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Still chasing a low boost problem, any suggestions?
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12-18-2007, 12:39 PM | #24 |
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I unfortunately do not have a boost gauge, but I will soon. IMO a turbo car w/ out a stock boost gauge is stupid. Should have been my 1st mod.
the shop i'm going to soon has a boost gauge that he will slap on for the dyno runs in stock and V2 config so we will see what its doing. By the way......WHAT PSI SHOULD i SEE W/ THE BYPASS PLUGS IN??
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12-18-2007, 12:43 PM | #25 | |
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Stock boost level. Five to eight depending on temp.
Also, have you pressure tested the core? I have seen some EVO ICs come with pin hole leaks. Quote:
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12-18-2007, 01:47 PM | #26 | |
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I have not, that is one of the next steps i'm ready to take. I really hope that isnt the cause considering I just put that thing in. Thanks for the answer on the psi
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12-18-2007, 01:59 PM | #28 |
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12-18-2007, 02:04 PM | #29 |
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Judging by the amount of missing boost (Assuming boost is missing) I would think it would be pretty audiable. The only other quick check I can recommend is to hook up the Proceed (leave the cowl off the car) and gun the car with a high target boost next to a long wall/median with the window down and listen for the leak. It will sound like an airhose "SHhhhhhhhhh"
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12-18-2007, 02:21 PM | #30 | |
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Havent heard anything yet, there was an audible pssshhhhh when I first put in the intercooler, forgot to tighten down the stock worm clamp on one of the pipes. After that I have not heard as much as a peep. It will be on a dyno soon, so standing next it i'm sure I will hear any major leaks. hooking up a mechanical boost gauge and seeing those readings vs the procede's software is the next step.
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12-18-2007, 02:29 PM | #31 | |
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12-18-2007, 03:00 PM | #32 | |
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12-18-2007, 03:19 PM | #33 | |
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Ahhhh, you lucky SOB, im so jealous, there are only a few spots here or there on long island where i live that is even remotely secluded.......nice pic brotha |
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12-18-2007, 03:29 PM | #34 |
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So the fact that it is 25F has nothing to do with low boost? Like i said, when its 35F outside at night in my area i dont boost past 10psi until i get the car hot or it gets warmer outside... I also have a new FMIC... Could the FMIC and low temp have anything to do with the low boost?
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12-18-2007, 03:36 PM | #35 | |
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12-18-2007, 05:45 PM | #36 |
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I would think that the ECU thinks its reaching boost target, otherwise the turbos would continue to spool which I would think be an audible noise and also throw a code for not reaching boost target.
You mentioned earlier that you heard a noise when something was loose, is it possible that the ECU recalibrated itself during that episode? Maybe you need to reset the ECU somehow. |
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12-18-2007, 05:47 PM | #37 | |
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on a side note: DO NOT SHUT YOUR TRUNK AFTER UNHOOKING THE BATTERY!!!!
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12-18-2007, 08:11 PM | #38 |
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Ok never made it to the dyno this afternoon, pretty frustrated w/ the guy at the shop, he didn't call me back!
I ran around all day w/ the bypass plugs in, no codes were thrown, car ran fine and felt strong for stock. Put the V2 back on at 92%, went out and ran these logs. its loosing psi at the higher rpm's were it seems that most people logs are showing steady or climbing boost at the higher rpms. I won't post anything else until I get this car on the dyno to test boost w/ a gauge as it seems I'm wasting my time just making new datalogs that keep showing the same thing. run 1, 3rd and 4th gear, seems that i'm at 10psi consistently at 5500rpms in 3rd or 4th gear and then dropping boost from there. Even 10psi is too low though, but once again the ambient temps were around 30 degrees. This was a 1st thru 4th gear, you can see me pedaling 1st w/ no traction.
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12-18-2007, 08:17 PM | #39 |
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This is interesting as it shows 2nd gear having near normal boost, 3rd looks like what you have had and 4th looks normal considering the temperatures.
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12-18-2007, 08:18 PM | #40 |
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It looks like you're being held back from making more boost, not a boost leak. The little ups and downs look like "throttling". I'm just speculating though, get the boost gauge on there man.
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12-18-2007, 08:23 PM | #41 |
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Ya, the 2nd gear pull with the boost climbing towards the higher revs does not appear to be a boost leak. If there was a leak and with the quicker consumption rate in the lower gears, I would assume 2nd would show lower.
Then 4th looks relatively normal considering the temperatures. Since no codes or limp modes occured with the bypass plugs in and I assume you did push it, a boost leak is most likely NOT the case. Now, what happens when the settings are brought up to 94% or 95%? |
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12-18-2007, 08:28 PM | #42 |
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I'll test at 94% tomorrow if I can, I've had a few Samuel Smith's already this evening so no more full throttle backroad blasting for me.
I did notice 2nd gear felt stronger and more "urgent" while the 3rd and 4th felt more lazy. In the last 1000 rpms of 4th in the 1st log the boost is dropping below 8psi......that is almost stock levels. Its puzzling me. I'm starting to suspect the diverter valves having problems with higher boost (stock its fine?), but at this point its pure speculation. The forge units are en route however! If I have to end up designing a true boost leak test "kit" I'll be sure to document it thoroughly, to the best of my knowledge no one else has had to do it and i'm sure someone else will have to do it after me.
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12-18-2007, 08:35 PM | #44 | |
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Might amend this to don't shut your keys in the trunk after disconnecting the battery Nice picture btw...I need to find a nice wide open stretch like that around here |
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