ratedZ Posted May 13, 2002 Share Posted May 13, 2002 Hey guys....recently I have noticed that my boost levels do not stay consistant. For example: driving it last night I've noticed that she's only boosting 8psi. So I go out and do the adjustment on my Dawes Device boost controller and dial it in to boost 12psi. Everything is ok then I noticed today while driving that the boost level has gone back down to 9psi. I haven't re-adjusted it back to 12psi because I wanted to know what would cause this. Also, not sure if this is normal but I can't hit 12psi unless I'm in a lower gear at WOT. Like if I punch it while rolling at 3rd gear I would only get about 10psi and would start to taper off into the lower numbers. I was thinking that maybe the spring in the controller was settling and that I would have to make the necessary adjustments accordingly.........thanks for your help guys! Quote Link to comment Share on other sites More sharing options...
Guest Tim78zt Posted May 13, 2002 Share Posted May 13, 2002 I'm pretty sure that the fluctuating is not being caused by the Dawes. I would put it back where you had it before you noticed this trouble. Then look for sources that may be bleeding boost off like the wastegate, BOV, IC, or even the guage itself. I installed my Dawes and have never touched it again. The spring does not settle. This thing is rock-solid. I'll bet you'll find the trouble in a leak somewhere in-line. I predict it is a leaky diaphram in the wastegate actuator (but I'm no psychic!!). Tim78zt Quote Link to comment Share on other sites More sharing options...
ratedZ Posted May 13, 2002 Author Share Posted May 13, 2002 I just checked all the hoses around the turbo area and everything looks ok.The controller is hooked up next to the waste gate so I know it's not because the vaccum hoses are too long. The hoses for the boost gauge looks good as well and I think the gauge is pretty accurate because the car is not overboosting....I'm sure if it was my Air/fuel meter will tell me or a piston flying out of the hood would also be a good indication lol. Very weird problem....any other ideas? Thanks. Quote Link to comment Share on other sites More sharing options...
ratedZ Posted May 13, 2002 Author Share Posted May 13, 2002 "I predict it is a leaky diaphram in the wastegate actuator (but I'm no psychic!!)" oh god I hope not! I have an extra turbo with the wastegate but have been putting off the swap because of the difficulty level. aaaarrrghh! Quote Link to comment Share on other sites More sharing options...
ratedZ Posted May 13, 2002 Author Share Posted May 13, 2002 ok...just got back from looking at my POV. I just noticed that two of the 4 washers I have on there is thinner than the other two. Maybe just maybe, it's venting from the POV at WOT and I'm just not hearing it. Soooo....I replaced the two thinner once and I will know if this was the problem after work. *crossing fingers* Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted May 14, 2002 Share Posted May 14, 2002 DO you have the factory waste gate actuator? If you do, it sucks. I have a dual port one from Top End on my hybrid, and it rocks. The only time I ever had a boost drop like you describe is when my turbo started going south. I had some contact between the compressor wheel and the housing. You may want to check that as well. I hope it is the actuator. Quote Link to comment Share on other sites More sharing options...
Sean 83ZXT Posted May 14, 2002 Share Posted May 14, 2002 I'm not too sure about the POV issue. When my would open I'd experience a spike and then it would open and power goes down DRAMATICALLY. You will definitely know when it opens. Mine started lowering in boost and shortly there after I was getting oil out of my BOV. Hope that's not it but I'd look into that. Quote Link to comment Share on other sites More sharing options...
Guest Cusp Posted May 14, 2002 Share Posted May 14, 2002 You can test your POV by putting a rubber glove over it, secured with rubber bands, and gunning it with the hood up. If it blows up at all, then you have boost-bleed. Quote Link to comment Share on other sites More sharing options...
ratedZ Posted May 21, 2002 Author Share Posted May 21, 2002 Well guys I figured it out! I modded the POV like normal but when it came to add more washers the center part of the POV (which looks like a cylinder) sat too low so I couldn't add any more washers. Soo the only logical step to take was to slightly hammer the cylinder up a little so I could add another washer or two. Well it turns out that in doing so I forgot to make sure that the cylinder/retainer sat flush with the washers....so when high boost kicked in, it pushed up the washers in the POV to compensate for the slack which then acted as a vaccuum leak. I finally figured this out two days ago...smacked my self in the back of the head and hammered the cylinder to sit flush with the washers. Now she boosts all day long at 13psi. It must have been just enough to let air out because I didn't even hear anything escape the POV at WOT. So if anyone else runs into this problem make sure that the cylinder/retainer sits flush with the washers. I know I derserve it Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted May 22, 2002 Share Posted May 22, 2002 I had my POV shimmed with an extra spring (VG motor remember) it worked great to about 10-11psi.. I could not find an adjustable one for a VG motor. MSA discontinued it.. Anyways..I'm boosting more than that now..so what did I do?...rather drastic "Tim the Toolman" fix.. I simply hacksawed it off right to the nut part.. put a washer over the last bit of hole opening, and welded it up solid..hehe not the smartest thing to do..but I'm conservative with my boost. HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA. boost creep..I had probs with boost loss. I could not get full boost till 3rd gear or higher.. ended up swaping the diff out to taller gears (smaller numerically) figuring it was lack of engine load. Seems ok now.. Yea Yea.. I know.. Amateur.. But I can rebuild, Jet and Tune a weber DCOE with my one hand tied behind my back....ok ok my ego is ok now....hehehe Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted May 22, 2002 Share Posted May 22, 2002 IMO, if you are really stuck on that POV (POS), the best way to make it work is put more spring in it, not washers. Every washer you put in there will limit the travel of the plunger - I found with mine it would not keep 12 psi, the boost would rise as RPM did (hybrid turbo, not stock). Also, it was quiet so I couldn't really tell when it was venting. The spring from a 200SX turbo POV worked very well, and if you need a little more margin, the POV can tolerate 1 or 2 washers. Quote Link to comment Share on other sites More sharing options...
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