Multiple Cylinder Missfire, w/knock code

Thraxbert

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OP:

Show us a picture of your MAP, MAF, and IAT sensors. Are they oriented in the correct direction? Secured tightly? Still have all the right gaskets and o-rings? For example, the MAF sensor has o-rings that can come off, if not seated properly, in the charge pipe which would cause a boost leak and lean condition.

YOUR MAF
This is right after the airbox/filter, AKA the "long needle" sensor you reinsert to an aftermarket intake. Most people think this is an IAT, including some of the vendors making intakes, but it is not. It's the MAF sensor.

1634230780410.png


YOUR IAT
This screws into the charge pipe right before the throttle-body. Has a "star" shaped ring that can be unscrewed by hand. Some people think this is the MAF, but it is not. It is the IAT sensor.

1634230931225.png


YOUR MAP
There's a bundle of wires coming towards the front of the engine, along the centerline. It's right above the charge pipe not long before it curves into the intake manifold.

1634231121473.png


Are you tuned? And you ONLY have an exhaust and intake with no other mods?

On the intake: does this system require that you take the rubber o-ring/gasket from the stock intake pipe and transfer it to the HKS unit before clipping the intake back onto the turbo-charger sub-assembly?

1634231577861.png
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NewGuy

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OP:

Show us a picture of your MAP, MAF, and IAT sensors. Are they oriented in the correct direction? Secured tightly? Still have all the right gaskets and o-rings? For example, the MAF sensor has o-rings that can come off, if not seated properly, in the charge pipe which would cause a boost leak and lean condition.

YOUR MAF
This is right after the airbox/filter, AKA the "long needle" sensor you reinsert to an aftermarket intake. Most people think this is an IAT, including some of the vendors making intakes, but it is not. It's the MAF sensor.

1634230780410.png


YOUR IAT
This screws into the charge pipe right before the throttle-body. Has a "star" shaped ring that can be unscrewed by hand. Some people think this is the MAF, but it is not. It is the IAT sensor.

1634230931225.png


YOUR MAP
There's a bundle of wires coming towards the front of the engine, along the centerline. It's right above the charge pipe not long before it curves into the intake manifold.

1634231121473.png


Are you tuned? And you ONLY have an exhaust and intake with no other mods?

On the intake: does this system require that you take the rubber o-ring/gasket from the stock intake pipe and transfer it to the HKS unit before clipping the intake back onto the turbo-charger sub-assembly?

1634231577861.png
The dealer still has the car so I can't get pictures until I get my car back. The car is not tuned. my only mods are intake and exhaust.

Yes, the instructions required that I take the stock o-ring and place it into the new intake pipe. I remember doing that when I installed the intake.

*edit* I just realized that I'm not the OP lol. Sorry for hijacking your post @Deepseahooyah . Hopefully we can get a solution to our problem.
 

Thraxbert

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I won't lie, OP. I think you have a defective sensor or defective motor as a worst case. But it's not the damn mods. An exhaust and intake is not going to cause knocks and misfires. Worst case, you'd get a CEL in the range of P0170-P0175 which represent things like: uncorrectable fuel trim, too lean or rich in a given cylinder bank. Or maybe P0069 for unexpected barometric issues in the charge side.

Knock, misfires, that's a lot more serious and very unlikely to be caused by any of the mods you have.

Are you running the OEM 0W20 oil and racing on it? The 0W20 OEM oil is fine for day-to-day use, but it is optimized for US emissions standards compliance and not for race use. If you're truly doing roll racing in Mexico on this car, you should be running a quality 30-weight or even a 40-weight oil. And the weather is still pretty damn hot and humid in the border region. As I think about your case and your engine, I'm wondering if the oil is just thinning out on you and causing conditions that would lead to consumption and knock.

I'd be interested to see if your issue persisted with one of these oils:

Quaker State Full Synthetic (QSFS) 5W30
Quaker State Full Synthetic Euro (QSFSE) 5W40 (BMW LL-01 for B58)
RedLine Full Synthetic 10W40 (BMW LL-01 FE approved for B58)
Amsoil 10W40 Synthetic XLOQT-EA (conforms with Toyota SN (or better) spec
 

NewGuy

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I won't lie, OP. I think you have a defective sensor or defective motor as a worst case. But it's not the damn mods. An exhaust and intake is not going to cause knocks and misfires. Worst case, you'd get a CEL in the range of P0170-P0175 which represent things like: uncorrectable fuel trim, too lean or rich in a given cylinder bank. Or maybe P0069 for unexpected barometric issues in the charge side.

