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idle vacuum pressure to high


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I was told my intake manifold vacuum pressure was high. Which may be why my fuel trims are positive.

 

I find it hard to believe I tightened and made everything so secure that vacuum increased better than stock lol.

 

Is there anything that regulates manifold pressure like a valve?

 

They billed me 200 bucks and they didn't even find the problem.... gotta love the stearlership.

 

I'm at 21-22 in/hg or 71-75 kpa.

 

I'm at stage 3 with bnr 18g, 1000cc top feed injectors. ebcs, tmic, everything else is pretty much stock.

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Tune stage, type of turbo and injectors have no bearing on idle vacuum. Compression ratio might a little if you had a built motor with really high compression, but I doubt it.

 

Your in/hg are completely normal. I idle at between 20 and 22 depending on weather. Sounds like they took you for a fool to the tune of 200 bucks.

 

Now if you had an intake leak pre-turbo, that could affect your A trim, but wouldn't show up on a boost gauge.

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Isn't a leak at the compressor housing...loosing boost ? I would have thought that would be pretty tight there. ?

 

Have you asked a Tuner ?

 

I know a good one...

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

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The only thing leaking is the back of intake housing on turbo at the bolts, but when I called bnr they said its normal...

 

If you are talking about the intake side of the turbo compressor, that's a pre-turbo leak and probably the cause of your trims being wonky. The air being sucked in there is not being measured by the MAF sensor because it is entering the system after the MAF.

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I don['t believe you should have a leak at the back of the compressor housing where it mates to the center section. I'm no turbo manufacture...but that doesn't sound like something that's good.

 

I just to be a jet engine mechanic in the USAF, I don't remember any of the compressor cases leaking... At work, out in the shop they build lots of centrifical flow compressors for the aircraft industry. I doubt any of those leak on the back side of the coompressor.

 

Sounds like may be you want to ask a Tuner or one of the Mike's.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Its coming out the seam made by the 6 small bolts ... Wait so what about what the people who made the turbo are saying? Its not like this is the first turbo BNR has made. Why would they tell me its fine?
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That's why one of the Mikes would be my next step. Ask m sprank if he can check a car and see if there air pressure coming out of the turbo where it mates to the center section.

 

 

That's a machined surface, fit. Is there really a seal area there ?

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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You most likely had a small leak somewhere when the car was getting tuned. And it got fixed after the tune was completed. My guess is your tune needs a slight adjustment. Your idle vacuum levels sound normal.
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Hello there,

 

We are actually mid tune and have been for quite some time due to mechanical issues ranging from bad turbos, failed fpr, bad pcv, wideband issues and laptop communication issues. I agree your vac level is not anything I would be majorly concerned about at that value.

 

Hoping we can finally nip it in the bud and continue dialing in the injectors/tune but we are getting very different data each time with minimal changes to the tuning side thus another potential mechanical issue.

 

I smoke test cars all the time and do not normally see any leaks at the turbocharger. I sent an email last night about the updated info. Depending on what we see there will determine if it's anything we can adjust properly via tuning or if we will have to re evaluate our options.

 

Dave

[sIGPIC][/sIGPIC]

Providing unmatched customer service and a Premium level of Dyno/E-tuning to the Community

 

cryotuneperformance@yahoo.com

facebook.com/cryotuneperformance.

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Just checked my old vf40, there is a red seal on the housing, IMO air should not be leaking at the housing to center section joint.

 

I can get a picture if you want.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Trims are actually looking a lot better with the new valve purge, the one that feeds into the fuel rail and T under IC. If its installed incorrectly it will pull air from fueling system I'm guessing. Not sure but thats the only explanation for my trims dropping. Looks like a 30 dollar valve that was in backwards gave me all this headache.......
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So how did it get installed backwards ? Did you just do some maintenance ?

 

Do you know where I'm going here ? ;)

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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