Builds my turbo build

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:bang: SAFC DOESN'T WORK! you can adjusted the AF but after couple min even sec it goes back to normal!:crybaby: plus p0100 code is there all the time!
 
:bang: SAFC DOESN'T WORK! you can adjusted the AF but after couple min even sec it goes back to normal!:crybaby: plus p0100 code is there all the time!

I think you are trying to adjust AFR during closed loop. If that is the case then the problem lies with your O2 sensors. During closed loop they rule. The ECU assumes that they are 100% and will always adjust to a predetermined value.
 
:bang: SAFC DOESN'T WORK! you can adjusted the AF but after couple min even sec it goes back to normal!:crybaby: plus p0100 code is there all the time!

Like I said, pita ptb and closed loop. You ain't gonna win that battle with the ECM. Better off running it without the o2's hooked up. May want turn up your fuel pressure or run the vac line straight off the turbo for rising rate with each psi of boost. That is if you're running a RRFPR. Otherwise, might want to think about using the AEM injector controller instead of the SAFC. Might want to up the size of your injectors also. Just a few thoughts...
 
I think you are trying to adjust AFR during closed loop. If that is the case then the problem lies with your O2 sensors. During closed loop they rule. The ECU assumes that they are 100% and will always adjust to a predetermined value.

yes i was trying to adjust my afr during closed loop,because that is my problem in closed loop 14.7 even under boost. when my truck hit the open loop my afr is 12.2 or lower. i dont use this truck for racing i just want some extra power.:frown:
My open loop is close to 2800 or 3000 rpm at half open throttle. Do you know any way to adjust the open loop? like maybe at 2600:meh:
 
Like I said, pita ptb and closed loop. You ain't gonna win that battle with the ECM. Better off running it without the o2's hooked up. May want turn up your fuel pressure or run the vac line straight off the turbo for rising rate with each psi of boost. That is if you're running a RRFPR. Otherwise, might want to think about using the AEM injector controller instead of the SAFC. Might want to up the size of your injectors also. Just a few thoughts...

:hhmm: well im in this boat now! so i need to find out the way to fix this issue but :bang::censor: im tired at this ****!

What about if i clean the MAF what can i use to clean it?
 
:hhmm: well im in this boat now! so i need to find out the way to fix this issue but :bang::censor: im tired at this ****!

What about if i clean the MAF what can i use to clean it?

Look at your data!

The truck is running lean

You wire in a controller to trick it into running properly

Then the ECU compensates and you are running lean again.

1. Because you were able to trick the ECU to get the proper AFR, the truck has the ability to properly fuel the engine.

2. Because after tricking the ECU it reverted back to the original AFR, the ECU is functioning and doing it's job.

The problem is that the ECU is targeting the wrong AFR. This is solely the responsibility of the O2 sensors. It's the readings from those sensors that sets up the target.

IMO you either have:

1. bad O2 sensors
2. aftermarket O2 sensors
3. a wiring problem in the main engine harness.

As I've posted before, IMO you have a core problem in the fueling system.
 
Look at your data!

The truck is running lean

You wire in a controller to trick it into running properly

Then the ECU compensates and you are running lean again.

1. Because you were able to trick the ECU to get the proper AFR, the truck has the ability to properly fuel the engine.

2. Because after tricking the ECU it reverted back to the original AFR, the ECU is functioning and doing it's job.

The problem is that the ECU is targeting the wrong AFR. This is solely the responsibility of the O2 sensors. It's the readings from those sensors that sets up the target.

IMO you either have:

1. bad O2 sensors
2. aftermarket O2 sensors
3. a wiring problem in the main engine harness.

As I've posted before, IMO you have a core problem in the fueling system.

If he's getting 14.7/1 or close in closed loop, wouldn't that idicate that everything is working properly with the o2's? The ECU should always target 14.7/1 anywhere in the closed loop range. The range is the problem. He's not getting open loop soon enough in the rpm range or air flow/psi range. Usually that happens when open loop is determined by throttle position instead of other factors like rpm/air flow.
lantank, aren't you running any forced induction? We need someone to chime in that is and also has a wide band. See where a typical SC truck hits open loop, at what boost, aprx throttle position, or rpm. This should tell us if throttle position is the determing factor. Also, the yota engineers may have thought some boost in closed loop isn't that big of deal. Most stock turbo cars will have some ptb because the motors are built for it. Especially with an auto trans. It will shift and drop rpm before, say 3-5psi in closed loop, runs up past, say 4K rpms, where it might cause engine damage. I'm just brainstroming here cause I'm not that familar with how the 80's ECU is programmed. But I'm pretty sure that the yota guys wouldn't have had a problem with 5psi @ 3000rpm. To get the motor to rev, you'd have to get in the throttle and hit open loop, drop AFR and let'r rev to red line @ full boost. At least that is how I have seen it with auto's and stock turbos.
I'd still do a through check of all your fuel components and connections. You may have a leaking connection in the tank so you're not getting the proper flow. I had a fuel line in the tank start leaking once and all the sudden my wide band went way lean and at idle you could hear the fuel spraying in the tank from the break in the line. Agian just something to check.
 
I believe the ECU slips into open loop based on a few factors, throttle position and engine load being the two biggies on the 5vz (and therefore maybe the 1fz).

Look man, you're not battling anything new here, you either need to tune around the ECU in closed loop, dumping in fuel in open loop to protect the engine during these high-boost, high-load times or you get a piggyback that will also intercept the O2 signals and let you tune to any AFR at any time or you go standalone.

