Tips on finding missing boost
- Thread starter -Nemesis-
- Start date
The 1UZFE EGR Delete Kit is available for sale here.
-Nemesis-
New Member
I might be clutching at straws but I thought of a few more things. The blanked off hose from under the throttle body has an actual bolt in it with a hose clamp, I also used a bolt when testing the PCV hose last night. I guess boost could climb up and out the thread....
When I tried to pressure test the manifold by connecting a blank with valve stem to the the throttle body, all it would do is keep pumping air in and not build pressure, even with the throttle body closed. Is that normal, or should it build pressure does anyone know?
When I tried to pressure test the manifold by connecting a blank with valve stem to the the throttle body, all it would do is keep pumping air in and not build pressure, even with the throttle body closed. Is that normal, or should it build pressure does anyone know?
-Nemesis-
New Member
So I just blanked off the inlet (at TB) and pressurised the intake from the charger to the TB mouth. The pipe won't hold pressure for long!
Problem is, I can't find the leak with soapy water but you can hear it around the MAF area. Using a hose to my ear like a stethoscope it would appear that the air is coming out from the air flow meter, from under the black cover on top that the plug goes into.
Anyone heard of that before? Is there an o-ring or something in there where the sensor passes into the MAF? Can I just pull the black bit off and have a look or is it sensitive gear under there?
Problem is, I can't find the leak with soapy water but you can hear it around the MAF area. Using a hose to my ear like a stethoscope it would appear that the air is coming out from the air flow meter, from under the black cover on top that the plug goes into.
Anyone heard of that before? Is there an o-ring or something in there where the sensor passes into the MAF? Can I just pull the black bit off and have a look or is it sensitive gear under there?
-Nemesis-
New Member
So I just blanked off the inlet (at TB) and pressurised the intake from the charger to the TB mouth. The pipe won't hold pressure for long!
Problem is, I can't find the leak with soapy water but you can hear it around the MAF area. Using a hose to my ear like a stethoscope it would appear that the air is coming out from the air flow meter, from under the black cover on top that the plug goes into.
Anyone heard of that before? Is there an o-ring or something in there where the sensor passes into the MAF? Can I just pull the black bit off and have a look or is it sensitive gear under there?
Problem is, I can't find the leak with soapy water but you can hear it around the MAF area. Using a hose to my ear like a stethoscope it would appear that the air is coming out from the air flow meter, from under the black cover on top that the plug goes into.
Anyone heard of that before? Is there an o-ring or something in there where the sensor passes into the MAF? Can I just pull the black bit off and have a look or is it sensitive gear under there?
-Nemesis-
New Member
Thanks mate, trying to upload a pic.
On closer inspection it looks like the top cover of the black box (it's kind of plastic welded on around the seam on the edges) has split a bit on one corner and that's where the air is coming out. You can actually press the plastic down again and watch the gap dissapear.
Same problem? Maybe a leaking oring has pressurised the internals and caused it to split....
On closer inspection it looks like the top cover of the black box (it's kind of plastic welded on around the seam on the edges) has split a bit on one corner and that's where the air is coming out. You can actually press the plastic down again and watch the gap dissapear.
Same problem? Maybe a leaking oring has pressurised the internals and caused it to split....
-Nemesis-
New Member
Thanks mate, trying to upload a pic.
On closer inspection it looks like the top cover of the black box (it's kind of plastic welded on around the seam on the edges) has split a bit on one corner and that's where the air is coming out. You can actually press the plastic down again and watch the gap dissapear.
Same problem? Maybe a leaking oring has pressurised the internals and caused it to split....
On closer inspection it looks like the top cover of the black box (it's kind of plastic welded on around the seam on the edges) has split a bit on one corner and that's where the air is coming out. You can actually press the plastic down again and watch the gap dissapear.
Same problem? Maybe a leaking oring has pressurised the internals and caused it to split....
spf_lexus
Active Member
what does the rubber "O" ring look like? Once the sensor is removed it has a small grommet sealing it into the housing, could it just be worn out?
Hey worst case.... JB that SOB and never remove again lol. If it's working fine then clean it up well and permanently seal it (thats if the o ring is good). Just an idea.
Hey Nem, I thought of this right after I posted. What about welding in bicycle inner-tube type valve and pressurize the whole system w/ a bike pump. I don't know if you tried this with the soap but it's similar. Completely seal off the intake pipe before it enters TB and test for leakdown. Sorta like a makeshift compression tester. I have heard of a few people doing this to pre-test newly installed turbocharged engines. I don't know where to look but i now a metal flanged valve can be bought for this specific setup.
