Boost spiking despite having PFC Boost Control Kit installed
#26
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Thanks gentlemen, so things to do this weekend:
-Apply pressure to wastegate actuator nipple while pinching the other hose to ensure the rod moves.
-Drill precontrol and wastegate pills out slightly.
-Test precontrol/wastegate solenoids
-Apply pressure to wastegate actuator nipple while pinching the other hose to ensure the rod moves.
-Drill precontrol and wastegate pills out slightly.
-Test precontrol/wastegate solenoids
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I'm pretty sure that's what is happening though. I've watched it on the PFC during a pull and would keep building up, the highest I saw it cut at was 0.91kg/cm2, or 13psi. It never dipped down to a transition psi, just kept shooting up. That happened somewhere around where the transition point should've been.
#31
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Ok progress report gentlemen.
I swapped in a used precontrol/wastegate solenoid that tested correctly. While changing the old one out, I found what I thought might've been the source of my problems, one of the plastic nipples had broken off. Swapped in the good solenoid and it didn't fix anything. Still over boosting, this time boost was cut off a 0.95 kg/cm2.
So today I was able to test the wastegate actuator itself. I pinched the hose going to the rat's nest, and plugged my MityVac into the other nipple that used to go to the pills.
I started off by applying pressure and the rod started to move at 8psi, and was fully open somewhere between 12-14psi. I released pressure and the wastegate shut smoothly. I then applied vacuum up to about 25mmHg and let it sit for a few seconds, it did not leak at all.
So it seems the final step is to hollow out those pills a little bit. I'll be knocking that out next weekend.
I also managed to borrow the Datalogit, however he didn't have the software disk. Looks like I'll purchase my own if I can't find the software online.
I swapped in a used precontrol/wastegate solenoid that tested correctly. While changing the old one out, I found what I thought might've been the source of my problems, one of the plastic nipples had broken off. Swapped in the good solenoid and it didn't fix anything. Still over boosting, this time boost was cut off a 0.95 kg/cm2.
So today I was able to test the wastegate actuator itself. I pinched the hose going to the rat's nest, and plugged my MityVac into the other nipple that used to go to the pills.
I started off by applying pressure and the rod started to move at 8psi, and was fully open somewhere between 12-14psi. I released pressure and the wastegate shut smoothly. I then applied vacuum up to about 25mmHg and let it sit for a few seconds, it did not leak at all.
So it seems the final step is to hollow out those pills a little bit. I'll be knocking that out next weekend.
I also managed to borrow the Datalogit, however he didn't have the software disk. Looks like I'll purchase my own if I can't find the software online.
#34
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So got the Datalogit plugged in and what not then tried to log a quick run, man this one of those times I wish I had a reputable tuner on island. For whatever reason when I added watches for RPM, basic boost and etc., the values never moved. I recorded a short log that saved as a .txt file and a .dat file. Trying to look over the .txt file but I'm not really sure what I'm looking for here.
Reading, reading, reading over other threads. My head is spinning a bit.
Reading, reading, reading over other threads. My head is spinning a bit.
#35
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Hear me now and believe me later.
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
#37
Hear me now and believe me later.
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
If you unplug the stock precontrol & wastegate solenoid, and the engine is still overboosting, the pills are the problem.
#38
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Hear me now and believe me later.
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
YOUR OVERBOOSTING IS THE PILLS. PERIOD.
The factory boost control system was built around the factory amount of intake and exhaust restriction. As soon as that's changed, you'll get spiking and overboost. This is well known and documented.
Many moons ago when my car was closer to stock I had spiking with just a downpipe and a catback. I drilled the pills out a small amount to reduce spiking. Then, when I put an intake on, I had the problem again. I ditched the pills and got a good boost controller, never had a problem again.
The factory boost control setup is ONLY good on a STOCK car. This is also the reason why there's a LOT of blown FD engines out there - guys throw on a full exhaust and intake, boost spikes up, seems fast and fun, then you blow up the engine because boost is out of control. The FD's computer is just too old school to properly regulate boost.
Dale
Trust me good sir, I haven't ignored your advice. Just the other 2 things I tried this weekend were the least time consuming. I'll be drilling next weekend.
Thanks, I think I got it figured out after playing some more of the options.
