Bossman429 Posted December 5, 2004 Report Share Posted December 5, 2004 After helping as many people in the General section with vacuum leaks, I finally decided to try to track down my vacuum leak in the STE. I installed a new check vavle, a LOT harder down under the turbo than it was on the Beretta back by the firewall. I had a vacuum gauge trying to track down a leak, I plugged the gauge into the 2nd hose from the left coming out of the harness on the back ob the T/B, I noticed it was the only one of the 4 lines not holding pressure, it is also the one which feeds vacuum to the HVAC, or the heater controls. As I applied vacuum I could hear a whistling noise coming from somewhere around the turbo. I decided to test the vacuum ball for pressure, I followed the line up through the side of the battery, and SURPRISE! the line coming up from the vacuum ball is plugged into the system. I tested vacuum on the line just to be sure that the line and vacuum ball aren't leaking, which they arent. So the problem seems, where does the vacuum ball plug in at? I have a hose that reaches to the cruise diaphram, and there is a factory "T" in the line that divides the vacuum from the T/B to the HVAC, and Cruise. There is a second "T" that ISN'T factory and I'm not sure why it's there, like the previous owner spliced it in for some reason. I think the area where those two "T"s are is where the ball should plug in at. these "T"s are on the passenger side of the cruise diaphram. Could someone else with a TGP take a look at theirs and throw be a bone here? I would have posted in "General" but the turbo vacuum diagram is SO much different from the N/A vacuum system that I fear it wouldn't have been much help. Any replies appreciated. Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 5, 2004 Report Share Posted December 5, 2004 Think it better to just give a pic 8) http://www.turbograndprix.com/new_page_1.htm BUT you will have to look at the very last pic on that page!!! From there you will see the vac canister, running to the check-valve, which braches up to the short run with a 90 to the cruise, and the other line/upper to the vacuum block behind the engine block by the firewall which is the source for your vacuum/engine vacuum feed which is from one of the line coming off the top of the TB, then the lower line that starts off from the check then disapears into a wire loom running through the firewall to your HVAC System. Make sure your check-vavle does "check", and that all lines in this area check out like in the pic and that should get you a lot further along, good luck! Jeff M Quote Link to comment Share on other sites More sharing options...
Bossman429 Posted December 5, 2004 Author Report Share Posted December 5, 2004 Thanks Jeff, that helped a lot, but now makes me wonder just how rigged up the vacuum system is on this car, as I just bought it a couple weeks ago. The pic that caught the most of my attention is that of the 8th pic down, after the tubo comparison pic. The pic appears to be the check vavle that is attached near the bottom of the turbo. I replaced it yesterday, because I thought it would be cracked, as that's usually what happens on these 3.1s. Oddly enough, I plugged it in the way I took the old one out. However, that pic you have shows the 90 degree split out of the check vavle,this matches my car correctly :? mostly. The one hose comming straight out the smaller end goes to a metal line, which leads to the top of the engine and into the T/B. The other plugs into what looks like a regulator on the turbo with a short 1 inch hose. My quandry comes in the other nipple on that check valve. On your pic it says "No vacuum line attached to pressure exhaust fitting." Why does this cause question? Because on my car there IS a line coming off of that nipple, it runs up to one of the "T"s near the cruise. Could this be some sort of rigging that the previous owner put on the car? What does that check vavle on the bottom of the turbo do? and is there supposed to be another check vavle in the system? Is that a 2 way check vavle in your pic just before the line splits into the upper and lowwer hose. The more I look at those pics the more it is starting to make sense. I'm almost wondering if that line that is coming off of the "pressure exhaust fitting" is really supposed to be connected to the vacuum ball. Thanks for you help, I'll have to go take a look at the car once it stops raining Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 5, 2004 Report Share Posted December 5, 2004 Damn what a mess !! Sounds like the lack of vacuum (that you have now fixed we hope) to the HVAC System was “fixed†by the thought that stealing vacuum from the check-valve under your turbo (not on your turbo, at least I hope not, more on that later), which was thought a source of vacuum (on that bleed port), but is only a true vacuum source if the check-valve is leaking ! Since pictures do not lie, yank that hose from the check-valve under the turbo that runs over to your other vacuum lines under the cruise control area, and block that port of the new “T†they stuck in there or take it out, now follow the pics as its shows the way your lines are supposed to be! Now as for the check-valve at your turbo, better not be one!!! This check valve that is feed from that metal line coming from the upper intake behind the throttle body is hooked into what is called the Transmission Vacuum Modulator/TVM! The “check†also bleeds boost so that the TVM does not receive boost, but will “check†when a vacuum is applied (and so you don’t have a vacuum leak too). And yes this is the same check-valve you see in the pic with all the lines that split and the vacuum reservoir there. So just to make sure, the pic of the check-valve at the TVM is supposed to be open to atmosphere to bleed boost and not be blocked or hooked to anything else!! The turbo has an outlet boost pressure port at the outlet of the turbo’s compressor; brass fitting, that has a vacuum line that runs up to the solenoid on the top front of the upper intake, then from there another vacuum lines runs from this solenoid over to the top of the turbo wastegate actuator, that’s it. Now digest this and let me know what’s left, got to run and wash, gas the woman’s car then get on swapping off the summer tires to winter snow tires . Jeff M Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 6, 2004 Report Share Posted December 6, 2004 Ok.. that 8th picture.. Where is that supposed to be at again? I've never seen anything like that on either mine or Jess's TGP's. Her car has an aftermarket vacuum ball on it (some goofy looking red thing), and the vacuum lines were a mess from the beginning when she bought it. I may have to get pictures to show. Quote Link to comment Share on other sites More sharing options...
