LTFT 18-20 when idling

[GolsP5M32.5L]

2017 Mazda 3 2.5l sedan. LTFT all sudden running high. No codes. RPM at idle 500-730. I do have a scanner rand I can post more numbers if wanted.

 

[concept]

A significant increase in STFT and LTFT can be caused by:

• Unmeasured air is entering the engine due to a vacuum leak (higher fuel trim at idle, but less at higher RPMs)
• Incorrectly reporting sensors (dirty MAF reporting less airflow)
• Dirty or blocked fuel injectors

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Rich Fuel Trim - High Fuel Adjustment​

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A significant decrease in STFT and LTFT can be caused by:

• Restricted airflow to the combustion chamber (block exhaust or catalytic converter)
• Leaky fuel injectors
• Incorrectly reporting sensors

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When using LTFT and STFT for troubleshooting, then the fuel trim must be checked in a number of conditions:

• Cold/Warm engine
• Idle, low and high RPM
• No load, high load (heavy acceleration while driving)

 

[GolsP5M32.5L]

Cleaned the MAF. Fuel injectors also. Thinking it might be the PCV causing it. Not sure but was told to get to it have to take out the throttle body,Intake manifold and some wiring. With doing that I’d have to replace Gaskets and the cost starts to rise. I took the starter out and I can feel the PCV valve and it has a little wobble to it. At the angle I’m at I’m not sure if I can get a good enough hand on it to replace it tho. Reason I’m saying PCV is I may have damaged it putting in Oil Catch Can. My dumbass had a little too much to drink when doing it

 

[concept]

Do you know what the vacuum pressure is at idle compared to what it was or should be?

 

[GolsP5M32.5L]

I’ll get back to you in a couple hours. I’m up dating my scanner and left it at work