#39
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Bit of an update, I finally got around to drilling the wastegate control pill with what I believe was either a 1/16 or 5/64 drill bit. The problem is still happening.
Should I bump up to the next drill bit size? I know it was mentioned before that I should be drilling it out very slightly. I might just go back to the stock intake at this point.
And just to double check the wastegate control pill is on the right side if you're looking at the engine head on.
Should I bump up to the next drill bit size? I know it was mentioned before that I should be drilling it out very slightly. I might just go back to the stock intake at this point.
And just to double check the wastegate control pill is on the right side if you're looking at the engine head on.
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So I went up a step on the drill bit sizes and went for another spin, problem is still there, but not as bad. Now I can atleast keep it down to .89kg/cm2 with the PFC being set up .65/kg/cm2. Note that the precontrol nipple is still untouched, only drilled out the wastegate control.
So now what's the next step? Admit defeat and just install the stock air filter? Try a different boost controller? Out of ideas now.
So now what's the next step? Admit defeat and just install the stock air filter? Try a different boost controller? Out of ideas now.
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I think in almost at the point if I drill again there might as well not even be a pill in there. Would there be any side effects to the pill being drilled all the way out if it comes that? Slower spool maybe?
I'll give it a go one more time.
I'll give it a go one more time.
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Well I went back and opened up the pill some more. Now on this test drive it shot up to .96kg/cm2.
Sigh.
I'm throwing the stock intake back in to see if that will tame it down.
Sigh.
I'm throwing the stock intake back in to see if that will tame it down.
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I'm at a loss. Still boosting way high even with the stock air filter box. Note the only mods installed right now breathing wise is hard pipes for the intake and intercooler, and a cat-back. I also realized the only reason it stopped at .89 last time was because I have the PFC set to cut at .60, it then cut off at .96 when I had it set to .65. So no real progress is being made here.
I guess back to the drawing board on testing everything. I'm out of ideas.
I guess back to the drawing board on testing everything. I'm out of ideas.
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Shouldn't be, I replaced one of the lines which for sure doesn't have a pill. The other one shouldn't, but it doesn't hurt to double check. Other than that, those 2 lines are now y-piped into the new boost solenoid from the boost control kit.
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No pills in any lines. Wouldn't happen to know which colors wires go to which plug on the wastegate/precontrol solenoids do you?
It's a long shot, but I'm wondering if somehow they got mixed.
It's a long shot, but I'm wondering if somehow they got mixed.
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I can also confirmed that the wastegate does open under pressure, and doesn't leak under vacuum. I can see the actuator rod opening at around 8psi, and is fully open at around 12.5psi.
That's pressure being applied with a MityVac, I wonder if something in the system isn't applying that pressure. Or that other port isn't being closed shut allowing pressure to escape. I'll have to trace where that other line goes and see what's
up...
Edit: That other line runs to the wastegate/precontrol solenoid, which I previously tested to be good...guess I'll be trying to acquire another one for testing.
That's pressure being applied with a MityVac, I wonder if something in the system isn't applying that pressure. Or that other port isn't being closed shut allowing pressure to escape. I'll have to trace where that other line goes and see what's
up...
Edit: That other line runs to the wastegate/precontrol solenoid, which I previously tested to be good...guess I'll be trying to acquire another one for testing.
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I believe I've made a breakthrough, or atleast band-aided the problem.
I started adjusting my boost duty cycle very low to see what happens, and so far %26 duty (which I know is super low), it was at a steady .87kg/cm2 with a setting of .70.
Also what I think might actually solved the problem was that the hose going the wastegate control nipple on the primary turbo didn't have a clamp at all and I never thought twice about it because it was a snug fit. However the last thing I did was cinch a zip-tie on it really good just to see what happens. I wonder if that hose was kind of letting air escape? Who knows, but as of now my max boost is looking stable.
I started adjusting my boost duty cycle very low to see what happens, and so far %26 duty (which I know is super low), it was at a steady .87kg/cm2 with a setting of .70.
Also what I think might actually solved the problem was that the hose going the wastegate control nipple on the primary turbo didn't have a clamp at all and I never thought twice about it because it was a snug fit. However the last thing I did was cinch a zip-tie on it really good just to see what happens. I wonder if that hose was kind of letting air escape? Who knows, but as of now my max boost is looking stable.
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