Vacuum test on my car: your opinions please.

fdjizm

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Sup fellas, Well all this catalytic converter talk got me a bit paranoid, so I picked up a vacuum gauge, hooked it up to the line that goes to the fuel pressure regulator line with a 3 way fitting (in between).

In the video I slowly rise to about 2500rpm and hold it there best I can (my tune just keeps rising) it does go as far as probably 3200rpm in the video, does this reading look like it's in good shape?

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Edit *new video below* (changed tune so I can hold a steady RPM)
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Bad news, good news, I appreciate it all thanks fellas, I count on your wisdom :beerdrink:
I have read on what to look for, it looks OK to me but I rather have a 2nd opinion to be sure.
 
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TexasBlownV8

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What are you trying to solve or figure out? The condition of the cats? Help us out here!

The vac looks normal.
 

fdjizm

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I am uploading a better video, had to switch my tune to the SCT canned tune to be able to hold a steady RPM, this video is much better, I don't have an issue that I know of just curious and wanted a second opinion as I am not an expert...

I am slowly rising to 2500rpm in this vid with a high of 3000rpm and holding it there steady...

I guess general health? cat health etc...?

thanks!
 

TexasBlownV8

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I know we used to look at vacuum stability and values in older cars, to asses their "health". The old vac gauge I have was used just for that purpose.

You'd be able to determine if you have developed a vacuum leak, if you know what your car normally was at when working properly.
You won't get an assessment of the health of the cats; that's what the rear O2 sensors are for, making sure the cats are working properly. If you have the rear sensors on, that's all you need.
 

fdjizm

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Thanks bro, I guess I got myself paranoid reading up on cats going bad and people being surprised when their engine blows. doesn't hurt to check!
 

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