Boost gauge not showing boost?
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Boost gauge not showing boost? I have an AEM 30-4406 boost gauge and I haven't been able to get it to function right in the several months I've had it. I sent it back to AEM a week or so ago and they returned it with a new wiring harness. It never worked at all before I sent it back to them, neither boost or vacuum were showing up....
Now that they sent it back to me with a new wiring harness, it shows vacuum for the first time ever. However, it still isn't showing anything higher than 0, no boost is showing up on the gauge.
I know the turbo is building boost because I can hear the turbine spooling, feel the power, and hear a big "WOOSH!" sound from the BOV when I snap the throttle closed.....
I have the boost sensor installed in a vacuum manifold block, the manifold getting it's source or reference from a T fitting in the brake booster hose. I have 3/4" lines installed for the brake booster and vacuum manifold reference lines at said T fitting.
What am I doing wrong here?
Now that they sent it back to me with a new wiring harness, it shows vacuum for the first time ever. However, it still isn't showing anything higher than 0, no boost is showing up on the gauge.
I know the turbo is building boost because I can hear the turbine spooling, feel the power, and hear a big "WOOSH!" sound from the BOV when I snap the throttle closed.....
I have the boost sensor installed in a vacuum manifold block, the manifold getting it's source or reference from a T fitting in the brake booster hose. I have 3/4" lines installed for the brake booster and vacuum manifold reference lines at said T fitting.
What am I doing wrong here?
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Thanks guys, I will check for pinches in the reference line going to the manifold where the sensor for the gauge itself is threadded in. Also I'll put some compressed air to the sensor and see what it does.
This gauge might be bad..... Wouldn't suprise me after all the trouble I've had with it.
What's the reliability of a mechanical boost gauge overof a digital one like this? Any different?
This gauge might be bad..... Wouldn't suprise me after all the trouble I've had with it.
What's the reliability of a mechanical boost gauge overof a digital one like this? Any different? Trending Topics
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Ok I rerouted and straightened up the 3/4 hose which is my reference line to the vacuum manifold. Also found that the I/C pipe bewteen the turbo compressor an the IC itself had blown off, looks like I made that pipe a bit too short so I welded in an extension, nice and solid clamp now.
I still need to take off the sensor itself and apply a bit of compressed air to it to see what that does but I think the things I mentioned above have fixed it. I used the weakest springs that came with my WGs and so I'm seeing 1 to 2 MAYBE 3 # of boost when I get on it.
Also, I lowered the PE vs TPS enable tables to 30% across the board, made a few other fueling tweaks and WOW!!
This turbo really lights off now with some PE coming in much sooner.
The highest KPA I've logged so far is 135 I think, here is my latest tune and log.
Man that 30% TPS vs PE enable change REALLY woke thing thing up! I'm sure having the IC boot blown off didn't help either.... I know the factory tune had PE basically totally disabled with the 5000 RPM minimum RPM, timed delay, 90% TPS across the board...........
I still need to take off the sensor itself and apply a bit of compressed air to it to see what that does but I think the things I mentioned above have fixed it. I used the weakest springs that came with my WGs and so I'm seeing 1 to 2 MAYBE 3 # of boost when I get on it.
Also, I lowered the PE vs TPS enable tables to 30% across the board, made a few other fueling tweaks and WOW!!
This turbo really lights off now with some PE coming in much sooner.The highest KPA I've logged so far is 135 I think, here is my latest tune and log.
Man that 30% TPS vs PE enable change REALLY woke thing thing up! I'm sure having the IC boot blown off didn't help either.... I know the factory tune had PE basically totally disabled with the 5000 RPM minimum RPM, timed delay, 90% TPS across the board...........
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Might be a stupid question, but is there a check valve in booster hose? I thought the brake booster wasn't supposed to see boost. You might need to move the aem sensor to intake vacuum source. Mines in the back of the blower case and works perfect.
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well I don't think there's a check valve there, I read about many on this forum using that for a source. I have seen boost as high as 3# as of last night. I have the weak springs in my WGs for right now.
i cant tell you how many bad aem gauges I've seen as far as widebands I've seen. Not many boost gauges but those aren't as common. I'd say it's possible gauges go bad all the time when electronic. It's not hard to check though it take 10 minutes and could save hours of work
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My boost gauge is still working, shows vacuum as well as boost. I think I've seen boost as high as 6 lbs so far when I stay in it. Usually more like 2-4 PSI though...... I need to swap WG springs when I'm feeling froggy. Honestly, having never had something this fast I'm still adjusting to it! I know this low level of boost is nothing compared to some people but I'm still having way too much fun!
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My boost gauge is still working, shows vacuum as well as boost. I think I've seen boost as high as 6 lbs so far when I stay in it. Usually more like 2-4 PSI though...... I need to swap WG springs when I'm feeling froggy. Honestly, having never had something this fast I'm still adjusting to it! I know this low level of boost is nothing compared to some people but I'm still having way too much fun!