Manifold Absolute Pressure reading

[soggy]

I have a 2017 chevy Sonic with 56000km/35000mi which the engine started to get generally noisier plus a tapping sound and started using a lot more gas. Took it in to pull codes recieved
p1101, p01711. They said the intake filter was blocked and changed it. Didnt change a thing for the issue.

I've obtained an obd2 reader and reading that these cars always have vacuum leak issues, I decided check the MAP.

The question I have is what should the idle reading be?

Mine fluctuates between 5.8psi - 7.3psi and atmospheric is 17.6.

The tapping sound seems to be coming from around the intake manifold, but it could just be echo coming from somewhere else. The PCV which is supposed to be a common failure is fine so the cam cover and gaskets should be ok. Vacuum hoses are good so is the hose coming from the airbox.

 

[calebsullivan3]

I hate to respond to your question and not be able to answer it but participation on the forum seems low these days. I have a similar question as you that is left hanging in another thread.

Anyway, while I’m not sure what the manifold reading is “supposed” to be, I recently invested in a vacuum gauge and read mine after modding the check valve on the manifold and doing some other vacuum leak work. The reading I got was around 10inHg.

Are you still having the issues you described in the OP? If not, what was the fix?

 

[skurtov]

There's a pressure sensor on the left top of the manifold. Juts out. Replace it, and see if that fixes it.

 

[BigLee]

The tapping sound could the purge valve on top of the intake manifold.
Common for them to get loud as they age.
Unplug it while at idle to see if the noise goes away.

 

[soggy]

it was the purge valve.
thanks for the suggestions.