Knock, misfires, that's a lot more serious and very unlikely to be caused by any of the mods you have.

Are you running the OEM 0W20 oil and racing on it? The 0W20 OEM oil is fine for day-to-day use, but it is optimized for US emissions standards compliance and not for race use. If you're truly doing roll racing in Mexico on this car, you should be running a quality 30-weight or even a 40-weight oil. And the weather is still pretty damn hot and humid in the border region. As I think about your case and your engine, I'm wondering if the oil is just thinning out on you and causing conditions that would lead to consumption and knock.

I'd be interested to see if your issue persisted with one of these oils:

Quaker State Full Synthetic (QSFS) 5W30
Quaker State Full Synthetic Euro (QSFSE) 5W40 (BMW LL-01 for B58)
RedLine Full Synthetic 10W40 (BMW LL-01 FE approved for B58)
Amsoil 10W40 Synthetic XLOQT-EA (conforms with Toyota SN (or better) spec
I am running OEM 0w20 oil. I wouldn't say I'm racing on it but when I get a chance to drive I do go to Mexico and top out the car. I got the car a year ago and have 6xxx miles on it. I don't drive it a lot but when I get the chance, I do go to Mexico for some spirited driving.

*edit to add more info* I did previously bring in the car when it was bone stock to address and oil consumption issue. It was around 4300 miles when I brought it in. Don't recall if I already mentioned this in this thread.
 
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NewGuy

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Looks like they came to the conclusion that it could be a faulty spark plug. However, they do not have the tool to remove it so ima have to wait until they can borrow the tool or it comes in from a special order. Lmao!

told them to call me tomorrow if they donā€™t have and Iā€™ll go check with bmw to see if I can buy one.
 

Thraxbert

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But they already replaced bad plugs?
 

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But they already replaced bad plugs?
No lol

so per the advisor, the tech ran through all the checks and determined that it has to be a bad plug. Everyone else is good on the car.
 

Thraxbert

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1634264329682.png


??? are all the plugs bad?
 

NewGuy

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*UPDATE*

Talked to the service advisor yesterday. So after a week-ish of "trouble shooting" they decided to finally remove and replace the sparkplug. Keep in mind that I provided them with the 14mm thin wall socket because they didn't have one?

The tech made the change and test drove the car. He said the car is good but it seems to be "re-learning"? The tech left the battery unplugged over night and will plug it in to make sure the car is good to go. Should have the car back tomorrow since the tech is off today.

I just want to say that I'm never taking the car back to a dealership. I only took it in because I don't have a diagnostic tool to read the codes. I'm going to buy the tool so I can make my own repairs in the future.

They kept asking if my car was tuned- I thought they were able to tell if a car was tuned or not by reading the ecu logs? The car is not tuned and never has been tuned ?
 
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Deepseahooyah

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I won't lie, OP. I think you have a defective sensor or defective motor as a worst case. But it's not the damn mods. An exhaust and intake is not going to cause knocks and misfires. Worst case, you'd get a CEL in the range of P0170-P0175 which represent things like: uncorrectable fuel trim, too lean or rich in a given cylinder bank. Or maybe P0069 for unexpected barometric issues in the charge side.

Knock, misfires, that's a lot more serious and very unlikely to be caused by any of the mods you have.

Are you running the OEM 0W20 oil and racing on it? The 0W20 OEM oil is fine for day-to-day use, but it is optimized for US emissions standards compliance and not for race use. If you're truly doing roll racing in Mexico on this car, you should be running a quality 30-weight or even a 40-weight oil. And the weather is still pretty damn hot and humid in the border region. As I think about your case and your engine, I'm wondering if the oil is just thinning out on you and causing conditions that would lead to consumption and knock.

