Stock Greddy Turbo or Booost Controller Problems?
03-26-2008, 07:38 PM
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Stock Greddy Turbo or Booost Controller Problems?
I have a stock greddy turbo kit with no cat, and with fix #2, and 3" exhaust. the most boost I could get with the boost controller turned off was about 4-5, which I thought was normal.
Then with the boost controller on, and adjusted accordingly (profec b spec II), on hi, with 75%, set boost at 3psi, gain at 5% the most boost I could get was 5-6, which I wasn't sure was normal, but assuming there are a lot of bottlenecks to account for this, I thought it was normal. it has been with these settings for several days now.
Just today I was driving up a long hill and in boost, when I think something popped or snapped. That might not be a good description because i did not feel or hear something, it was just something to describe what happened next. The boost guages suddently shot up past 10 and the beeping alarm went off on the profec. my other boost guage also shot up past ten. i quickly upshifted and eased off on the throttle and both guages (profec and analog guage) quickly shot up past ten again.
Normally I would think this was cool and would think, wow, i can get up to over 10psi with my stock greddy kit, but my car is not running 100% so i don't really push it at all and this is inconsistent with how my car normally runs. I was just in a bit of a hurry to get up this hill.
I'm just wondering if this sounds familiar to anybody or if anyone could guess what happened and tell me where to look first. I didn't install any of this so I have no idea what to check first, i was thinking all the small pressure/vacuum lines etc. and the boost controller line, but am not sure. Does it sound like i popped a line somewhere or maybe some line was folded and all of the sudden 'un-folded' so now it is actually working normally? I turned the boost controller off for the time being and didn't get a chance to see what happens if i go into boost again now, but i will try it tonight. But even if a line was folded and now unfolded and working normally, it wouldn't account for 75% setting meaning that if my max boost with controller turned off was 5, i shouldn't be going past, say, approximately just under9.
I'm just wondering if it sounds like something very obvious happening with my car that I don't know about. Thanks
Then with the boost controller on, and adjusted accordingly (profec b spec II), on hi, with 75%, set boost at 3psi, gain at 5% the most boost I could get was 5-6, which I wasn't sure was normal, but assuming there are a lot of bottlenecks to account for this, I thought it was normal. it has been with these settings for several days now.
Just today I was driving up a long hill and in boost, when I think something popped or snapped. That might not be a good description because i did not feel or hear something, it was just something to describe what happened next. The boost guages suddently shot up past 10 and the beeping alarm went off on the profec. my other boost guage also shot up past ten. i quickly upshifted and eased off on the throttle and both guages (profec and analog guage) quickly shot up past ten again.
Normally I would think this was cool and would think, wow, i can get up to over 10psi with my stock greddy kit, but my car is not running 100% so i don't really push it at all and this is inconsistent with how my car normally runs. I was just in a bit of a hurry to get up this hill.
I'm just wondering if this sounds familiar to anybody or if anyone could guess what happened and tell me where to look first. I didn't install any of this so I have no idea what to check first, i was thinking all the small pressure/vacuum lines etc. and the boost controller line, but am not sure. Does it sound like i popped a line somewhere or maybe some line was folded and all of the sudden 'un-folded' so now it is actually working normally? I turned the boost controller off for the time being and didn't get a chance to see what happens if i go into boost again now, but i will try it tonight. But even if a line was folded and now unfolded and working normally, it wouldn't account for 75% setting meaning that if my max boost with controller turned off was 5, i shouldn't be going past, say, approximately just under9.
I'm just wondering if it sounds like something very obvious happening with my car that I don't know about. Thanks
Last edited by Grouch; 03-26-2008 at 07:41 PM.
03-26-2008, 08:46 PM
#4
it might be something wrong, make sure you check it out....
but it's easy for the greddy turbo to spool to 10+ psi in the low to mid rpm range.
The 75% setting is not good. Turn it down to around 25-35 range. That number determines your psi. So assuming everything is working OK, on my car 40% = 10 psi.
but it's easy for the greddy turbo to spool to 10+ psi in the low to mid rpm range.
The 75% setting is not good. Turn it down to around 25-35 range. That number determines your psi. So assuming everything is working OK, on my car 40% = 10 psi.
03-26-2008, 09:46 PM
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bad wastegate vacuum signal or buggered wastegate most likely.
