Ali SC3

iTrader: (10)

you think it could have something to do with setting it at 8 degrees. I know it idles a little better with it at 10 but I would be worried about the timing then in other parts.

I think both of those are a resistor fix. egr insufficient flow I think is from the egr temp sensor reading off. a resistor fixes that one also I want to say.

Ali SC3

iTrader: (10)

For the gs300 engine harness, you can use the schematic of the main 3 sc300 ecu plugs, its the same.
What is different is the body plug harness, on the sc300 its like 3-4 small plugs by the ecu plugs, on the gs300 its 1 large body plug with a funny shape next to the ecu plugs.

Since your swap is in a different car, you can probably use either harness the engine side is practically the same for similar years.

also for the body plug, you can look up online there are pinouts of aristo's that have the same/similar 1 large body plug if you cannot find a gs300 schematic.

like this is a 2jzgte wiring for an aristo (JDM 2jzgte gs300).
its going to look alot like what you will make your harness into, and below has the body plug stuff also for like dash stuff and relays etc..
http://wilbo666.pbworks.com/w/page/3...ngine%20Wiring

you will see the main 3 ecu plugs are the same on all non vvti... sc300, gs300, mk4 supra turbo and non turbo, and aristo.
some pins are different between n/a and turbo but just follow the thread and reference those for the rest.

187

I tired ruining it at 10 and it made no difference at idle so i didn't try to run it even on 6psi. I'm just thinking the ttecu doesn't like the sensors in the stock throttle body for some reason.

myLEXsc400

So does this mean that a code for EGR flow excessive is a a resister fix too? How do I go about doing that?

My car still has codes that pop up after a bit of driving for a misfire on every cylinder, and a code for exhaust gas recirculation flow excessive. Is it possible the EGR is leaking and causing the misfire? I l cleared the codes a couple days ago to see if changing the MAF to a newer one makes a difference (it didn't), and this morning when the CEL came back on, it started flashing. Its never flashed before. The car drove like it was really struggling to move with every gear change. I have no idea what this might me. No new codes except misfires and EGR

Ali SC3

iTrader: (10)

when its flashing I think it means that its pending as it not permanently stored yet, if it continues then it might become solid. I dont remember the resistor its either that or you have to plug in a vsv there but its not as big of a problem as the misfire stuff, and lets see if they are related as you said.

I have definitely put back on the stock intake several times where I had a leak at the EGR pipe. you have to use like new gaskets or some of the high temp silicone stuff to get a good seal there. If you have a small leak there it will actually be an intake leak or an exhaust leak and could easily cause misfire codes and run poorly.

did they leave the whole EGR in tact on your car? the part that sometimes leaks is where the metal egr pipe comes down and attaches to the lower runner and that causes an exhaust leak which messes with the system (if you stick your hand down there when you first start the car so its cold and you don't burn your arm, you will be able to feel pulses of exhaust gas coming out if there is a leak there and it will get hotter and hotter), or really anywhere on that metal pipe even where it comes out of the Y part of the intake (causes a vacuum leak which is arguably worse). also check the big nut on the metal pipe you sort of need a large monkey wrench to tighten it, that has to be leak free joint as well and sometimes it turns on installation and loosens up some (would create a vacuum leak on intake again).

BuffNStuff

From what I understood, the flashing CEL meant missfires were detected and it's warning you that the catalytic converter is in danger of being damaged. This happened to me when I first started driving my car on the stock ecu after doing the turbo install. I had missfires everywhere and the unburned fuel was dumped into my exhaust and melted my cat.

Ali SC3

iTrader: (10)

well it does look like that is it I just did a search on flashing cel and it said due to sever misfires.

How could the shop not notice the cause of severe misfires, I just don't understand.

Buff how did you get rid of it and do you still have the egr on the car?

Bad injectors I can see misfires on one or two cylinders, but to get them on all cylinders now that sounds like a decent leak or a bad ecu. I do remember where someones capacitor leaked on all the injector traces and would short them out randomly, that could very well be happening also if everything mechanical is checking out. wouldn't be the first time someone doing this mod has got a ecu on the fritz. I think I remember a few bad map sensors as well.

Also I did some reading online it seems alot of IS300 cars get the same kind of random misfires that go on the different cylinders (cause we are using vvti coils and obd2 I thought it was a good place to start)
Some have said its the coils, and others have said its the wires coming off of the coil to the other cylinders.. so check your plug wires if they are the stock ones I would replace them.
I would also double check on the spark plug gap it can be picky about that.
For another person it was a leaky injector but misfire code on only 2 cylinders.

