Strange vaccum problems occasionally

[cmills5081]

Okkk everyone, been having an interesting thing happen lately. When I go to start my car, I usually always wait for check engine light to go off and dinging to stop. But regardless whether I do this or not sometimes when the car starts it will only go to 12 vacuum or so. And then it will like fly down to 18-19 and then it's fine!! But sometimes it will stay on 12 until I drive a block or two down the road and usually it's fine then.

I have tried 2 diff gauges, both doing the same thing. Something I need to worry about?? Or just something dumb and goofy?? And help would be great. Ask any questions you may need to help answer this

Car is basically stock 97 gst with non recirculated BOV

 

[killahb33]

Have you done a boost leak test?

 

[razrman8]

If you car is trying to warm up, your vaccum number will be of a lesser value. For your car is increasing RPM to bring itself to operating temperature. Are your RPM's slightly higher too? That would be an exact representation on what I am talking about. Think of it this way, when you are at idle and you give the car throttle, the boost gauge jumps to 0 right? Because you are increasing RPM, eliminating vaccum, but not creating boost.

If you take it down the road while it is still cold, that is probably why you are getting the reading the 12 vaccum. My car reads low vaccum numbers in the morning when I start it to let it warm up. I come out after its fully warmed up and it is fine. I do not see a problem with it, since it returns to normal.

Recirculate that blow off valve of yours also.

 

[cmills5081]

Have not done boost leak test yet, maybe Friday or this weekend

And it is not only when the car is trying to warm up it can fully warm up and if I shut the car off and turn it right back on it will do it.

Thanks for the ideas so far thoggh