+1 on DON'T DRIVE IT UNTIL YOU GET THIS FIGURED OUT
...that is, unless you don't mind paying for an engine rebuild.
+1 on DON'T DRIVE IT UNTIL YOU GET THIS FIGURED OUT
...that is, unless you don't mind paying for an engine rebuild.
03-26-2008, 10:53 PM
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vacuum at idle is about -8
i drove it afterwards, just to get home, but very very very carefully at low load, not in boost, and it felt 100% normal. I was thinking something may have been wrong also before this happened if i could only hit 6 or so psi at 75% setting. I already turned the boost controller off and I'm going to get under the car in the daytime when i can see, and trace everything and see if i can move everything properly with my fingers, thanks!
i drove it afterwards, just to get home, but very very very carefully at low load, not in boost, and it felt 100% normal. I was thinking something may have been wrong also before this happened if i could only hit 6 or so psi at 75% setting. I already turned the boost controller off and I'm going to get under the car in the daytime when i can see, and trace everything and see if i can move everything properly with my fingers, thanks!
03-27-2008, 02:25 AM
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I always thought I had a vacuum leak or a minor or small vacuum leak but it might be unrelated to what happened. I thought so because I remember at idle my profec would say -99, which I guess is the limit at -9.9 psi. But now it says about -8 at idle but of course during engine breaking it's -9.9 so I think I got confused and ignored the leak.
I also think I read somewhere here that at idle the profec should read -9.9 meaning vac should be a number below that, but I don't know what vac should be. Wouldn't a vac. leak lower my max boost anyways?
The greddy boost guage at idle reads about 15 inHg, I guess it's negative but the guage doesn't specifically say it. It is below the zero point, and the scale above the zero is in psi, but below is in inHg, and a different scale too. If I extrapolate the bottom to match the top, which I'm not sure I can do, it would read about -7.5 psi, but reading it as is, it looks like 15 inHg, below the zero.
This seems about right since -8 psi is about -16 in Hg.
I did my best to check the lines in the dark with a flashlight (couldn't see everything), but what I could see, and tug on, all clamps are tight, all small lines are also snug and strapped, but it's hard to tell if those crappy hoseclamps are evenly snug around all the couplings. I'll wait till daylight to hand-tighten everything and see more detail. From what I could see, everything is fine.
I took the car very gently around the block, and it feels 100% perfect with boost guage off. I slowly worked my way up over a 30 min period to full boost and it maxed out at the expected <5 psi with boost controller off so it seems perfectly fine now. So I suspect it was just my profec actin up.
I've noticed that the thing was not consistent with the settings, although I haven't properly set it up yet. I guess 75% is too high, although it never caused this problem before.
I thought it worked like this: max boost, with controller off, is, say 5. .75 x 5 is about 3.75 so I was guessing 8.75 would be my boost setting at 75%. With this setting it maxed out at under 6, but I don't know why this time it jumped to over ten. I have to check the lines and actuator in the daylight, I guess.
I also think I read somewhere here that at idle the profec should read -9.9 meaning vac should be a number below that, but I don't know what vac should be. Wouldn't a vac. leak lower my max boost anyways?
The greddy boost guage at idle reads about 15 inHg, I guess it's negative but the guage doesn't specifically say it. It is below the zero point, and the scale above the zero is in psi, but below is in inHg, and a different scale too. If I extrapolate the bottom to match the top, which I'm not sure I can do, it would read about -7.5 psi, but reading it as is, it looks like 15 inHg, below the zero.
This seems about right since -8 psi is about -16 in Hg.
I did my best to check the lines in the dark with a flashlight (couldn't see everything), but what I could see, and tug on, all clamps are tight, all small lines are also snug and strapped, but it's hard to tell if those crappy hoseclamps are evenly snug around all the couplings. I'll wait till daylight to hand-tighten everything and see more detail. From what I could see, everything is fine.
I took the car very gently around the block, and it feels 100% perfect with boost guage off. I slowly worked my way up over a 30 min period to full boost and it maxed out at the expected <5 psi with boost controller off so it seems perfectly fine now. So I suspect it was just my profec actin up.
I've noticed that the thing was not consistent with the settings, although I haven't properly set it up yet. I guess 75% is too high, although it never caused this problem before.
