Low and Fluctuating Boost Problem
#26
Thanks man, I'm definitely open to try anything right now. Been dealing with it for so long it's disappointing. lol...What confuses me the most is what i see at the boost gauge connected to my actuator. 10 psi actuator and I never see close to 10 on it if I'm not using a boost controller. I even ran a different line, taking my boost controller completely out of the mix and it's the same.
Last edited by NgoRX8; 01-26-2010 at 10:43 PM.
#27
Boosted Kiwi
iTrader: (2)
Initial thoughts are the flow/boost/hp charts line up to what I would expect to see in that the relationship between them makes sense. The way the MAF jumps around at higher rpm could be a clue .........
Need to think about it some more .
How about that BOV test ?
Need to think about it some more .
How about that BOV test ?
Last edited by Brettus; 01-26-2010 at 11:14 PM.
#31
Boosted Kiwi
iTrader: (2)
on second thoughts I do believe your charts are out of whack with eachother .
with over 300 g/s you should be making way more hp than 250
but 6psi and 250hp line up pretty well
So the inference is that there is more air going past the maf than is making it to the engine .
Seeing as you don't have any boost leaks I would definately look at the BOV .............
yes , the BOV could leak even if it pressure tests ok . Not sure if unplugging it will seal it up or not .............. Is there an easy way top block it off at the flange ?
with over 300 g/s you should be making way more hp than 250
but 6psi and 250hp line up pretty well
So the inference is that there is more air going past the maf than is making it to the engine .
Seeing as you don't have any boost leaks I would definately look at the BOV .............
yes , the BOV could leak even if it pressure tests ok . Not sure if unplugging it will seal it up or not .............. Is there an easy way top block it off at the flange ?
Last edited by Brettus; 01-27-2010 at 02:40 AM.
#33
Illudium Q-36 Space Moderator
iTrader: (1)
All those numbers scream boost leak, especially if your AFR's look ok.
Assuming your tune is not so rich as to bog the motor down, or misfire then I'd really me looking for a boost leak or maybe even a WG diaphragm leak... though that usually causes over-boosting not the other way around for an IW.
Assuming your tune is not so rich as to bog the motor down, or misfire then I'd really me looking for a boost leak or maybe even a WG diaphragm leak... though that usually causes over-boosting not the other way around for an IW.
#35
Administrator
iTrader: (7)
Ngo, looks like you're going to be busy testing out a bunch of things but THANKS to all who are helping to try and diagnose this issue.
SoCal needs more boosted 8's!
SoCal needs more boosted 8's!
#38
So I did a few 2nd gear runs. looks like I was wrong...
Going WOT at 4k rpm I would hit between 8-9 psi before it begins to drop
Going WOT at 6k rpm I would hit between 6-7 psi before dropping
This was with the boost controller on.
Looks to be similar in regards to my boost profile from the dyno.
Brettus, did you want me to do a WOT run at 7000 rpm with the wastegate disconnected to see if it goes over 6 psi?
Going WOT at 4k rpm I would hit between 8-9 psi before it begins to drop
Going WOT at 6k rpm I would hit between 6-7 psi before dropping
This was with the boost controller on.
Looks to be similar in regards to my boost profile from the dyno.
Brettus, did you want me to do a WOT run at 7000 rpm with the wastegate disconnected to see if it goes over 6 psi?
#45
Administrator
iTrader: (7)
damn it, I was really hoping it would be the BOV.