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2001 Lexus is300 (turbonetics kit)
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Discussion Starter · #1 ·
Ok I’m going to try and summarize this as best as possible because it’s a lot of info.

My cars a 2001 2jzge na-t semi forged Internals ( Gte rods Arias pistons)
Car has a base tune/conservative through greddy e-manage, and was running fine.
I started getting an issue with idle/throttle.
I changed the tps sensor and the idle improved but then the problem came back. Problem being that the car would start losing throttle input as I pushed the accelerator pedal more and more til it would die. so after that I did the apps sensor and improved again even my braking felt better and then the same thing happened. So then i changed the plugs wires did an oil change OEM oil/filter, cleaned the throttle body etc…. connected everything and now the car the WONT START. At this point I remember that I was having issues with the fuel gauge at times reading full and then getting empty out of nowhere or also it would struggle and then go when accelerating so figured maybe it’s the pump and when I got in to swap it, it already was swapped for a walbro 250. I installed the aem 340 pump since I already bought it. Same thing…. would not turn over. I bought a new battery next to cancel that out I checked my fuses and the efi one blew. I switched it and then the car would turn over then rattle/knock and turn off I the realized my key was not getting recognized the security light was flashing so i programmed my key and still the same thing l!
I’m contemplating on getting a new throttle body unit???


anyone please help
 

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I think the best thing is to start at the beginning. First the car wont start unless the key is programmed so if it starts with your key there is something else wrong with your security light. This might be related to your efi fuse. Once you get your security light and key sorted then work on getting the engine going.
 

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Then your next step would be to keep it running. Id get a scan tool and see why it dies could be no oil pressure, these cars will die if there's no oil pressure I believe. It could also be a clogged fuel filter that restricts flow so it dies after a couple seconds. Get a scan tool and look at your data as it runs also make sure there are no codes stored.
 

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are your injectors stock? sounds like a fuel cut issue if it doesn't stay running.....lastly...unless you have a blackbox installed too, that emangle and your stock ECU is going to fight each other.
 

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2001 Lexus is300 (turbonetics kit)
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Discussion Starter · #10 ·
Online it’s (IAC) same thing I guess throttle control motor….,idle air control valve….. Autozone has it for 140 lifetime warranty can’t argue with that 🤷🏽‍♂️
 

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Discussion Starter · #11 · (Edited)
are your injectors stock? sounds like a fuel cut issue if it doesn't stay running.....lastly...unless you have a blackbox installed too, that emangle and your stock ECU is going to fight each other.
“are your injectors stock?”
I believe so 420cc .
“sounds like a fuel cut issue if it doesn't stay running”
Yea that’s that I was thinking
the car was tuned and was running fine until recently when that throttle input issue started which then led to me not being able to get the car running.
I think I’m gonna buy the iac for now see it that works or changes anything……
Also was thinking maybe 02 sensors…..
 

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“are your injectors stock?”
I believe so 420cc .
“sounds like a fuel cut issue if it doesn't stay running”
Yea that’s that I was thinking
the car was tuned and was running fine until recently when that throttle input issue started which then led to me not being able to get the car running.
I think I’m gonna buy the iac for now see it that works or changes anything……
Also was thinking maybe 02 sensors…..
If any 02 sensor, it will be the primary sensor only. Secondary will not cause the car to die. Is the fuel pump turning on when you start the car? Did you check if the injectors are still providing fuel? Also try cleaning the MAF to help it reads better.
 

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Online it’s (IAC) same thing I guess throttle control motor….,idle air control valve….. Autozone has it for 140 lifetime warranty can’t argue with that 🤷🏽‍♂️
VVTi 2JZ ‘s do not have an iacv. It’s got throttle control motor. Which is what your p1128 Toyota error is telling you may be the problem. Check the wires going to the throttle body. Should have tps 1&2, apps 1&2, throttle motor control, and the throttle clutch wires. Bet the issue lies with one of them wires.

Do you hear the throttle motor whine when you turn the key to “on” - don’t start the engine, just “on”?


remember that I was having issues with the fuel gauge at times reading full and then getting empty out of nowhere
Yeah, that’s a well-documented issue on MAF-altered turbo cars. It does not have anything to do with your current problem.
 

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Discussion Starter · #15 ·
VVTi 2JZ ‘s do not have an iacv. It’s got throttle control motor. Which is what your p1128 Toyota error is telling you may be the problem. Check the wires going to the throttle body. Should have tps 1&2, apps 1&2, throttle motor control, and the throttle clutch wires. Bet the issue lies with one of them wires.

Do you hear the throttle motor whine when you turn the key to “on” - don’t start the engine, just “on”?




Yeah, that’s a well-documented issue on MAF-altered turbo cars. It does not have anything to do with your current problem.

I’m just reffering to what it says on the auto parts websites. It’s labeled as idle air control there. But yea it makes a buzzing sound I replaced it and installed a new one and the same thing. Won’t turn over.

I guess ima look over the fuel pump installment again.

could it be that it needs to be reprogrammed even though the key works (security light goes away)
 
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