I thought it worked like this: max boost, with controller off, is, say 5. .75 x 5 is about 3.75 so I was guessing 8.75 would be my boost setting at 75%. With this setting it maxed out at under 6, but I don't know why this time it jumped to over ten. I have to check the lines and actuator in the daylight, I guess.
Last edited by Grouch; 03-27-2008 at 02:27 AM.
03-27-2008, 06:42 AM
#17
you should be seeing -17 to -19 psi on your boost gauge at idle. But that can change depending on radiator fan and other stuff.
If your leak is a blown coupler you can be sucking in dirt into your engine. Check the reducing coupler just below the charge tube (next to the fuse box) since that one breaks easily.
If your leak is a blown coupler you can be sucking in dirt into your engine. Check the reducing coupler just below the charge tube (next to the fuse box) since that one breaks easily.
03-27-2008, 08:08 AM
#18
I just bought 9 turbonetics silicone couplers because the ones on my FMIC are starting to crack. The stock couplers are junk and should be replaced ASAP!
Here is a list of the sizes you need.
Hose 3.0″ x1
Hose 2.0″ x2
Hose 2.5″ x3
Reducer 2.0″ -> 2.5″ x1
Reducer 2.5″ -> 3.0″ x1
Reducer 3.0″ -> 3.5″ x1
Here is a list of the sizes you need.
Hose 3.0″ x1
Hose 2.0″ x2
Hose 2.5″ x3
Reducer 2.0″ -> 2.5″ x1
Reducer 2.5″ -> 3.0″ x1
Reducer 3.0″ -> 3.5″ x1
Last edited by turborx8; 03-27-2008 at 08:14 AM.
03-27-2008, 09:48 AM
#19
The Professor
Uh, there is absolutely no such thing as - psi.
inches of mercury is used because it signifies how much of a known substance the vacuum will pull up a straigt column.
inches of mercury is used because it signifies how much of a known substance the vacuum will pull up a straigt column.
03-27-2008, 10:03 AM
#21
The Professor
negative boost, that did make me laugh a bit.Pressure is a gas property, vacuum is a atmospheric differential property. Neither are negative numbers. Though you could convert their effect to a negative number, it would be a conceptual error since the systems are different.
03-27-2008, 10:09 AM
#22
The Professor
For pressure, psi, bar, whatever: you put X gas in a jar. It just sits there by itself, and forevermore, it will press on the walls as hard as uh, lets say 6psi. that is the force the gas is exerting because of its excited molecules.
For vacuum, mmHg, inHg, something is displacing the air in X space. The space is now slightly void of its normal mixture of air. mmHg is used to signify how strongly the air around this space wants to rush in and fill that space. standard conversions like mmHg to bar work because we are talking about the planet's atmosphere, since it is the thing that will be filling the space (as long as we are on this planet at least).
For vacuum, mmHg, inHg, something is displacing the air in X space. The space is now slightly void of its normal mixture of air. mmHg is used to signify how strongly the air around this space wants to rush in and fill that space. standard conversions like mmHg to bar work because we are talking about the planet's atmosphere, since it is the thing that will be filling the space (as long as we are on this planet at least).
03-27-2008, 10:17 AM
#23
The greddy boost gauge registers PSI over 0, and when it's under 0 it registers negative PSI numbers on the dial.
For the sake of this discussion thread, what you're going after is meaningless. I can directly compare with him using negative PSI numbers.
For the sake of this discussion thread, what you're going after is meaningless. I can directly compare with him using negative PSI numbers.
03-27-2008, 10:26 AM
#24
Now turbo!
I just bought 9 turbonetics silicone couplers because the ones on my FMIC are starting to crack. The stock couplers are junk and should be replaced ASAP!
Here is a list of the sizes you need.
Hose 3.0″ x1
Hose 2.0″ x2
Hose 2.5″ x3
Reducer 2.0″ -> 2.5″ x1
Reducer 2.5″ -> 3.0″ x1
Reducer 3.0″ -> 3.5″ x1
Here is a list of the sizes you need.
Hose 3.0″ x1
Hose 2.0″ x2
Hose 2.5″ x3
Reducer 2.0″ -> 2.5″ x1
Reducer 2.5″ -> 3.0″ x1
Reducer 3.0″ -> 3.5″ x1
I bought a new set of couplers and clamps from MazdaManiac, but haven't received them yet.
Mazsport also advertises a replacement set for the GReddy kit, but they don't advertise price or brand.