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DR1 SC in dutch land
#21

I did check elbow 3'' inch one , and the hoses , all installed correct , so no problems there .



I'll check the vacuum to the heater later this evening , maybe something wrong there , i do have the heat coming up a bit when going over 140km for a while , there is a one way valve in there to the reservoir as well , i'll disconect it and run it pluged up , see iff i changes things .



Keep YA ALL posted
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#22

no worries.



it really sounds like a boost bleed off issue though. like i said, it it quite possible that one of the vacuum lines is not sealed up, and boost is going where it shouldn't. this would cause the blow off valve to act oddly.



the heater control valve hose could be the culprit. when that leaks or is disconnected, the heater comes on.
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#23

I checked all vacuum lines , also disconected the one used for the heater .



I am also for 99% convinced it is the blow off valve generating the noise .



I checked and cleaned and made sure there is no obstruction in one of the 3 hoses conected to the 3"inch elbow , all are clean and fine .



There is no difference , still the same .



I seems to me that , the blow off valve is kind of in between open and close and starts making the sound thru the inlet , kind of viberating .





Maybe i should drive a little more spirited <img src="/forum/images/smilies/968/3gears.gif" class="smilie" alt="" /> , since it only makes the soud when driving slow and low in the rev's
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#24

[quote name='tamathumper' timestamp='1352118160' post='134427']

Mine makes no noise sitting on the shelf <img src="/forum/images/smilies/968/sad.png" class="smilie" alt="" />

[/quote]

What is holding you from the install ???
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#25

it's not obstructions in the hoses i am looking for. it's kinks which would reduce the diameter and pinch off flow. those hoses are a bit of a bear to get routed so that they don't kink.



the blow off valve should make no noise. disconnect it and plug the vacuum line and see if it still does it. do NOT go to high boost like this.



i still don't know what boost readings you are getting, and i still think you have a vacuum leak somewhere, but try that first.
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#26

[quote name='flash' timestamp='1352147144' post='134448']

it's not obstructions in the hoses i am looking for. it's kinks which would reduce the diameter and pinch off flow. those hoses are a bit of a bear to get routed so that they don't kink.



the blow off valve should make no noise. disconnect it and plug the vacuum line and see if it still does it. do NOT go to high boost like this.



i still don't know what boost readings you are getting, and i still think you have a vacuum leak somewhere, but try that first.

[/quote]





I wil not be able to get you a boost rating , do not have the tool to do so .



Just to confirm from top to botom elbow , big hose goes to blow off valve , the next one is the idle control valve , then the breather hose .



The breather hose is made of really flexible stuff , right . i thougt it might be collapsing but there is possitve pressure in there coming from the crankcase , so that is not it either .



I'll try disconecting the blow off valve tommorw , see if the sound is gone .



No kinks in the hoses
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#27

hmmm - many vacuum gauges also have a positive pressure side, which you could use to see how much boost there is. hard to tell if you have bleed-off without that.



hose order correct. how much pressure is at the breather hose? it should be very little.



it's the ICV hose that i would be worried about having any kind of kink in it. if that is at all pinched, you won't get enough air in there when you need it.



just because you have a good reading at idle on the vacuum gauge, does not mean that you don't have a vacuum leak. there are a few places you could be leaking vacuum, and still not show it on the gauge (pretty annoying actually). you actually have to check each and every one of them. some will be straight vacuum. some will be ported.
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#28

[quote name='flash' timestamp='1352149475' post='134451']

hmmm - many vacuum gauges also have a positive pressure side, which you could use to see how much boost there is. hard to tell if you have bleed-off without that.



hose order correct. how much pressure is at the breather hose? it should be very little.



it's the ICV hose that i would be worried about having any kind of kink in it. if that is at all pinched, you won't get enough air in there when you need it.



just because you have a good reading at idle on the vacuum gauge, does not mean that you don't have a vacuum leak. there are a few places you could be leaking vacuum, and still not show it on the gauge (pretty annoying actually). you actually have to check each and every one of them. some will be straight vacuum. some will be ported.

[/quote]





I'll see if i can find a gauge that will show boost as well .



Breather hose has just i a little air coming out , i think compared to other ones i have seen felt , normal , would take a lot of time to dry your hair with that .





I am done for the day , i'lll get on it again tomorrow .
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#29

no worries - we'll track it down. might be a defective blow off, though i doubt it. we're not running enough boost or generating enough heat to mess up one of those
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#30

Flash : ran the car with the blow off valve disconected , sound is gone , so it is the blow off valve making the noise a 100%



Could you explain the way it should function in this system ?



Seems to me that there is vacuum to much at partial throttle and activating the boostvalve ,



I will dig in the vacuum part a bit more , see if i can find a leak , but a leak would be doing the opposit , closing instead of opening the blow off .



