nevermind. i see your using rt tunerpro... if your car is running that rich. i would focus solely on your psi drop. so your able to readjust your fuel trims aith a solid number and not trying to adjust with a fluctuating psi drop.
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Don't worry about your low post count. Your theory is about what 50% of folks say anyways. I think what the last poster was trying to get at was whether or not my car was running pig rich due to a boost leak which IMHO it isn't. It's running leaner than the Fuel Maps. Not sure if you are familiar with Ostrich and RT Tuner Pro, but my fuel system is pretty well managed.
Lol, posted over each other. Yeah it's not really running that rich.
The author of the post that I mentioned before....
click
seems to have gotten rid of that problem by paying attention to a series of boost leaks that he found. His setup is different but it is crazy that his problem is/was the same as mine verbatim!
The author of the post that I mentioned before....
click
seems to have gotten rid of that problem by paying attention to a series of boost leaks that he found. His setup is different but it is crazy that his problem is/was the same as mine verbatim!
donniekak
Well-known member
How do you have the wastegate hooked up? To clear out all other possibilities run a pressure only line to the top port of the wastegate and disconnect the other port. Be careful to not over boost to much, as you will need to get out of it quickly. If you now hold boost with this setup, you need a better wastegate spring.
Thanks for joining lol!
Alright, since you mention spring I am sure that you read that it is an external wastegate. I know that the MBC Blow off Valve Tee situation is not right and I will get to that.
Let me explain to the best of my novice ability.
I am running a line from behind the throttle body to the BOV. The line is tee'd and runs to a MBC. from the MBC there is only one line that goes to the External WGA. Is there supposed to be 2 lines going to it or something? I can't recall exactly what it looks like even though I have had it apart a few times (not pleasant have to remove and drain radiator each time).
Alright, since you mention spring I am sure that you read that it is an external wastegate. I know that the MBC Blow off Valve Tee situation is not right and I will get to that.
Let me explain to the best of my novice ability.
I am running a line from behind the throttle body to the BOV. The line is tee'd and runs to a MBC. from the MBC there is only one line that goes to the External WGA. Is there supposed to be 2 lines going to it or something? I can't recall exactly what it looks like even though I have had it apart a few times (not pleasant have to remove and drain radiator each time).
FYI...it is only running to the side port right now...again the top port well there is none...just a hole.
I found out that this is actually correct. The top port is supposed to vent to atmosphere. I guess I need to get a port for the top. I am reading that if I get a port that is too long, that I can rip the diaghpram.
you can jsut leave it open. the double port is used in some higher end electronic boost controllers.
thecman02
Well-known member
Double check your vacuum line feeding your boost gauge for leaks too. It could actually be a higher boost level then your gauge is showing.
Just looking at your setup, I just don't believe the intercooler is the cause of the problem. These problems usually are due to wastegate not staying closed, intake collapsing, bov leaking, or turbo dieing, if taking into consideration no other boost leaks or exhaust leaks which you tested and said are none.
I wanted to hear about your wide band for a multitude of reasons. It says your tune is okay. It double checks pressure leaks. Lastly it makes me worried about your turbo. I've seen maxed out b16g and evo316g's hold over 20 pounds in setups that are way more aggressive then yours to at least 7k. They have intercoolers that would dwarf the one on yours, and agressive cams/smim.
Just looking at your setup, I just don't believe the intercooler is the cause of the problem. These problems usually are due to wastegate not staying closed, intake collapsing, bov leaking, or turbo dieing, if taking into consideration no other boost leaks or exhaust leaks which you tested and said are none.
I wanted to hear about your wide band for a multitude of reasons. It says your tune is okay. It double checks pressure leaks. Lastly it makes me worried about your turbo. I've seen maxed out b16g and evo316g's hold over 20 pounds in setups that are way more aggressive then yours to at least 7k. They have intercoolers that would dwarf the one on yours, and agressive cams/smim.
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I was thinking of double checking the boost gauge line for leaks...I wasn't the one to set it up so I don't know much about how it is run.
I just checked to see which intercooler I have on the car and it is the smallest 3 inch one so I think the intercooler theory is now out the window!
I just checked to see which intercooler I have on the car and it is the smallest 3 inch one so I think the intercooler theory is now out the window!
Update...still have the same problem.
No leak at boost gauge. I went through the expense and huge hassle of swapping the external wastegate springs with 22 psi springs. Have to remove and drain the radiator every time! I bench tested the External Wastegate with a compressor and it won't open until about 24 psi.
I took it for a drive and bypassed the MBC. I connected the boost line directly to the wastegate. I could only get 18 psi of boost.
I put the MBC back and could get 22 psi falling to 18 psi at 4500 rpm. I even blocked the BOV as a test.
Seems like a bad turbo to me. No shaft play in and out whatsoever though. A slight movement side to side.
Any other ideas?
No leak at boost gauge. I went through the expense and huge hassle of swapping the external wastegate springs with 22 psi springs. Have to remove and drain the radiator every time! I bench tested the External Wastegate with a compressor and it won't open until about 24 psi.
I took it for a drive and bypassed the MBC. I connected the boost line directly to the wastegate. I could only get 18 psi of boost.
I put the MBC back and could get 22 psi falling to 18 psi at 4500 rpm. I even blocked the BOV as a test.
Seems like a bad turbo to me. No shaft play in and out whatsoever though. A slight movement side to side.
Any other ideas?
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