting to the SMT? Is it necessary?

Strange that this is the first time it has happened in probably 30 start-ups.

midiwall

I wouldn't limit the voltage to the SMT, that was the basis of your original problem.

If there was a spike, then you may want to try installing what's sold as a "noise suppressor" (you can get a kit at Rat Shack). It's basically a condensor (capacitor) and a 1:1 transformer that will filter out electrical crap (including spikes). They're used for cleaning ignition noise out of the power lines (the symptom would be static from your radio that changes "pitch" with engine speed) but it will also isolate the power to the SMT from the rest of the rig.


One other thing... I wonder if the stumbling came from the ECU going into fail-safe mode. That would get reset with (I think) 3 key on/key off cycles, or by pulling the ECT fuse under the hood. Fail-safe usually comes up when the ECU just freaks out about an input and can't figure things out. It turns the engine rich and _drastically_ retards the timing.


Oh, and fuel trim wise... the difference between "1" and "0" in a cell (or fuel trim) shouldn't have been enough to cause this. Yes, you can definitely flood the engine using the SMT, but it'll take an adjustment more like "10-12" to do it.



Having fun yet?

rimpainter.com

Oh yeah, this is good stuff! It definitely could have been "fail safe" mode. I didn't have any power (I don't think it would even boost) and it would idle like an old V8.

I might have to look into that part at Rat Shack if this continues to be a problem. Thanks guys!

rimpainter.com

It happened again guys. Went to take a friend to lunch, and it would crank over, catch briefly, then just completely die. Happened 3 times in a row, so I gave up fixing it until later.

Assuming I can get it started, should I try Mark's idea and try to regulate the voltage spikes off the battery?

Should I reset the ECU and see if it will start?

Thanks.

rimpainter.com

OK guys, I went back out to the parking lot and tried a variety of things. I reset the ECU and pulled the negative off the battery. No worky.

I decided to pull the SMT out and put the dummy plug in. However, before I got that far, I unplugged the harness and plugged it back in. Then I noticed a couple wires that I failed to tape the ends of, thus they were exposed and could have been touching a ground. After I made sure those wires were touching nothing it started right up.

So, I have narrowed the problem down to two things:

1. Exposed wires were touching something and freaking out the system
2. By unplugging and re-plugging the SMT it helped somehow.

Any thoughts on those two "fixes?"

midiwall

Yeup... both are valid, but time will tell which one really helped. i.e., if it doesn't happen again, then it was the bare wires; if it happens again and unplugging/plugging the SMT helps then something's getting hung up in the SMT.

Check your power ** and ground ** connections as well. One thing that has always been drilled into my head since the dawn of my electrical experience (decades ago) is that you cannot 2nd guess the importance of a solid ground. If you have any doubts that you're getting a clean ground to the body, then pull it off, sand it down to bare metal and out it back.

rimpainter.com

If memory serves me correct, I don't think I grounded anything to the body. I think I grounded the SMT on a ground going to the ECU. Could that be a problem?

What confuses me is that this has only happened a couple times now, and it is always after it sits for a while in the parking lot at my work. After that, everything works like it should.

midiwall

I would find a real live piece of bare metal on the body and ground it there with a nice sharp-toothed soldered lug.

Everything's soldered, right?


Yeah, but the real thing is that it should _never_ happen, so twice is too much.

Weasy2k

Couldnt have said it better

It looks like something is causing the ecu to freak out. Ever since i rewired my smt6 after my smt7 was ripped out of the truck (stolen ) and pulled wires along with it, my truck runs a whole lot better as i focuesed more on getting a cleaner install done. (wasnt out in the cold like the last time)