I'd be interested to see if your issue persisted with one of these oils:

Quaker State Full Synthetic (QSFS) 5W30
Quaker State Full Synthetic Euro (QSFSE) 5W40 (BMW LL-01 for B58)
RedLine Full Synthetic 10W40 (BMW LL-01 FE approved for B58)
Amsoil 10W40 Synthetic XLOQT-EA (conforms with Toyota SN (or better) spec
Thank you as I am the OP for this thread. I will update as of yesterday. Just got the car back from germain Toyota, Naples, FL.

they had the car for 2 days. I provided video proof of the misfire(recreated the situation for the shop foreman). He is dumbfounded, he test drove the car and was not able to recreate the symptoms, still showing a cylinder 1 misfire on the code storage in the ecu. They erase the code and nothing. Toyota technical is telling them unless the car has stock exhaust and factory air box. They will not help or diagnose any further. I am currently trying to find a person who has a factory airbox so I can reinstalled. I asked him if I could take him for drive he stayedā€Toyota will not allow thatā€. I stated to him the car needs to be driven like a Supra not in comfort mode. He stated ā€œTASā€ ā€œ will not allow technicians to drive aggressively or sport mode when doing there diagnostics.

I told him that is when it happens

the car is not tuned as it is a 02/21 build date
Modification are only hks intake, AWE track exhaust.

Drove it tonight and went to south of the border with some cars. Third run (check engine light came on and had a misfire) I donā€™t know which cylinder at the moment.

checked Maf, Iat, etc and all gaskets are in place.

I shut the car off for 20 mins or so, took around the block and no issues.

I am at a loss and need some deep guidance on this matter, truly love this car!
 
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Deepseahooyah

Deepseahooyah

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I won't lie, OP. I think you have a defective sensor or defective motor as a worst case. But it's not the damn mods. An exhaust and intake is not going to cause knocks and misfires. Worst case, you'd get a CEL in the range of P0170-P0175 which represent things like: uncorrectable fuel trim, too lean or rich in a given cylinder bank. Or maybe P0069 for unexpected barometric issues in the charge side.

Knock, misfires, that's a lot more serious and very unlikely to be caused by any of the mods you have.

Are you running the OEM 0W20 oil and racing on it? The 0W20 OEM oil is fine for day-to-day use, but it is optimized for US emissions standards compliance and not for race use. If you're truly doing roll racing in Mexico on this car, you should be running a quality 30-weight or even a 40-weight oil. And the weather is still pretty damn hot and humid in the border region. As I think about your case and your engine, I'm wondering if the oil is just thinning out on you and causing conditions that would lead to consumption and knock.

I'd be interested to see if your issue persisted with one of these oils:

Quaker State Full Synthetic (QSFS) 5W30
Quaker State Full Synthetic Euro (QSFSE) 5W40 (BMW LL-01 for B58)
RedLine Full Synthetic 10W40 (BMW LL-01 FE approved for B58)
Amsoil 10W40 Synthetic XLOQT-EA (conforms with Toyota SN (or better) spec
i will try and switch oil this weekend! Again thank you. This is the most information I have received, they refuse to give the codes the ecu are throwing, they say the car sends them to Toyota and ultimately bmw, when they hook it up.??ā€ā™‚
 
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Deepseahooyah

Deepseahooyah

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The dealer still has the car so I can't get pictures until I get my car back. The car is not tuned. my only mods are intake and exhaust.

Yes, the instructions required that I take the stock o-ring and place it into the new intake pipe. I remember doing that when I installed the intake.

*edit* I just realized that I'm not the OP lol. Sorry for hijacking your post @Deepseahooyah . Hopefully we can get a solution to our problem.
No problem man, this thread was for all of us. Dealing with Toyota is starting to be a complete nightmare. Check out resent post
 

NewGuy

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No problem man, this thread was for all of us. Dealing with Toyota is starting to be a complete nightmare. Check out resent post
No problem man, this thread was for all of us. Dealing with Toyota is starting to be a complete nightmare. Check out resent post
They finally decided to check the spark plug after Iā€™ve been telling them to do so. I got this text below so I hope that resolves the problem. I wanna say that this Saturday will be two weeks since theyā€™ve had the car. Iā€™ll also switch to a different oil. I figured Iā€™d give liquid Molly a try.
974952F1-5AEF-4C40-92E4-AC5EBA953F54.jpeg
 
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Deepseahooyah

Deepseahooyah

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They finally decided to check the spark plug after Iā€™ve been telling them to do so. I got this text below so I hope that resolves the problem. I wanna say that this Saturday will be two weeks since theyā€™ve had the car. Iā€™ll also switch to a different oil. I figured Iā€™d give liquid Molly a try.
974952F1-5AEF-4C40-92E4-AC5EBA953F54.jpeg
I wish you luck, they replaced cylinder 1 and 6 on my car and switch coils from 1 to 5 and vise versa
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