Also I would double check the connectors on the 3 coils and make sure they still have the locking tabs. sometimes when these break the vibrations alone can cause weird ignition issues.

BuffNStuff

I bought brand new is300 coils, gapped my plugs down to .024, and I have not removed my EGR.

ashtray

iTrader: (12)

Hey Buff...what injectors are you running? Did you have to swap out your lower runners or are you on the stock ones if so what injectors...

187

So the dashpot was not even close to being set, I set it to 2200 which is still low and it helped alot.

Likewise the throttle opener was not even close, so now i have a screw in there bumping up the idle to around 1100.

It works at 1100 but it wants to idle at like 16.0 -15.9 afr, as apposed to 14.7-15.5 at 650rpm. I'm going to up the dashpot and drop the idle tomorrow to see if it helps.

187

So spent a bunch of time on the car. Right now im set at about 15% throttle position at idle and idle at about 1100 rpms. As you will see (hear maybe) below the idle just goes up and down with the fuel. Im getting misfire codes I've never gotten before even though all I have done is move the tps back to where it was and adjust the idle up. I tired adjusting the tps to 1.17% today and all it did was idle and as soon as you gave it any gas it would miss on every cylinder and would not rev past 2k. Set it back into the notches on the tps and set it as mentioned above. It seems to idle high enough to catch itself but the missing isn't right and the afr just bounces around at idle. The only other thing I can think to do it cut the slots to get in between 11% tp and 1.17 % TP. Idk what a stock supra tp% is and can't seem to find it.

But at 1.17% throttle the throttle blade was moving but the ecu wasn't seeing the movement at the tps because it was to low and not making contact with the "prongs" that move the tps from the inside. That or the voltage was too high.

Any suggestions?





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Ali SC3

iTrader: (10)

at 15% it can't be in the idle position can it? as in if you put the timing jumper in you wouldn't hear a change in sound. likely you have gone too far at 1100 rpm's. the range where you can increase the idle and still be at a low tps% is very very small. its more likely around 900 rpm's or so if even that.

I would guess at that position the ecu thinks you are still revving slightly which is why its not consistent where it will idle. you don't want it so low that its not touching, the prongs for the throttle blade should be resting on the tps plastic arms or just a hair past that where they are pushing on it slightly. that area is where it needs to be. if its way past that and you don't get the jumper sound you are way too far. if you get the jumper sound I think you are still good.

187

My fathers toyota v6 was at like 16% tp at idle, but it's a weird motor so idk. I can't get the change because the idle is to high for sure, but if i try to bring it to 900 it will force the idle down to 650. Basically i have it set to 11% tp then move the plate up to 16% using the screw on the back. Atleast this way it doesn't die when driving and coming to a stop. i can get it to idle great without touching the screw and stay at 11% but then it will go silly rich on the rev down and die.

Ali SC3

iTrader: (10)

you bring it to 900, it will force it to 650. then repeat increasing the screw going in painfully slow increments. after 1-2 tries it will stay at 900 rpm. its literally a quarter turn back from 1100 rpm. you guys are going past it or not far enough.

the problem is if you go too far, the idle seems great but since its too high and the idl switch isn't engaged )jumper doesn't make a change in sound), it will not drive correctly, and it will not cut out fuel on deceleration above 1500rpm's or above what rpm the ecu normally does it. this will result in over fueling and misfires.

If you got it to 1100 and to stay there that means the IACV is already maxed out in the lowest position. now just move it to 900. if you move it past 900, the IACV will open up more and you might be turning it alot.
What you want is the IACV in the lowest position and 900. you get what I am saying at all? you are a turn or so too far if you are at 1100.
the first few turns max out the IACV where it will still try to get to 650, but the next turn should keep the idle where it is after that 8-900. then another turn will go higher like 1100.
Also don't take turns literally it may be a half or quarter turn everyone is different.

Even if you find the sweet spot there is no guarantee that the tps will even set to the right position but any cracking of the throttle should help if you can squeeze a little out.

I might have to look at this again I didn't think the tps was such an issue.
it does not matter as much the position the throttle body is at, but the tps position matters greatly to the ecu.
also set the tps after the throttle screw as moving the throttle screw moves the tps there is no point setting it before.

187

Yeah the screw is crazy sensitive, i don't think i will be able to get it down much lower but i can try. Really i need a target throttle %, but even then it will still be searching and off and rich out. There seems to be no hint of an improvement either way which is quite frustrating.

Also the tp at wot might help, mine only goes to like 78 when its supposed to be 90?