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Discussion Starter · #1 ·
Hi guys.
Ive had a few issues with the 35 post tune.
Its been back to a tuner here in Sydney a few times now and he hasnt been able to get to the bottom of it (whether he could be bothered or not is another thing).
Mods: Ecutek tune and TCM tune with injectors, catless downpipes and akra exhaust.
Symptoms: fluctuating idle - as though its about to stall. Usually only when temp reaches operating temperature.
Video was too large to attached but the data log is attached

Any insight would be most appreciated.

Many thanks
 

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Downunder,

I too have been having the same issue with my 17. I have Xona Greens, Injectors, Dp's and all the other normal stuff. And now, just two days ago, my car won't start. :dunno: I changed O2 sensors and fuel pumps and it still had idle issues. Now as a mentioned, it won't start at all. My next thought is maybe bad injectors... Who knows, I just want to get it sorted out!!!!

So, I'm trying to plan a way to get the car to Cicio's team in GA to get it sorted and retuned. Sorry, not much help, just letting you know I appear to be in the same boat as you.

Good Luck, and if/when I find the issue I'll post the findings.
 

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I have the same issue with my 2012. The idle drops and it rattles the bellhousing. Very irritating. Only when warm as well.
 

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Hi guys.
Ive had a few issues with the 35 post tune.
Its been back to a tuner here in Sydney a few times now and he hasnt been able to get to the bottom of it (whether he could be bothered or not is another thing).
Mods: Ecutek tune and TCM tune with injectors, catless downpipes and akra exhaust.
Symptoms: fluctuating idle - as though its about to stall. Usually only when temp reaches operating temperature.
Video was too large to attached but the data log is attached

Any insight would be most appreciated.

Many thanks
Do you have a fuel pressure monitor installed?

My car had these exact symptoms after a tune, where the fuel pressure monitor had been connected to bank 2 (in the tune) by my tuner instead of bank 1.
 

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Discussion Starter · #5 ·
Do you have a fuel pressure monitor installed?

My car had these exact symptoms after a tune, where the fuel pressure monitor had been connected to bank 2 (in the tune) by my tuner instead of bank 1.
Not sure Slim. Purchased the car with mods on it and the previous seller was very cryptic about what was done. Tune was rubbish so had to have it retuned, but even that has been questionable at best.

How can I check to see if it has the fuel pressure monitor installed?
 

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Discussion Starter · #6 ·
Its a shame that others are facing the same issue.

Hopefully we can find a resolution ASAP.

Is someone able to interpret the data log?
 

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Is the car throwing any codes? Another way you can have your logs reviewed is by uploading them to datazap.me

The photo that`s attached is my fuel pressure monitor on the rear of the motor.

I would be surprised if it is this causing the problems but you never know.

If it`s not the tune it may be a vacuum leak, MAF sensor covered in oil from the air filters or primary o2 sensor.

If you have the EcuTek cable and dongle check for DTC`s first .
 

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Discussion Starter · #8 ·
Is the car throwing any codes? Another way you can have your logs reviewed is by uploading them to datazap.me

The photo that`s attached is my fuel pressure monitor on the rear of the motor.

I would be surprised if it is this causing the problems but you never know.

If it`s not the tune it may be a vacuum leak, MAF sensor covered in oil from the air filters or primary o2 sensor.

If you have the EcuTek cable and dongle check for DTC`s first .
Thanks Slim.
No codes and DTCs are all good on ecutek.
Good advice RE vac, MAF and O2. Will clean out the MAF sensors and check for vac leaks then go from there.
Also checking out datazap.
Ive seen logs interpreted here every now and then so thought someone could chime in.
 

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GuiTaR
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You are very lean on both banks for that entire log (up to 20:1 in some places). If it's good when it's cold, but poor when it's warm, it just looks like the tuner needs to add a touch more fuel at higher coolant temps. Is Precision tuning this?
 

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Discussion Starter · #11 ·
You are very lean on both banks for that entire log (up to 20:1 in some places). If it's good when it's cold, but poor when it's warm, it just looks like the tuner needs to add a touch more fuel at higher coolant temps. Is Precision tuning this?
This is what the tuner said to what you mentioned above:

Engines will only run at 20:1 AFRs on overrun (ie when your off throttle on decel and engine braking) and its actually leaner than that (there is no fuel being injected whatsoever on overrun generally, 20:1 is just sensor limits for logging purposes). Under any form of attempted load at those AFRs the engine will basically stall. The trim issue was more the ECU hunting around target for some reason under certain conditions, everywhere else in the log things were fine and as they should be.
 

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GuiTaR
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Interesting. They are professionals so I wouldn't go against what they are saying.

What's surprising to me is the fact that, even though I can see it's hunting, I would've thought it would at least richen up at some point for a moment. It barely ever gets to stoich.

What size injectors do you have?

Is it possible there is a vacuum leak in a hose off the manifold that only presents itself when it's warm inside the engine bay?

Sent from my CPH1701 using Tapatalk

 

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Interesting. They are professionals so I wouldn't go against what they are saying. What's surprising to me is the fact that, even though I can see it's hunting, I would've thought it would at least richen up at some point for a moment. It barely ever gets to stoich. What size injectors do you have? Is it possible there is a vacuum leak in a hose off the manifold that only presents itself when it's warm inside the engine bay? Sent from my CPH1701 using Tapatalk
What`s your opinion on the primary O2 sensors/ECU not being able to compensate while running lean, could this be the cause? Maybe they were damaged while installing new downpipes?

Very strange though no CEL or DTC`s?
 

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GuiTaR
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If MRT were aware of GTR's, they would know they actually go to 30:1 on overrun.

I can see that the long term fuel trims are constantly adding 10% fuel on both banks for that entire log. Short term fuel trims, as the car hunts, go from 100 right up to 120 (adding 20% on top of the long term's 10%). This really seems like MRT need to at least give you an updated tune (at least just to test warm idle) so that you can flash it on to test.

I would need to see what a cold idle log looks like to see what the O2 sensors are doing. If this car behaves well when cold, and at higher load situations, I would not think it's the O2 sensors. The ECU is definitely not able to compensate enough since it's STFT are going up to 120.

My preference would be for MRT to modify your tune, which should only really take a few minutes for them, and send you the file to flash onto your ECU. Then you could go from there....

P.S. If you don't know the size of your injectors, there would be a bit of difficulty for MRT to get it right.
 

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Discussion Starter · #15 ·
Thanks for the feedback guys.
It went into the workshop and the tuner tweaked fuel trims.
The problem seems to have been resolved. Thanks to you all who chimed in. Most appreciated ☺
 

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Update,

I sent the car to Cicio Performance North. Jan and his team immediately figured out my issues.

Primary problem was a faulty MAP Sensor. Secondary issues centered around some O-rings on a brand new Visconti Fuel Basket and some re-grounding of the wiring harness.

After this was fixed, Taylor re-tuned the ECU and TCM and I'm back whole again. Car feels fantastic!!! I think it made somewhere around 830/630ish on Map #3. Jan may chime in on that...

The trans shifts soooo much cleaner and firmer with the new tune!! I haven't had a chance to get some Draggy data, but the car feels stronger than my last tune.

I would recommend to anyone looking for a top shelf shop and true professionals to give Jan and his team a call. I was a small job, but they made me feel like a BIG customer!!

If/when I decide to take the next step, there will be only one place my GTR will go, Cicio Performance!!!!!
 
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