I've lost some boost?
Thread Starter
TECH Resident
Joined: Jan 2004
Posts: 832
Likes: 0
From: Castro Valley, CA
I've lost some boost? Search is 
on me, so I figured I'd just post up.
Went out on Friday the 13th, I know, what was I thinking, to do some highway pulls with some friends. Didn't really destroy them like I thought I should've... concentrating on the road and didn't realize until later that the peak boost recorded on the Eboost was only 4.6 psi, instead of my usual 11.5 or so. So I lost 7 lbs of boost out there somewhere. A couple of WOT blasts yesterday confirm that I'm still not seeing any more than 4.6 psi.
So I thought I'd ask to see what items on the "EASY" list I should check prior to dropping it off at the shop. Obviously checking the pressure side plumbing and clamps, and making sure that the Eboost solenoid and associated boost controller reference lines. What else?
The wastegate runs on a 7 psi spring, so I would've expected that a disconnect on the boost controller stuff would've dropped me down to 7 psi. But not all the way to 4.5, right?
Any simple tricks of the trade when searching for a leak?
Thanks in advance for any ideas,
Rich
on me, so I figured I'd just post up.Went out on Friday the 13th, I know, what was I thinking, to do some highway pulls with some friends. Didn't really destroy them like I thought I should've... concentrating on the road and didn't realize until later that the peak boost recorded on the Eboost was only 4.6 psi, instead of my usual 11.5 or so. So I lost 7 lbs of boost out there somewhere. A couple of WOT blasts yesterday confirm that I'm still not seeing any more than 4.6 psi.
So I thought I'd ask to see what items on the "EASY" list I should check prior to dropping it off at the shop. Obviously checking the pressure side plumbing and clamps, and making sure that the Eboost solenoid and associated boost controller reference lines. What else?
The wastegate runs on a 7 psi spring, so I would've expected that a disconnect on the boost controller stuff would've dropped me down to 7 psi. But not all the way to 4.5, right?
Any simple tricks of the trade when searching for a leak?
Thanks in advance for any ideas,
Rich
correct, if your controller was not working you would still see the wg spring pressure. The fact that you aren't tells me you have a leak on the pressure side piping. Should be an easy fix.
you can buy intake leak testers ~$30 or so. just take off your air filter, clamp it to the piping, hook up an air compressor and the whole piping will be pressurized. Just have to listen for some leaks or run soap on the connections and look for bubbles....
I made a leak detector for my twin turbo setup. We clamped two PVC hose caps onto the inlet of each turbo, and one more on the charge pipe right before it goes into the TB
We also drilled one of the caps, got the area around the hole really hot and threaded a air compressor fitting in and let it set. Once that was done we set the compressors pressure regulator at 40psi and plugged it into the turbo and found all of our leaks, 2 of them we would have never found no matter how much we looked with other methods, and there was at least one obvious one, and one on a poorly welded piece of mild steel that was getting replaced.
We also drilled one of the caps, got the area around the hole really hot and threaded a air compressor fitting in and let it set. Once that was done we set the compressors pressure regulator at 40psi and plugged it into the turbo and found all of our leaks, 2 of them we would have never found no matter how much we looked with other methods, and there was at least one obvious one, and one on a poorly welded piece of mild steel that was getting replaced.
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Verdad Gallardo Thread Starter
TECH Resident
Joined: Jan 2004
Posts: 832
Likes: 0
From: Castro Valley, CA
Just to update...
One of the most simple vacuum reference lines that connected to the BOV had come off... and I'd missed it. And it was found in about 5 seconds at the shop. Nice.
Anyway, the summary would be: if you suddenly lose boost, but not all of it, and you don't come down to wastegate pressure, you're probably bleeding through your BOV.
Thanks to Josh at Newtech for making me look really stupid.
One of the most simple vacuum reference lines that connected to the BOV had come off... and I'd missed it. And it was found in about 5 seconds at the shop. Nice.
Anyway, the summary would be: if you suddenly lose boost, but not all of it, and you don't come down to wastegate pressure, you're probably bleeding through your BOV.
Thanks to Josh at Newtech for making me look really stupid.
Better to look stupid on an easy fix than perfectly diagnose a thrown rod...
Glad it turned out to be something simple. Reminds me of driving on 280 when all of a sudden big clouds of thick smoke started pouring out from the hood. Open it with fire extinguisher in hand, and all it was was the power steering hose had popped off its filter and squirted around. Fixed it right there and went to Kragen, got some rags and cleaner and fluid and was back in business.
Thought for sure I had somehow blown the motor.
Jim
Glad it turned out to be something simple. Reminds me of driving on 280 when all of a sudden big clouds of thick smoke started pouring out from the hood. Open it with fire extinguisher in hand, and all it was was the power steering hose had popped off its filter and squirted around. Fixed it right there and went to Kragen, got some rags and cleaner and fluid and was back in business.
Thought for sure I had somehow blown the motor.
Jim
Mite I add if I was you I would zip tie(hose clamps work better) all the lines that can blow off. I had some probs with my festiva went through and did this and all was good.