Wringing performance out of an engine is a slippery slope of cost, time and tweaking.

If you want a piggyback that will let you put any AFR even in closed loop, the MAPECU2 is your one stop shop. Call Gadget at URD and talk wit him, he is the CDan of boosting Toyota trucks, or you could continue on rediscovering the wheel. Your choice!
 
Its great to see things moving forward with 1fzfe forced induction. note however that ive been running 10lbs of boost on my guage for a year now and the motor still hasn't exploded. not monitoring anything save engine temp and egt now. the narrow band wiring was even torn off my a pine tree i ran over (on my personal property) last fall so i dont even have that anymore. only mods besides the turbo were to rebuild the head, add a water jacket to the turbo (cooked the first oil cooled only turbo) put on a new gasket, make sure the supra pump is running and Go Go Go

if someone can show that more boost can be supported with little modification to the oe engine management ill turn up the boost too

my only complaint with my turbo set up is that under full boost climbing a steep hill fast and hard.... if i let off the gas completely, without letting off gradually, it will kill the motor. and it bugs me. i wish there was a fix for this one issue.
 
...my only complaint with my turbo set up is that under full boost climbing a steep hill fast and hard.... if i let off the gas completely, without letting off gradually, it will kill the motor. and it bugs me. i wish there was a fix for this one issue.

why is your motor killing when you let off the gas at Wide Open Throttle?
 
why is your motor killing when you let off the gas at Wide Open Throttle?

thought it still have much more Oxigen than fuel in the combustion chamber .. for a seg ..
 
my only complaint with my turbo set up is that under full boost climbing a steep hill fast and hard.... if i let off the gas completely, without letting off gradually, it will kill the motor. and it bugs me. i wish there was a fix for this one issue.

Dusty,

Did you ever fit a recirculating or dump blow off valve? Or none at all? I can't remember from your build.

Just thining out loud here - maybe the pressure in the pipes (if no BOV fitted) is causing some kind of stall/back pressure on the compressor which is slowing the air flow enough to stall the engine? At this time, theECU will be in open loop fully dumpng loads of fuel through the injectors.

Just a thought OK lol

:)

EDIT - if the compressor is being affected, then the turbine will also be slowing down, maybe causing resistance to the exhaust flow. Together causing enough problems to stall the engine???
 
Dusty,

Did you ever fit a recirculating or dump blow off valve? Or none at all? I can't remember from your build.

Just thining out loud here - maybe the pressure in the pipes (if no BOV fitted) is causing some kind of stall/back pressure on the compressor which is slowing the air flow enough to stall the engine? At this time, theECU will be in open loop fully dumpng loads of fuel through the injectors.

Just a thought OK lol

:)

EDIT - if the compressor is being affected, then the turbine will also be slowing down, maybe causing resistance to the exhaust flow. Together causing enough problems to stall the engine???

good thought
but i have a volvo BOV. i didn't have the problem as much at 6psi but at 10lbs of boost it happens at leaste half the time. sounds like its running out of gas and half the time it just dies. if i give it a little gas i can save the shut down but when im in these hairy situations i often need to sop RIGHT NOW. so i need to let off the gas completely and not risk it.

perhaps a bigger BOV?
 
good thought
but i have a volvo BOV. i didn't have the problem as much at 6psi but at 10lbs of boost it happens at leaste half the time. sounds like its running out of gas and half the time it just dies. if i give it a little gas i can save the shut down but when im in these hairy situations i often need to sop RIGHT NOW. so i need to let off the gas completely and not risk it.

perhaps a bigger BOV?

Do you have the BOV before or after you MAF? I think you would want it before the MAF: Intercooler -> BOV -> MAF -> TB -> Intake mani. that way your MAF is still seeing the same pressure/vac as the mani. If you've got it after the MAF, its not gonna read the same when the BOV is open. If that's not the problem look to a bigger BOV.
 
Do you have the BOV before or after you MAF? I think you would want it before the MAF: Intercooler -> BOV -> MAF -> TB -> Intake mani. that way your MAF is still seeing the same pressure/vac as the mani. If you've got it after the MAF, its not gonna read the same when the BOV is open. If that's not the problem look to a bigger BOV.

it has been so long since i looked hard at my turbo that i cant even remember how i the parts are in order. i will take a good look and consider. but not today. in 2 hours i head out to calico california to wheel the bitchin trails out there in the desert. the truck runs and performs so good nowadays i only open the hood to change the oil and then i close it again for another 3 months. and seeing as she is a wheeler only there is only a couple hundred miles max between oil changes. damn these yotas are nice

sorry to hijak
 
From my testing closed loop is to about 17lbs of air. All during the time you are at 14.7AFR. Then as you transition into open loop the AFR is 12.3. When you get to 99% calculated load, which is about 22lbs of air, things go crazy rich to about 8.6 AFR.

Dusty, your problem might be too small a BOV or too restricted on the recirculation.

When you let off the gas abruptly while under full boost the throttle plate slams shut and that loads up the compressor side of things stalling the compressor. That stall transfers over to the turbine restricting the exhaust side of the engine producing a lot of back pressure. That back pressure will kill the engine.

The idea of the BOV is to allow the turbo to free spin during those times so it doesn't interfere with normal operation, The fact that it spools that much fast if you get on it soon after is a plus.

This condition can also give you a hard brake pedal riaght after letting off the gas. Do you have that?
 

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