Second turbo, little boost?
#1
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Second turbo, little boost?
Ok, so I thought that my boost controller was acting up because I wasn't getting any kind of "push" when my 2nd turbos kicked in. I drove to Rotary Extreme and talked to Chuck and after redlining in 2nd gear down a road, he saw that when the 2nd turbo kicks in, my boost gauge shows around .4bar. So he said that I should check one of the clamps and replace it anyways because they split. The second thing was to check the pipe going into the IC to make sure there was no kind of cracks because he said they have a tendency to crack. Then he told me that after checking those, that if I don't see anything wrong that it could be my turbo.
Now here is the story. A couple weeks ago, I was getting on the freeway and I was going on my 2nd turbo and I heard a pop and then whooshing sound and my boost died down. Then a week later, again I was driving on the freeway just crusing and I heard something loud hit my car. Now it sounded as if it was in my engine on the passenger side and then it hit something on the side or under the car. I don't know if something from the engine bay came out and dropped down or if I just ran over something.
From everyones experience what do you guys think it is? I'm hoping it's just a clamp, but we'll see. So in short, I believe my first turbo is fine, it goes to around .5-.6bar (because I have my boost controller cut boost down when it reaches 9.5psi) and then when second turbo kicks in, it drops and barelly stays above vaccum.
Now here is the story. A couple weeks ago, I was getting on the freeway and I was going on my 2nd turbo and I heard a pop and then whooshing sound and my boost died down. Then a week later, again I was driving on the freeway just crusing and I heard something loud hit my car. Now it sounded as if it was in my engine on the passenger side and then it hit something on the side or under the car. I don't know if something from the engine bay came out and dropped down or if I just ran over something.
From everyones experience what do you guys think it is? I'm hoping it's just a clamp, but we'll see. So in short, I believe my first turbo is fine, it goes to around .5-.6bar (because I have my boost controller cut boost down when it reaches 9.5psi) and then when second turbo kicks in, it drops and barelly stays above vaccum.
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Where is the coupler located? I have never worked on this or any car before so I am new to everything. It might sound as though there is a boost leak when the secondary turbo kicks in, I just hear like a "whishing" sound and no push at all as my rpm's climb.
#5
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its on the passenger side. standing in front of the car follow the crossover piping back and to your left. it will then curve downward, and there is your coupler between the crossover and y-pipe.
i have this same problem, my crossoverpipe pops loose... get a efini pipe will fix this problem. gl on any others there may be..
i have this same problem, my crossoverpipe pops loose... get a efini pipe will fix this problem. gl on any others there may be..
#6
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I think that's the coupler Chuck was talking about. He said just to replace that (said it should be $10-$15 the most) and see if it fixes it. Are we talking about the same thing? It's like a rubber seal right?
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Yeah when I brought it to Rotary Extreme Chuck and I took a look, he said that the first thing is to replace one of the clamps because it has a tendency to split, then he also said to check the piping going into the IC, we looked at it a little and saw that it had a forming of a crack.
I think I'm going to bring it to Paul and Rotorsport and have him check it out and diagnose everything.
I think I'm going to bring it to Paul and Rotorsport and have him check it out and diagnose everything.
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Bump
When I get full boost in primary but very little (2-3psi) in secondary turbo, does that automatically mean my secondary turbo is busted? Because if there was a leak, wouldn't that mean that I wouldn't get full boost in primary turbo?
When I get full boost in primary but very little (2-3psi) in secondary turbo, does that automatically mean my secondary turbo is busted? Because if there was a leak, wouldn't that mean that I wouldn't get full boost in primary turbo?
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Originally Posted by HardHitter
Bump
When I get full boost in primary but very little (2-3psi) in secondary turbo, does that automatically mean my secondary turbo is busted? Because if there was a leak, wouldn't that mean that I wouldn't get full boost in primary turbo?
When I get full boost in primary but very little (2-3psi) in secondary turbo, does that automatically mean my secondary turbo is busted? Because if there was a leak, wouldn't that mean that I wouldn't get full boost in primary turbo?
The next simple/easy/important thing to do is test or replace the check valves. A bad check valve leading to the pressure tank will often make the secondary laggy or low.
But honestly, since you're taking it to shops to get the diagnostics and work done, it's a waste of time to talk about it here. I like to try and help people with their turbo problems, but it's a complicated enough process that it works only if the other person goes and does some DIY work under the hood, then reports the results. Then I suggest the next test or thing, and it repeats until the problem is solved.
Dave
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Ugh, so got a call from Paul from RotorSport and he is going to keep the car over night, it isn't something that was small like a clamp or hose. I really really hope it isn't a blown turbo Anyone else think they know what could be the problem?
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To
also to add to this post, may i have some help with my turbo its almost the same but its oppisite, my primary is boosting like4-5 bars it says on the boost gauge then 10-12 when secondary kicks in, is this normal?
#19
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Originally Posted by HardHitter
Alright, so average cost to repair one of those would be what?
A very knowledgeable mechanic might find the problem in an hour or two.
Labor is the beast - just to replace a solenoid on the rack, you need to remove the TB, UIM, and coils. Changing all the hoses adds a few hours.
So the bill could vary widely, which is why i DIY it. It takes some patience and time, but you only pay for parts, and can replace other important things while 'in there'. Often the FPD and injectors get changed when doing these jobs under the UIM.
Dave
#20
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Originally Posted by JDawG707
also to add to this post, may i have some help with my turbo its almost the same but its oppisite, my primary is boosting like4-5 bars it says on the boost gauge then 10-12 when secondary kicks in, is this normal?
https://www.rx7club.com/forum/showthread.php?t=68640
Your gauge is probably reading in psi, not bar. (1 bar = 14.5 psi) Do the on-road boost test in 3rd gear, full throttle, starting at 35mph. You should see 10psi between 3000-4500rpm, then 8psi for a moment as it passes 4500, and 10psi above that. It may fall off a little toward 8psi above 6500rpm. 12psi indicates overboost.
Dave
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Originally Posted by dgeesaman
Check the items under "T" in the FAQ thread:
https://www.rx7club.com/forum/showthread.php?t=68640
Your gauge is probably reading in psi, not bar. (1 bar = 14.5 psi) Do the on-road boost test in 3rd gear, full throttle, starting at 35mph. You should see 10psi between 3000-4500rpm, then 8psi for a moment as it passes 4500, and 10psi above that. It may fall off a little toward 8psi above 6500rpm. 12psi indicates overboost.
Dave
https://www.rx7club.com/forum/showthread.php?t=68640
Your gauge is probably reading in psi, not bar. (1 bar = 14.5 psi) Do the on-road boost test in 3rd gear, full throttle, starting at 35mph. You should see 10psi between 3000-4500rpm, then 8psi for a moment as it passes 4500, and 10psi above that. It may fall off a little toward 8psi above 6500rpm. 12psi indicates overboost.
Dave
ive done it, all it reads between 3500-4500 is 6 then 4500-7000 it reads 10
#23
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That gauge is in PSI on the pressure side, and inHg on the vacuum side.
As for your boost issue, it would seem that one of the valves that should be shut during primary turbo operation (turbo control or charge control) is leaking some of the primary boost into the secondary. The KOKO test should be ideal for deciding if one of these is the problem: you'll find it described at www.fd3s.net/boost_test.html
Dave
As for your boost issue, it would seem that one of the valves that should be shut during primary turbo operation (turbo control or charge control) is leaking some of the primary boost into the secondary. The KOKO test should be ideal for deciding if one of these is the problem: you'll find it described at www.fd3s.net/boost_test.html
Dave