Turbo problems - check valves
#1
Rotary Freak
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Turbo problems - check valves
Recently my turbos have been acting up. I've been reading threads from searches forever now and I think I have some good info.
Anyways, this is what is happening. The car isn't getting full boost at all. When I floor it, it hits around 8-10psi, and then it drops down to 7psi and holds until around 5500rpm and then it pulls stronger than what it was but only goes up to around 8psi.
Then sometimes, the boost doesn't even boost to 7psi. It holds around 1-2psi all the way to redline and even when I shift it holds at 1-2psi. Then after letting off the gas, I hear a moo sort of sound.
After doing searches this is what I've came up with. I've checked my couplings from my IC and y-pipe those are the biggest problems. Those checked out fine. Checked the CRV hose and the BOV hose, those checked out fine. I switched the Prec-ontroller and the other plugs just incase they got switched, still no fix. Here is what I'm thinking, can a faulty check valve keep boost from reaching full boost? As I am boosting it sounds as though there is air or a slight screaming noise but I can't tell where it is coming from. All the valves are pointing towards the UIM. (except the one from pressure chamber)
Regarding the 1-2psi boost hold, I've read many threads of this happening and they say it's the pressure chamber? They said if this happens, let the RPM's go below 3000rpm and then slam it and see if you get full boost again. So when I was testing it, it started happening shifted into 4th and it held 1-2psi again. Engaged the clutch, watched the rpms drop to around 3000rpm and then hit the throttle and full boost again (well 7psi due to above) How do I go about fixing this? This is a check valve that goes to the pressure chamber right?
So after all my research and some testing/checking, can the check valves be the cause of me not boosting completely? I really don't think my turbos are going out, but that could be a possibility, but I'd like to look at my other options.
Anyways, this is what is happening. The car isn't getting full boost at all. When I floor it, it hits around 8-10psi, and then it drops down to 7psi and holds until around 5500rpm and then it pulls stronger than what it was but only goes up to around 8psi.
Then sometimes, the boost doesn't even boost to 7psi. It holds around 1-2psi all the way to redline and even when I shift it holds at 1-2psi. Then after letting off the gas, I hear a moo sort of sound.
After doing searches this is what I've came up with. I've checked my couplings from my IC and y-pipe those are the biggest problems. Those checked out fine. Checked the CRV hose and the BOV hose, those checked out fine. I switched the Prec-ontroller and the other plugs just incase they got switched, still no fix. Here is what I'm thinking, can a faulty check valve keep boost from reaching full boost? As I am boosting it sounds as though there is air or a slight screaming noise but I can't tell where it is coming from. All the valves are pointing towards the UIM. (except the one from pressure chamber)
Regarding the 1-2psi boost hold, I've read many threads of this happening and they say it's the pressure chamber? They said if this happens, let the RPM's go below 3000rpm and then slam it and see if you get full boost again. So when I was testing it, it started happening shifted into 4th and it held 1-2psi again. Engaged the clutch, watched the rpms drop to around 3000rpm and then hit the throttle and full boost again (well 7psi due to above) How do I go about fixing this? This is a check valve that goes to the pressure chamber right?
So after all my research and some testing/checking, can the check valves be the cause of me not boosting completely? I really don't think my turbos are going out, but that could be a possibility, but I'd like to look at my other options.
#3
Mr. Links
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I think you probably have more than one problem.
IMO, I would start from basically 0. Start by checking everything:
1. Recheck your vacuum routing
2. Test the solenoids which only deal with the sequential system (i.e. ignore the emissions solenoids)
3. Test your check valves
4. Check the actuator/valve operations
IMO, I would start from basically 0. Start by checking everything:
1. Recheck your vacuum routing
2. Test the solenoids which only deal with the sequential system (i.e. ignore the emissions solenoids)
3. Test your check valves
4. Check the actuator/valve operations
#4
Rotary Freak
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I just replaced my solenoids, so I'm wondering if the check valves could be a problem that keeps the turbos from boosting all the way or anything?
The car boosts 7psi but it seems like it is NA until 5500rpm where it goes up 1 or 2psi and it kicks in.
The car boosts 7psi but it seems like it is NA until 5500rpm where it goes up 1 or 2psi and it kicks in.
#6
Rotary Freak
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Originally Posted by HardHitter
I just replaced my solenoids, so I'm wondering if the check valves could be a problem that keeps the turbos from boosting all the way or anything?
The car boosts 7psi but it seems like it is NA until 5500rpm where it goes up 1 or 2psi and it kicks in.
The car boosts 7psi but it seems like it is NA until 5500rpm where it goes up 1 or 2psi and it kicks in.
Check out the test here:
Check these threads for Dave Disney's pressure testing of solenoids:
http://rx7.voodoobox.net/howto/sole...noid_check.html
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/weird-boost-issue-341534/
:-) neil
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#10
Potato Love
I replaced some stuff and the new line I installed at one point kinked, giving me erratic boost problems. It was barely noticeable. I replaced the hose again with one that had an extra thick wall. It's a long shot but possible.
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So did you fix it and if so how? I have the exact same problem right now i have not had time to look much into it but by ur description even to the moo sound it is the same. I did try when it is only boosting 1-2 psi letting off the gas and going back oner i got maybe 6 but not the normal 8-10.
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