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blue62 · 09-25-2022, 06:01 AM

you would need more information such as.
Fuel trims compared to MAF values.
Throttle position compared to MAF values.
How the engine runs at idle.
How the engine runs at 1800-2500 RPM vrs idle.
O2 sensor signal at idle and midrange.

To make an assumption based on a single data point is not good diagnostics.

You could have those MAF values for many reasons.
Like aging sensor
Dirty sensor
Dirty air filter

If you think you have a vacuum leak there are other ways to determine that.
Like using a vacuum gauge to do a vacuum test.
A smoke test
How the engine idles vrs how it runs at 1800-2500 RPM

09-25-2022, 06:01 AM	#2
blue62 Registered User Join Date: Aug 2018 Location: Woodland Wa Posts: 1,304	you would need more information such as. Fuel trims compared to MAF values. Throttle position compared to MAF values. How the engine runs at idle. How the engine runs at 1800-2500 RPM vrs idle. O2 sensor signal at idle and midrange. To make an assumption based on a single data point is not good diagnostics. You could have those MAF values for many reasons. Like aging sensor Dirty sensor Dirty air filter If you think you have a vacuum leak there are other ways to determine that. Like using a vacuum gauge to do a vacuum test. A smoke test How the engine idles vrs how it runs at 1800-2500 RPM Last edited by blue62; 09-25-2022 at 06:04 AM.