Vacuum pressure what is a good range.

[Luckydawg75]

Okay took the car in for a replacement on the water pump, get it back and only pulling 6-8 pounds of boost from 4th to 6th gear. Tightened up some clamps that the techs I guess forgot or didn’t think needed to be tighter then what they were, seemed to correct some of the issue. Now I am getting about 9-10 between 4th and 6th and 5-6 from 1st -3rd gears. So I guess the real question is, does the current boost seem correct and can you tell anything with the current vacuum readings.

 

[Das Gespenst]

Hang on, are you asking what correct boost or vacuum levels are?

Are you tuned?

 

[Luckydawg75]

nope running stock tune.

 

[Luckydawg75]

nope running stock tune. with DSG

 

[jesus.u.villagomez]

I usually get 9-10 psi during second gear around 3500rpms. I'm also stock tune.


-Jesus

 

[Das Gespenst]

That is a good range for the stock tune, and that is boost you're talking about not vacuum. With best possible conditions I would hit 13psi at peak.

 

[Luckydawg75]

The only reason is a I noticed my vacuum pressure go from 9HG to 20HG at idle. When moving it rests about 9-12HG and of course gassing it moves to boost, So I guess or is it possible to determine a boost leak with the vacuum pressure.

 

[Mataleao9380]

My guage stays on 20hg on idle and only fluctuates to 19hg every so often. You most likely have a leak. Start looking at the boost gauge lines and tap/connectors and go from there.

 

[Luckydawg75]

I do have a Boost tap and it is very snug in the PVC on the intake side. I have FMIC that works with the stock intercooler. I have a feeling it is that so I might have to modify this to just use the front mount inter cooler then test, then more then likely go back to stock.

 

[Das Gespenst]

Yeah that's a huge swing at idle. Very good likely hood you have a leak, I'm assuming your RPM'S also fluctuate and go to a high idle?

 

[Luckydawg75]

Not really Das, at start it is hitting Idle about 1K, then after a few it drops to about 800. So nothing really concerning their. I did move to just the Front mount intercooler and noticed the Vac get to 21HG but the boost dropped to around 7-8 Max. Have a feeling I just have to drop the FMIC and go back to stock and leave it at that. I still have all the pipes and fittings. I have only been able to get 10PSI steady with the front mount for about a week after the intake was replaced. Since the water pump was replaced it only goes to 8, so I am just ditching the all Idea and going back to stock.