ryan95i4 Posted October 1, 2012 Share Posted October 1, 2012 Since I sort of piggy-backed on 240z7273's thread, just wanted to follow up and found my issue was caused by loose pins in the ECM connection -- have gone through all the pins and fixed as needed and solved my issues. Even though we had similar symptoms, dont know that we had the same problem. Quote Link to comment Share on other sites More sharing options...
240z72 Posted October 2, 2012 Author Share Posted October 2, 2012 No we dident have the same problem. I went over the ecu connections many times..i will never know what my issue was. The car was sold and motor was tore out. Aparrently the motor blew shortly after i sold it. One problem was too much aftermarket stuff on stock ecu. I will never buy a bad running swap again thinking well shoot i can fix that haha. Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 3, 2013 Share Posted February 3, 2013 This is most likely not the cause but worth a shot, I have a L28ET as well and was having real bad sputtering that progressed to the point where it would die. After looking all over I found that the gasket that is under the spring in the pop off valve had shifted enough to make it remain open all the time. This threw off the AFR so much the car ran horribly. Simply put it back in place and the car ran great. I cannot for the life of me find any info on the location of the pop off valve. Where is it? Im having a similar problem. car wont even start and if it does it will run absolutely terribly at 500 rpm and 10 in vacuum Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 3, 2013 Share Posted February 3, 2013 Do loop... Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 3, 2013 Share Posted February 3, 2013 Ive seen the diagram^^ it doesnt help me locate the actual valve. Its pretty vauge Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 3, 2013 Share Posted February 3, 2013 Have you looked at the bottom of the intake manifold? I've never seen one but that's where I'd look. Based on the drawing. Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 3, 2013 Share Posted February 3, 2013 Ya i looked, didnt find it. And ive heard the pop off valve vent so i know its therre Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 3, 2013 Share Posted February 3, 2013 Just curious - did you look before my post or after? Wondering if I'm really that good at figuring out what a drawing is showing, and if I added any value... Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 3, 2013 Share Posted February 3, 2013 W T F?^^^ New zed, i looked before u posted that. I dont post until ive searched and tried and searched again. Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 3, 2013 Share Posted February 3, 2013 The wtf was to that 2000 word post Quote Link to comment Share on other sites More sharing options...
loy Posted February 4, 2013 Share Posted February 4, 2013 Yeah spammers post once in a while and get deleted without any notice. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted February 4, 2013 Share Posted February 4, 2013 (edited) The "Emergency Relief Valve" on the stock intake manifold is on TOP just aft of the A.A.C.. (that drawing above does NOT show stock components in their actual location! It's a representation of the ECCS system and it's component parts laid out so you can easily see function) You can't miss the "pop-off", it's sorta big and round - looks like it has a lid on top (well, it does have a lid on top...). If you keep going aft, there's the vacuum fitting for the brake booster and then the EGR... It's built to relieve pressure over ~9 pounds or so. So if your wastegate gets stuck or there's some sort of failure that would cause excessive boost, it opens and let's the air out... Under normal operation, this will never happen. If you put a manual boost controller on your turbo, set it to 10 pounds and stick your foot in it, you'll eventually hear the "pop", and rattling wheeze of the emergency relief valve. This safety valve is in addition to the internal "blow off valve" (not actually called that by Nissan) built into the manifold. You can remove and test it - it just unscrews. Note the large HEX pattern near the bottom of the device. It you're unsure, go to Home Depot, buy a 1" black (galvanized, brass) pipe plug and screw it in the emergency relief valve hole (teflon tape or a little paste on the threads of the plug - NOT on the threads of the hole (female threads) - please don't drop / get anything down IN the manifold...). In the '82 FSM, EF & EC-74 show the operation of the E.R.V. but I couldn't find a drawing that shows it's position on the manifold clearly. Edited February 4, 2013 by cgsheen Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 4, 2013 Share Posted February 4, 2013 In that case, mines been removed and blocked off, so im wondering what i heard a couple months back when i spiked at 12 psi and heard a screeching/pop noise. Cant for the life of me figure out this no start problem... Barely starts if at all. Usually just cranks. If it starts itll barely idle at 500 rpm, and 10" vacuum. Misses terribly. Grounding plugs one at a time on the strut tower they get spark. Theyre getting soaked w fuel. Compression is solid all cyls. Seems like a huge vac leak. The only thing i swapped out were afms, swpped back. Thought i destroyed the crank angle sensor so i jus wired up my optical cas in the dist today and it didnt change. Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 4, 2013 Share Posted February 4, 2013 (edited) It was worth a shot. The FSM shows it on the side and on top also. I assume, at least, that it looks kind of like the 2nd picture. Edited February 4, 2013 by NewZed Quote Link to comment Share on other sites More sharing options...
SDgoods Posted February 4, 2013 Share Posted February 4, 2013 Ya, ive ruled it out, the valve has been removed. Theres another underlying problem Quote Link to comment Share on other sites More sharing options...
Tony D Posted February 15, 2013 Share Posted February 15, 2013 (edited) You guys are mistaking SCHEMATIC DIAGRAMS meant to convey functional understanding of a system to DRAWINGS OR PHOTOS which actually show the location of the actual components. If you look in the Turbo Supplement for an 81, or the ECCS COMPONENT LOCATION DRAWING at the front of the ECCS System Section of the FSM, you will see the components circled and arrows showing EXACTLY where the things are on the actual ENGINE. One thing you learn early on with schematics in electrical circuits: wiring diagrams may bear no resemblance to what you see on a schematic, but it works just the way the schematic says it will. Same for the mechanical components. It's likely the screech and pop you heard was a surge event in the turbo. Edited February 15, 2013 by Tony D Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 15, 2013 Share Posted February 15, 2013 Nissan forgot to put the relief valve in the Component Parts drawing, or didn't think it belonged (they left the PCV valve out also), so the schematics were the next best place to look. Good engineering practice is to make any illustration as descriptive as possible. The drawing is misleading and could be improved. At least they showed it's general shape on EF-30. Quote Link to comment Share on other sites More sharing options...
Tony D Posted February 16, 2013 Share Posted February 16, 2013 (edited) The PCV is clearly defined elsewhere, and if you take a look again: there it is, emergency relief valve, the only COMPONENT not clearly identified! By looking at the other drawings defining the Emergency Blow Off Valve, you can easily see the same outline right there on the manifold, at the rear in front of the EGR, behind the A.A.C. Valve... To be fair it's a turbocharger safety component and shouldn't be on that List. The blow off valve is not really well defined either, but it's got one. But for a reference point for a guy who has no clue what he's looking at...EF30 CLEARLY shows the Emergency Relief Valve and it could have been circled with FAR better recognition than the prior examples (which were SCHEMATIC in function, not diagrammatic!) Had it been circled on EF30 (or the ECCS and EFI versions compared "what looks different between these two drawing's un identified components?") I think location confusion would have been over after that post. No? Edited February 16, 2013 by Tony D Quote Link to comment Share on other sites More sharing options...
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