Bossman429 Posted December 6, 2004 Author Report Share Posted December 6, 2004 That 8th picture is on the bottom of the tubo, near where the oil return line goes down to the oil pan. The short line (pointing to the right in the pic) actually plugs into a regulator looking thing near the bottom of the turbo amidst the tangle of upper rad hose, and intercooler pipes. The pic is a view of it if you were looking at it from the drivers side. BTW: Thanks for all of your help Jeff, I got it all plugged in correctly now, I wouldn't have been able to figure it out without this forum. I need to install the spare check valve I have at work tommorow in the spot shown in your last pic, I'll run new vacuum lines to try to organize that mess that was the rigged up vacuum lines. Working in a warm shop beats the hell out of working in the rain 8) Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 6, 2004 Report Share Posted December 6, 2004 Luke and B-Man, take another look, just below the drawing of the TVM is a pic courtesy of James pic files 8) Glad to help B-Man (if you don't mind me calling you that?), I know how frustrating working on a car you never touched before let alone seen much of how its supposed to look can be! Luke I hope this answered your question too? Jeff M Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 6, 2004 Report Share Posted December 6, 2004 Great picture! There is NO such a check valve on her car like that. It would probably be good measure to get one installed eh? What kind of problems can be caused by not having that check valve there? The only thing plugged in to the vacuum port on the tranny is the rubber fitting for the steel hose that goes to the TB. That check valve goes in between that steel hose the the tranny right? Mine obviously has no such a connection since the 282 doesn't need a vacuum source. Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 6, 2004 Report Share Posted December 6, 2004 Yea, WOT tranny shifts are pretty hard. She takes it easy on the car, so it hasn't been a big problem. What kind of check valve do I need to look for? Anything special? Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 6, 2004 Report Share Posted December 6, 2004 WTF? What happened to your post Jeff? And why was my reply posted under your username?? A glitch in the matrix! :shock: Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 6, 2004 Report Share Posted December 6, 2004 WTF? What happened to your post Jeff? And why was my reply posted under your username?? A glitch in the matrix! :shock: Double-WTF??? Guess I read your mind/question? You got me though, I did nothing :shock: Anyways (I hope!) good to hear she is easy on it, and can now get on the road to fixing on last little thing the previous owner(again with those damn "previous owners" ) messed with. That check-valve on the tranny was discontinued years ago, you can get one if you order the entire vacuum assembly for the cruise control but there has been a different version past owners have used/Shawn L suggested GM/AcDelco part number 14056648 for about $6 retail but it bleeds a little bit slower than stock, never heard anyone who bought it complain so sounds like a good alternative, just make sure to see which way this one "checks" as I think its backwards from the original one, it will still work turned around just fine!! Now, quit messing with my posts!!! (the "real") Jeff M Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 6, 2004 Report Share Posted December 6, 2004 So, before I buy something and install it wrong.. The purpose of this check valve is to allow vacuum and restrict boost from entering the modulator? Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted December 6, 2004 Report Share Posted December 6, 2004 The purpose of this check valve is to allow vacuum and restrict boost from entering the modulator? correct marcus Quote Link to comment Share on other sites More sharing options...
Bossman429 Posted December 7, 2004 Author Report Share Posted December 7, 2004 Well I got it all done today at work. Oddly enough we had a 90 Lumina and a 95 or 96 Monte with a 3.4 in the shop as well. I used the Lumina to get my lines all in the right spots and make sure the check valve was in the right direction, works great now. Feels good to have one more thing ironed out on the car. Also feels good when the heater blows out of the vents at WOT instead of moving to the defrost under low vacuum. Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 7, 2004 Report Share Posted December 7, 2004 David, I didn't realize that you were in Manhattan! Nice to see another Turbo GP close by. We'll have to meet up next time I'm there. Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 7, 2004 Report Share Posted December 7, 2004 Well I got it all done today at work. Oddly enough we had a 90 Lumina and a 95 or 96 Monte with a 3.4 in the shop as well. I used the Lumina to get my lines all in the right spots and make sure the check valve was in the right direction, works great now.Feels good to have one more thing ironed out on the car. Also feels good when the heater blows out of the vents at WOT instead of moving to the defrost under low vacuum. Yea urks you when the air changes locations when it wants to, and your cruise will work now too 8) . Lots of fixes to these cars are to fix the last "attempts" at repair. Over the years I have head some wild stories, one like an owner installing 19 lb injectors to fix the over-rich fueling from a cracked crossover, only to spin some rod bearings and destroy the engine later, so always good to come to these message boards for some suggestions 1st. AND THANKS for the feedback, very important to me hearing it worked, this confirms a problem's most likely fix (and sharing the success is rewarding too 8) !!) Better luck now!! Jeff M Quote Link to comment Share on other sites More sharing options...
