Driving it off the cliff

[Stl-986]

At 1:24 is when it goes back to idle and you can see it dropping.
at 1:40 the cooling fans start to kick in and it drops even more but hard to tell.

I'll do another video in a bit. want to get things setup with the gauge by the cluster. Want to see if you can spot another issue that happens had really has me stumped (but I think it is all related)

[blue62]

Originally Posted by Stl-986

At 1:24 is when it goes back to idle and you can see it dropping.
at 1:40 the cooling fans start to kick in and it drops even more but hard to tell.

I'll do another video in a bit. want to get things setup with the gauge by the cluster. Want to see if you can spot another issue that happens had really has me stumped (but I think it is all related)

Yes watching RPM and the needle is very important.
Hard to relate everything about using that simple little vacuum gauge via the internet

[blue62]

Originally Posted by Stl-986

At 1:24 is when it goes back to idle and you can see it dropping.
at 1:40 the cooling fans start to kick in and it drops even more but hard to tell.

I'll do another video in a bit. want to get things setup with the gauge by the cluster. Want to see if you can spot another issue that happens had really has me stumped (but I think it is all related)

I turned the sound on so I could hear the engine. That little drop in vacuum when the fans kick in is due to a little drop in RPM.
That slow drop at idle looks like you could have some restriction in your exhaust.
Cats may be partially plugged which could lead to random misfires.

When you do your next vacuum test bring the RPM to 2000 and hold it as steady as you can for 2-3 minutes watch the needle. if it drops slowly you have some restriction in the exhaust.