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Discussion Starter #1
I've been floating around the webs and this site trying to problem solve a p0299 issue I am having. A few months back I had my car in for inspection. It had a SAI CEL and my mechanic traced the issue to cracked PCV hardware. He ended up replacing most if not all of the PCV plastic bits and pieces as they broke during the repair process. The CEL went away and everything seemed fine. Shortly afterwards I realized that car had lost its get up and go (i.e. turbo). I tracked that down to a bad DV. I replaced the DV with a cheap Ebay one. The issue seemed to be cured and the car went back to running normal. After about two weeks I get the p0299 back but the car is running well with no loss of power.

So, I'm thinking that the cheap DV I installed is the fault, but I'm wondering if it went wrong, would I have a loss of power or too much power? Everything seems good. I check with boost using the Torque Pro App but I'm not sure how accurate that is.

Any suggestions would be helpful.

Thanks
 

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Not much else it could be besides a loose hose. Just enough to cause the code, but not enough to feel it. At least pull the DV and do a pressure check. Check all the vacuum lines as well. If you have a leak in a line leading to the DV, it will not operate as intended and the ECU could be seeing that.
 

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Discussion Starter #3
I climbed under the car today and checked all the connections around and to the DV. Everything seemed fine. Then I clamped the vacuum line running to the DV and the boost jumped up. Now I can't remember if that indicates a DV issue or a N75 issue. I swear I found tons of posts about that simple test and what it meant but now my search skills are leading me to more confusion.
 

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Possibly neither. Check the vac hose coming off the front of the intake where it snakes under the manifold to the N249 valve (If you have one. Earlier models had the intake manifold line run straight to the DV). That is what feeds the N249 vacuum which controls the DV operation. If there is a problem with the N249 or a cut in either line, you can get underboost. The the N75 which controls the wastegate does not share any vacuum with the N249.
98530

Edited to correct a false statement about vacuum on the N75
 

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Discussion Starter #5
Ah, that may be a lead. The press fit vacuum nipples were broken, one by myself and one by my mechanic. He replaced them by tapping the opening and putting in a brass screw variety. I'll check that one out, should be simple enough.
 

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for whats it's worth if I am not mistaken the wastegate diaphragm ,#24 in the above diagram operates off the turbos positive pressure.The turbo has a nipple (on the pressure side of the turbine) which goes to the N75 (controlled by the ECU), the other side of the valve goes to the diaphragm on the wastegate (sometimes referred to as the "penny valve")
 

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Discussion Starter #8
I found a few loose hoses related to the pcv system today. I tightened them down, but haven't taken the car out for any tests. I did however pull the codes again and I do have P0299 and P0411. I'm guessing the issue is related and possibly a vacuum leak somewhere but I'm just guessing. Suggestions are welcome.
 

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will pose this question ,if possible, is it known at what the temp. was when code appeared, as combi system is only active from like 39f to 90f. ,possible hole in combi diaphragm or vac. hose ? OP from upstate NY.... Gonna order hose from Amazon today as a backup to my original,just a matter of time you know.......
 

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Discussion Starter #12
Those hoses are pretty poor quality. I'm in Western NY and I've resorted to zip ties to keep it tight to the SAI pump. Still seems tight so I don't think that's my problem. However I'd like a better quality hose.
 

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OK, so the vacuum provided to the N249 is also shared with the N112 controlling the combi valve for the SAIP.

There can be two areas to check there. The shared connection of those two valves (the hose is shaped like a capital "F") or the vacuum source connection to the intake manifold.
 

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Discussion Starter #14
Would that be the vacuum line shown just to the left of the solenoids in the diagram?
 

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Yes and it gets it's vacuum from the vacuum reservoir and the L hose. It's possible that a section was damaged during the PCV repair. The one way valves get very brittle from heat.
 

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As a sidebar to this, the N112 and N249 although labeled/numbered differently are identical parts.... with that said I remember there is a plastic tee fitting in that bucket of worms underneath the intake manifold that I struggled with in there to chase down a vacuum leak , it appeared good but fell apart upon examination as mentioned previously, the plastic became brittle and cracked do to heat
 

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Discussion Starter #17
I'm still chasing this issue down. I'm "fixing" any connections I find possibly loose. I reset the CEL and it did take 24 hours to come on instead of a few hours, so that must mean progress.
 

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ambient temperature may be a factor as the SAIP system does not activate below 39 f degrees, so the N112 may have never came on, or came on only as temperatures increased during the day in your location. As a suggestion see if your combi holds a vacuum.
 

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Discussion Starter #19
So here's the latest and a solution. First the solution - I pulled the vacuum hose off the air intake that runs to N249 and discovered there was not vacuum. So I took a bit of wire and poked down the nipple and sure enough there was something clogging it. Whatever it was came clear and probably got sucked in somewhere I wouldn't want it. So I reconnected the hose and reset the CEL. The CEL did not come back on for days. Second Issue - I checked the CEL and got code P0411 only. So I think I fixed one and need to still chase down the other, but I'm guessing they are somehow related to leaks from all the PCV system work that was done.
 

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P0411 is a SAIP error (secondary air injection pump).

Two of most common causes are:
The vacuum line to the combi valve is leaking, thus the valve isn't opening
The 373 relay in the ECM box (not under the dash) has burnt contacts and thus the pump (blower) isn't running. (Or sometimes, the relay stick closed and the pump runs your battery down, but that doesn't cause P0411...)
 
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