Bossman429 Posted December 8, 2004 Author Report Share Posted December 8, 2004 David, I didn't realize that you were in Manhattan! Nice to see another Turbo GP close by. We'll have to meet up next time I'm there. Sounds like a plan! The drive from Manhattan to Hays HAD to be the most boring 2 hours of my trip to Colorado (Beretta Fest 2004) last summer. My girlfriend lives in Salina, so that's about as far west as I usually travel. Let me know next time you'll be around. I have a pic in my sig now too!!!!!!!!!!!!!!!!!! So I can burn my place in the W community, make my presence known. too bad my STE doesn't look as good as the Beretta, but I've have the Beretta for 4 years, and the STE for 2 weeks, so I must give it time. Gotta slowly iron out these kinks! Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 12, 2004 Report Share Posted December 12, 2004 http://www.lukez34.com/hostedpics/DSC03403.JPG Is that the correct style of check valve? I'm assuming the larger end is for the bleeding, and the other 2 connect to the plenum vacuum and to the tranny? Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 12, 2004 Report Share Posted December 12, 2004 http://www.lukez34.com/hostedpics/DSC03403.JPG Is that the correct style of check valve? I'm assuming the larger end is for the bleeding, and the other 2 connect to the plenum vacuum and to the tranny? That will work!!! Nice find!! Check for tranny fluid in the vacuum line too, good opertunity just in case the Vacuum Modulator is leaking/time to fix it Jeff M Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 12, 2004 Report Share Posted December 12, 2004 I don't think that is the correct check valve after I installed it. I installed it with the large end not connected to anything, and the other 2 smaller ends connected to the tranny and the TB vacuum line. The 2 - 1 downshift while coming to a stop was HARD. Like a jarring, loud clunk, hard.. so I removed the damn thing and put it back the way it was before (with no check valve) and it's fine again. I think I just need to order the one from GM as I don't think the cheap alternative that we bought was correct for this application. The tranny was rebuilt on this car a few years ago, and I'm wondering if they just forgot to put a check valve back on that vacuum line? I don't think the previous owner knew any better at the time. :? Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 12, 2004 Report Share Posted December 12, 2004 Well, if you installed like this: Then that should be right! BUT, look at how its setup in the pic, the port open should allow boost/air out, so put this thing in your hand, plug one of the ports that gets a vacuum line attached to it with your finger and blow on the other port that gets a vacuum line and air will blow out the port that is supposed to be open, suck and it should stop/"check", if it does these things then a GM unit will not be much different :? If not then turn the thing around so it functions this way/attach hoses and test on a short trip (don't need to drive a long way to see if it bangs in gear again). Also I said to check for tranny fluid since some owners have had the VM diaphragm develop a leak that also causes a harsh shift, what were your results in checking this!!!! Jeff M Quote Link to comment Share on other sites More sharing options...
LukeZ34 Posted December 12, 2004 Report Share Posted December 12, 2004 Yea, it was hooked up exactly the same way. I can blow on the vacuum port, and plug the port for the tranny and the air blows out the open port, and sucking it stops. I didn't see any tranny fluid inside the rubber hose I pulled off or anywhere around the vacuum modulator. I noticed a audible, fast clicking sound coming from that area of the tranny when I had the check valve installed. When I removed it the clicking disappeared. I have no idea what it was. Maybe the vacuum hoses were leaking around the check valve's ports? They seemed snug enough, but I guess it's a possibility. EDIT: Yea, it was leaking around the rubber hoses, that must have been the cause of the noise, and the shifting problem. Quote Link to comment Share on other sites More sharing options...
Jeff M Posted December 12, 2004 Report Share Posted December 12, 2004 Excellent , and good thing you were paying close attention to things and did not miss that little clicking/leaking sound, missing it would have sent you down the wrong road. Sweeeet, should be good to go now 8) !! And woman will be happier always a good thing Jeff M Quote Link to comment Share on other sites More sharing options...
Prospeeder Posted March 5, 2005 Report Share Posted March 5, 2005 http://www.lukez34.com/hostedpics/DSC03403.JPG Is that the correct style of check valve? I'm assuming the larger end is for the bleeding, and the other 2 connect to the plenum vacuum and to the tranny? where did u find that?? its just like the check valve for the cruise and hvac! like napa or autozone or shuck's or somthing Quote Link to comment Share on other sites More sharing options...
Jeff M Posted March 5, 2005 Report Share Posted March 5, 2005 Yea that "HELP" Brand is everywhere thankfully!! GM has the same but I bet this one is a little less in $$. There is a pic here below for the layout of the rest of the Vacuum Lines for Cruise/HVAC and such. Also Proboy, give me a chance to reply to your long PM, I am putting it into an email to better work on all your ideas and questions, I won't forget you!! http://www.turbograndprix.com/VacLines001.jpg Jeff M Quote Link to comment Share on other sites More sharing options...
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