Roddicks 5Sgte St162

[Trev]

I'd say that you are getting fuel cut, this is bad when boosting as the engine has a lean out, suggest getting a GTE ecu and a FCD at the very least or an aftermarket ecu.

[roids70]

so are you saying its cutting the fuel from the engine when its lean or am i not understanding it very well

[Des]

so are you saying its cutting the fuel from the engine when its lean or am i not understanding it very well

The ecu would be cutting fuel and making it lean out. Fuel cut defender or a GTE ecu like trev said would solve it.

[Trev]

The ecu would be cutting fuel and making it lean out. Fuel cut defender or a GTE ecu like trev said would solve it.

 

I would be getting the FCD with the GTE ecu as the GTE ecu is supposed to have cut at like 10-11psi, I suggested the GTE ecu for the fuel maps.

[roids70]

eyah but it wasn't doing it on boost,, I'm hoping thats what you mean, it was missing while trying to take off at low rpm witch it didn't do till i was taking it back in, 4 times i hit boost it hit boost haply at 10psi and it held it like it was capable of taking boost, i could be wrong but i would expect the rising rate fuel reg to stop that, could be wrong, not to good with engine electrics and stuff like that

Edited November 13, 2010 by roids70

[Trev]

eyah but it wasn't doing it on boost,, I'm hoping thats what you mean, it was missing while trying to take off at low rpm witch it didn't do till i was taking it back in, 4 times i hit boost it hit boost haply at 10psi and it held it like it was capable of taking boost, i could be wrong but i would expect the rising rate fuel reg to stop that, could be wrong, not to good with engine electrics and stuff like that

 

I took it as you hit 10psi and the car started to cough and splutter.

 

Might of just been the AFM plug, check your spark plugs and see how it is running.

 

Fuel pressure doesn't stop fuel cut, the ecu detects engine boost/air intake levels (to be honest, I don't know if the n/a ecu is capable of this) and stops the injectors firing.

 

Brad (beerhead) is probably the wisest S series member on here so he could explain it better.

[roids70]

I took it as you hit 10psi and the car started to cough and splutter.

 

Might of just been the AFM plug, check your spark plugs and see how it is running.

 

Fuel pressure doesn't stop fuel cut, the ecu detects engine boost/air intake levels (to be honest, I don't know if the n/a ecu is capable of this) and stops the injectors firing.

 

Brad (beerhead) is probably the wisest S series member on here so he could explain it better.

 

 

yeah if you see in the vid i posted, as i took off when i left the last corner it pretty much died a couple of times befor it actually took off properly, but yeah like i said befor it hit 10 psi without any problem, didn't cough didnt die, just took off, I'm going to try and get another vid so i can show people its hitting 10 without a problem,

 

i will also be looking at getting a 165 gte ecu depending on price as they are hard to come by since they are imports to aus, i have got one i can get from switzerland but i think I'm going to need wireing, boost pressure switch, knock sensor, and AFM, and possibly a few other things depending on what the gt4 has that i don't have, so it could cost a lot, and I'm not one for alot of money hence y i don't have an aftermarket ecu cause i clearly can't afford it.

[beerhead]

Yeah 10psi on a stock AFM will definitely hit fuel cut which is when the AFM is at 100%. You could get it working better by putting in larger volume injectors and then increasing the tension of the air flow meter spring, to make the ecu progress slower into the map. A wideband with a datalogger would be ideal to get everything spot on, but with persistence good results can be had. An old fart I know does this to supercharge motors with stock atmo AFM ecus. I did the same adjustment trick with a 3SFE AFM on my 20V, people all say they won't rev out without an oxygen sensor, which my setup is currently missing, and it'll bounce off the limiter very happily.

[roids70]

Yeah 10psi on a stock AFM will definitely hit fuel cut which is when the AFM is at 100%. You could get it working better by putting in larger volume injectors and then increasing the tension of the air flow meter spring, to make the ecu progress slower into the map. A wideband with a datalogger would be ideal to get everything spot on, but with persistence good results can be had. An old fart I know does this to supercharge motors with stock atmo AFM ecus. I did the same adjustment trick with a 3SFE AFM on my 20V, people all say they won't rev out without an oxygen sensor, which my setup is currently missing, and it'll bounce off the limiter very happily.