Also i wil go over all the hoses again .
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#31

i'm going to drive mine today and listen carefully
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#32

You should get out more <img src="/forum/images/smilies/968/rock.gif" class="smilie" alt="" />

Could you confirm that the blow off valve should be open when at idle and comming of the throttle after accelerating , and for the rest it should be closed ?
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#33

it should be open under vacuum and closed under boost.
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#34

Oke , i think i have a problem with the blow off valve .



After disconecting it sound was gone , connecting it again the sound was gone and it stayed away for about 3miles , the i parked the car and i really could not believe it .



So i opend the hood had a look around and scratched my head , got in the car and started on the glovebox to check vacuum hoses behind there , and found the problem with the rising heat , has nothing to do with the vacuum .



But i started the car up and reved it up , plop it said and the caped off part where the breather hose was connected before to the throtlle body came off and the car stalled ,i did rev it about 4500rpm before i came of the throttle .

Put i back on and went for a drive , and yep noise was there again .



So my guess there is something wrong with blow of valve , is there a way to check operation , can i just put an other one on there ?

Would not be the first time with a new part .

At least when i change it i can rule out the valve . before i start tearring things further appart
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#35

Check the vacuum reading at the end of the hose that connects to the blow off valve
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#36

[quote name='flash' timestamp='1352230889' post='134493']

Check the vacuum reading at the end of the hose that connects to the blow off valve

[/quote]





17.4"inch









Oke , i did something silly but i works .



First i disconnected all the vacuum lines also the ones under the manifold , took the rubber elbows etc off , checked all for leaks and obstructions .

Did not find anything wrong with any of them , put everything back , same noise .



Took the blow off valve off , looked checked operation , and found when it was retracting (opening(vacuum applied) is was not doing it in a square way , so one side opens quicker then the other , same goes for when it closes .



So now the silly part , i put it back the other way around , so the vacuum part is faceing sideways instead of downwards .

And the SC air is not pusing on the valve as before (helping it open )

It is not D1R like that , but it works , and most important the trompet like sound is Gone .



Also it gained power down low , i think because the valve is not opening and closing in a square way it is has trouble closing the last gap resulting in the anoying sound , and i lost some boost down low .



Downside is the design off the valve and the way it should be installed, it might not be opening as fast as it should because it is not supported by the boostpressure when opening .



Will put some miles on it and see what happens .





And wait for the doc Flash to see what he thinks .





Did about 20km , yes yes yes , perfect , no noise , better power down low , went up in the rev's just before the limiter comes in , no issue's no funny trompet noises , down low perfect and the boost valve seems to work fine this way .
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#37

weird. glad it worked though. it definitely sounded like you were bleeding boost. i'll have to think about this.
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#38

Flash ,do you still have a blow off valve in stock ?



If you do ,connect a hose to it and pull it vacuum (i used my motorcycle bleeder tool or suck on it (sorry for that ) ) and look the way the valve opens and closes , the one i have pulls to one side when i opens and closes .



I am done looking for vacuum leaks , there are none and i ran out of places to look for leaks , it has been all checked 3 times over .



The only 2 places i really do not know the way it should opperate is oil/air sepperator , the normal way(before SC) would be vacuum all the time would be my guess , now it wil have a little pressure on it from the boost exept with the throttle closed , could there be an issue there ?

Same is for the fueltank ventilation system , the ported vacuum is there , but no suction on the bigger hose down low left middle once there is boost .

Could it be i am loosing boost there , and creating a problem ?
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#39

i do have one from on of the yet unsold kits. i'll play with it today.



as for the vacuum issues:



the AOS is weird. there is a very small amount of constant vacuum off throttle. this is critical to its operation. the hose there must be the hard line, and not regular vacuum hose. otherwise too much vacuum goes through it, and you end up sucking oil. basically it provides a source of vacuum to pull the vapors and send them back to the intake via the breather. on throttle it goes out the breather, and again back into the intake. boost has not shown to be an issue, but a couple of us have installed a check valve just to be safe. i have no idea if it is really needed, but for $5 it seemed to calm my paranoia



the ported vacuum sources are not a concern.
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#40

I have driven the car a few times now since the BOV problem .



It is way stronger down low , and also fuel consumption is way better , went from 18 miles to 21 miles a gallon .

I think the bleeding of boost down low has been an issue from the start , and has been costing me some extra .



It is very nice that it's running the way it was intended , before there was also a kind hesitation when accelerating , only between 2/3000 rpm seems it has been the boost valve , it is gone now andy really smooth down low .



above 3000 rpm there is no difference was fine before and still is , it feels a little stonger as well but could be my imangination .



Can't wait to put the stage 2 stuff on there .
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