Hey worst case.... JB that SOB and never remove again lol. If it's working fine then clean it up well and permanently seal it (thats if the o ring is good). Just an idea.
Hey Nem, I thought of this right after I posted. What about welding in bicycle inner-tube type valve and pressurize the whole system w/ a bike pump. I don't know if you tried this with the soap but it's similar. Completely seal off the intake pipe before it enters TB and test for leakdown. Sorta like a makeshift compression tester. I have heard of a few people doing this to pre-test newly installed turbocharged engines. I don't know where to look but i now a metal flanged valve can be bought for this specific setup.
spf_lexus
Active Member
what does the rubber "O" ring look like? Once the sensor is removed it has a small grommet sealing it into the housing, could it just be worn out?
Hey worst case.... JB that SOB and never remove again lol. If it's working fine then clean it up well and permanently seal it (thats if the o ring is good). Just an idea.
Hey Nem, I thought of this right after I posted. What about welding in bicycle inner-tube type valve and pressurize the whole system w/ a bike pump. I don't know if you tried this with the soap but it's similar. Completely seal off the intake pipe before it enters TB and test for leakdown. Sorta like a makeshift compression tester. I have heard of a few people doing this to pre-test newly installed turbocharged engines. I don't know where to look but i now a metal flanged valve can be bought for this specific setup.
Hey worst case.... JB that SOB and never remove again lol. If it's working fine then clean it up well and permanently seal it (thats if the o ring is good). Just an idea.
Hey Nem, I thought of this right after I posted. What about welding in bicycle inner-tube type valve and pressurize the whole system w/ a bike pump. I don't know if you tried this with the soap but it's similar. Completely seal off the intake pipe before it enters TB and test for leakdown. Sorta like a makeshift compression tester. I have heard of a few people doing this to pre-test newly installed turbocharged engines. I don't know where to look but i now a metal flanged valve can be bought for this specific setup.
-Nemesis-
New Member
So I drove home last night after welding the AFM and nothing changed, sucks. But.....
Today I tried again, pressure tested again and found it was still leaking, so I did more plastic welding on the car. Then I took the air filter off and went for a drive around the streets with a bare blower.
SWEET F'N JEEBUS! That's how a boosted 8 should go! Damn thing was tail dragging almost lol
I didn't go much past 4000rpm (suburbs) in first and second and was hitting 6psi at those revs! Felt like more power ATW than 6000rpm and 5.5psi like when dyno'd!
Looks like my plan could work after all. I'm guessing it's capable of near 10psi if I keep revving, but if I can cap it at say 7, I should have almost max boost by mid 4krpm
Today I tried again, pressure tested again and found it was still leaking, so I did more plastic welding on the car. Then I took the air filter off and went for a drive around the streets with a bare blower.
SWEET F'N JEEBUS! That's how a boosted 8 should go! Damn thing was tail dragging almost lol
I didn't go much past 4000rpm (suburbs) in first and second and was hitting 6psi at those revs! Felt like more power ATW than 6000rpm and 5.5psi like when dyno'd!
Looks like my plan could work after all. I'm guessing it's capable of near 10psi if I keep revving, but if I can cap it at say 7, I should have almost max boost by mid 4krpm
spf_lexus
Active Member
Nice job nem!!!! That air leak of yours was causing some real headaches. lol fun power right? It feels like such a dog when you have to swap the blower out and drive it N/A.... you won't want to go back. So are you planning the boost controller idea? that would be sweet for 10psi, just cut out the top 3 or so and more low end.10psi would be 350-375rwhp. Sweet dude!! lets get some pics!!!
stevechumo
Active Member
Every single psi is a lot of difference. The 1UZ puts out an average of 20 bhp per psi. If you run a little more boost than 8 psi, make sure you have proper fuel feed. And timing retard is required if you run over 12 psi.
spf_lexus
Active Member
The idea is to have our cake and eat it too. mount a pulley thats too small for the desired boost, and run wastegate as BPV and limit the top boost from 10 to 7 meanwhile keeping the quicker spool-up from the smaller dia. I wanted the electric option for it's in cabin blingness but I will probably just run a mechanical and mark + fix at 7psi. I suppose an even smaller like 13psi and even higher could be used to cut out more lag but a double/triple check of boost is a good idea. After all these units are rated to 30psi so there isn't much sacrifice in hp terms. it's sorta scary knowing if something fails that your engine might boost 13psi instead of 7psi... but if it was hooked up right with possibly some sort of failsafe device then it could be quite the sleeper mod. it's like a roots/turbo hybrid hehe
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