 

 

 

the thing is though it wasn't hitting fuel cut i could of hit limiter befor it hit fuel cut. witch is what I'm really puzzled about because you've explained that it should hit fuel cut. which now after doing some research i understand it better and i myself beleive it should have it fuel cut. one stage as i was driving it was at about 6,500rpm and it wanted to keep going but i decided to change gears. it was only when i took off from a still position that it died a few times, one thing i do know for sure is the oxysensor on the 3sge and gte are only being used when cruising to help with fuel economy and anothing thing i do know is that when cruising my timing gets advanced out to 30 degrees and on load it goes back to 12 - 15 and at idle its about 8-10 advanced, now apparently 30 degrees is not good for me??? just what i've been told, i did know about the tension of a AFM i read it on some supra site and was interested in doing it but i would rather have a spare AFM first and try it, and i also have 550cc denzo's ready to put in the car when i was gunna get an aftermarket ecu

[beerhead]

I'm pretty sure the oxy sensor will adjust the trim of the ecu at low RPM points too. Was the ecu reset after putting the turbo gear on it? Make sure the idle control is working properly, though those the gen1 may just be a wax pellet like a bigport 4AGE. I wonder if the ecu has a closed loop at lower RPM autotune when you turn the ecu on after a reset like most others around? Might be worth trying turn everything on in the car, lights, AC/ Heater, dimister, and jiggle the power steering as you first fire the car up so that the ecu sets a new baseline for the map.

 

If you want to fiddle with the AFM get a paint pen and put a dot somewhere on the big cog you spin around that adjusts the tension, then on on the body of the unit, that way you can easily set it back to your starting point if things go sour.

 

Depending on what gear you were in you may not have hit the fuel cut yet, but I think it'll happen up in the top end.

 

I'd retard the base timing a touch too, 5-7 degree's base will keep things happier until you get an aftermarket ECU.

[roids70]

I'm pretty sure the oxy sensor will adjust the trim of the ecu at low RPM points too. Was the ecu reset after putting the turbo gear on it? Make sure the idle control is working properly, though those the gen1 may just be a wax pellet like a bigport 4AGE. I wonder if the ecu has a closed loop at lower RPM autotune when you turn the ecu on after a reset like most others around? Might be worth trying turn everything on in the car, lights, AC/ Heater, dimister, and jiggle the power steering as you first fire the car up so that the ecu sets a new baseline for the map.

 

If you want to fiddle with the AFM get a paint pen and put a dot somewhere on the big cog you spin around that adjusts the tension, then on on the body of the unit, that way you can easily set it back to your starting point if things go sour.

 

Depending on what gear you were in you may not have hit the fuel cut yet, but I think it'll happen up in the top end.

 

I'd retard the base timing a touch too, 5-7 degree's base will keep things happier until you get an aftermarket ECU.

 

 

the ecu has been reset many times mainly cause i've had the ecu out a few timesand the battery out. i knew the idle controll is working perfectly cause i have to steer quite excessivly to get out of home lol its a bit of a challenge. what you mean by wax pellet? and how can you tell an ecu has a closed loop at lower RPM?

[beerhead]

The wax pellet idle control on the early toyota's works like a thermostat on an air bypass to pick up the revs when the motors cold, and shuts with warm coolant as the motor heats up (though most are broken these days).

 

If there's a 3 wire plug on a small plastic box on the side of the throttle body it'll have electronic idle control, take the 2 screws out of the solenoid body and check if the actuator still spins smoothly and easily. If its crusty pull it off and feed it carby cleaner or kero until it's smooth to moove with your fingers.

 

Not sure about the gen1 ecu and closed loop, but most ecu's do after the early 80's do, so I'd suggest trying to reset the ecu again and load up the motor like I was talking about to see if it changes its behaviour. BTW is the oxygen sensor any good? Might be worth checking the error codes to make sure it's not the problem, or the ecu reset will do nothing but put it in the base map.

 

The other thing that's worth doing is to take the cover off the AFM and at idle push the needle back and forwards to pick a different part of the map, not sure if you've played with carby motors in the past and heard the engine note change when you adjust the idle screw, but you'll hear the motor stumble if there's too little fuel. I'd guess a bit of extra fuel at idle would be good, 200cc larger motor now, so that's 10% more fuel needed from the get go. I'd undo the bolt that sets the base position of the needle and try moving it forwards the same distance that fiddling with the needle when the motor was running made the motor sound the happiest. Once again scratch a mark or use a paint pen so you know your starting point when you do these things, just in case..

[roids70]

i think it might have had wax pellet at one stage but now broken, the only thing i got there on the side of the throttle body is the throttle positioning sensor u nless that does the same thing?

 

the oxy sensor is pretty much brand new, i have the error code come up on me a ahile back when it was n/a so i bought a new oxy sensor

[roids70]

got another update,

 

exhaust is plumbed took for another drive, still have no BOV but it flutters very loud, still goes well on the standard ecu, still waiting for my other ecu atm, but thats not a problem.

also got a spare engine loom today so i can re do the pins to fit the gt4 ecu, will get a vid soon cause i also need a new batter cause the one thats in it is fubared

 

Cheers Sean

[roids70]

update......

 

got a vid of the car running on the 3sge ecu, didn't end up taking it for a drive had no time in the end

sorry about the gibberish had a hard day at work that day

 

 

 

 

and as of today i have the 5sgte running ...... only running..... off the gt4 ecu,

on later inspection the ecu threw out 34 as a code

witch was turbo pressure signal, cause i don't have a boost pressure sensor, just need to think if there is a way either bypass it or if a have to buy a universal one