Boosting problems.

[XxSiRhCy6PxX]

Alright so my problem my boost wont hold steady. I would try to set my joe p mbc to 15 psi but it fluctuates back and forth from 13-15 psi really fast. Sounds like a police when it does it. I tried to single out the mbc but just connecting a hose replacing my mbc and it stays 10 rock solid. so maybe i thought it was my mbc, but today i tried my friends mbc and its still the same. I did a boost leak test and i only have a little leak from my BISS screw. Could it be my wastegate actuator because before i installed it my friend was messin around with the adjustments? how do i know if its adjusted right? what else could be the culprit?

 

[XxSiRhCy6PxX]

....

 

[kenamond]

Make sure your MBC is properly connected...and don't bump your threads

Try setting your MBC to 11, 12, 13, then 14 and see what happens with each setting. Does the problem show up at a certain level of boost?

 

[WFO-TSi]

Does your 1G BOV leak? Are your BOV and MBC T'ed together from the same boost source?

 

[oldman]

Does your 1G BOV leak? Are your BOV and MBC T'ed together from the same boost source?

Exactly what I was going to ask.

XxSiRhCy6PxX, we don't allow thread bumping so please don't do it again.

 

[XxSiRhCy6PxX]

Yes my bov and mbc are teed together. This all started when i installed my 16g. stock wastegate boost it holds rock solid. anything pass that it starts to fluctuate

 

[oldman]

Yes my bov and mbc are teed together. This all started when i installed my 16g. stock wastegate boost it holds rock solid. anything pass that it starts to fluctuate

Teeing the bov line for the mbc will result in bov opening under boost. First thing you should do is to restore the BOV line to its original state and source your pressure signal from the compressor housing/j-pipe/licp instead.

 

[XxSiRhCy6PxX]

i cant find any boost source anywhere but only from where the bov is. no nipple on my compressor housing nor my j pipe. my licp is rubber so how do i get vacuum from there unless im missing here?

 

[oldman]

i cant find any boost source anywhere but only from where the bov is. no nipple on my compressor housing nor my j pipe. my licp is rubber so how do i get vacuum from there unless im missing here?

In your case you would tap or weld a fitting to the j-pipe.