Tightmopedman9 Posted May 5, 2015 Author Report Share Posted May 5, 2015 Looking really good! I've been doing some thinking on the springrate question, and I think it wouldn't be as much of a problem, because when loading up you're softest spring, there will be a point where the total pressure absorbed by the softest spring will equal the springrate of the harder spring. At that point they will be progressively combined. At least: that's what my knowledge and imagination tells me.Your progress is motivating aswell: I'm making the partslist for my suspension revamp! I'll be keeping an eye on this thread!I'm not exactly sure what you're saying, but when using two springs stacked on top of each other the effective spring rate is K1*K2/(K1+K2). Since the total deflection is shared between the two springs the spring rate is effectively decreased. When using springs with different rates, when the softer spring binds the spring rate will equal the rate of the stiffer spring. Where did you find a kappa perfect sub? Most underrated sub out there. Mine are 10+ years old and probably getting tired so I've been looking for replacements. I've had two of them for a while. I think they still have NOS of the 10.1VQ, I see them pop up new every once in a while. Not sure if it's just me, but the images aren't working on Aaron's post on 4/28.Hmm... Still looks like it's working to me. Quote Link to comment Share on other sites More sharing options...
Smiles855R Posted May 6, 2015 Report Share Posted May 6, 2015 Must of just been my computer at work, it's fine at home Quote Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted June 13, 2015 Author Report Share Posted June 13, 2015 (edited) Please excuse the poor camera quality photos, but consider this more of a teaser. I wanted to wait until I had at least started on road tuning before posting anything, but I am in need of some assistance. I redid the majority of the 'A' engine and trans harness; I integrated COP, EV14 connectors, did away with the PNP wiring and converted to the manual starter wiring etc. I put the battery in the back as well. Now, the car starts, but dies after idling for only a few seconds. Doesn't matter if I rev it up or just let it hang, it always seems to die within a few seconds, and this happens consistently, seemingly unrelated to anything I change. Things I've checked: Fuel pressure (pressure stays at 43psi while running and drops slowly after dieing) Fuel relay Voltage at coils and injectors while running (voltage stays constant while running and after dieing) Tune (I'm using 1000cc injectors and a 3.75" ID MAF) Sensors (from what I can see every sensor appears to be functioning properly) I've been troubleshooting for the past 6 hours and everything I check seems to be fine. Edited April 30, 2017 by Tightmopedman9 1 Quote Link to comment Share on other sites More sharing options...
gdog Posted June 13, 2015 Report Share Posted June 13, 2015 those photos are one hell of a tease..!how long is a few seconds? Long enough to get manifold vac reading (i.e. huge vac leak maybe?)You're sure you have fuel pressure when the engine dies? It shouldn't drop dramatically even after dieing; should take tens of minutes before you see the fuel pressure bleed off. It it's bleeding down in seconds then ck pressure regulator, for a leaky injector, weepy fuel pump ck valve, etc.Ck for spark? Got an inductive pickup timing light? Clip it onto one of the plugs and see if your fire's going out causing the engine to die..Stupid stuff like compression?injectors firing? IIRC if you lose spark, then the ecm will stop firing the injectors shortly after.. Quote Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted June 13, 2015 Author Report Share Posted June 13, 2015 how long is a few seconds? Long enough to get manifold vac reading (i.e. huge vac leak maybe?)Seems to be a consistent 3-4 seconds. Vacuum is around 12.6 inHg, which isn't great, but this is on a cold engine, just barely at idle speed. I only have two charge pipes and I've double checked all connections to make sure they're tight. Running with the MAF unplugged makes no difference. You're sure you have fuel pressure when the engine dies? It shouldn't drop dramatically even after dieing; should take tens of minutes before you see the fuel pressure bleed off. It it's bleeding down in seconds then ck pressure regulator, for a leaky injector, weepy fuel pump ck valve, etc.I have an Aeromotive 13129 adjustable FPR with a gauge mounted in the bay and the fuel pressure remains at 43psi before starting and after dieing. It used to hold 20psi overnight, but the leakdown is much faster now. I'm not sure what could have changed there, I haven't touched anything in the tank since I converted fuel lines.Ck for spark? Got an inductive pickup timing light? Clip it onto one of the plugs and see if your fire's going out causing the engine to die..I converted to COP, so a pickup light won't do me any good here. Spark was tested on 3 cylinders and was good, I checked continuity at the signal lines and power/ground, so I didn't feel the need to check the others.Stupid stuff like compression?Doubt it, since the car idles just fine until it dies.injectors firing? IIRC if you lose spark, then the ecm will stop firing the injectors shortly after..Haven't checked the injectors, but since the car idles fine I doubt they would be the problem. I think it may be a voltage problem, maybe the wiring for the COP is being cut or something. I'll investigate this in the morning. Quote Link to comment Share on other sites More sharing options...
Ol' Dirty Noodle Posted June 13, 2015 Report Share Posted June 13, 2015 CPS and flywheel are the right pair? Quote Link to comment Share on other sites More sharing options...
mattwebb502 Posted June 13, 2015 Report Share Posted June 13, 2015 (edited) I think I'd look closely at that regulator and all related plumbingpump/feed/return line mismatches or obstructions?defective unit dumping raw gas out the vac/boost port?How exactly is the gauge plumbed in the circuit? My preference would be to get a reading directly at the rail itself.Edit:Stupid question, but there's no chance of an exhaust obstruction? Backed up exhaust gasses have done the exact same to me in the past.no forgotten paper towels in the exhaust ports, etc? Far fetched, I know..... Edited June 13, 2015 by mattwebb502 Quote Link to comment Share on other sites More sharing options...
ErikS Posted June 13, 2015 Report Share Posted June 13, 2015 Are you sure all your grounds are right? Starts, idles, dies could be insufficient voltage to the fuel pump relay or ignition. Just a thought. Quote Link to comment Share on other sites More sharing options...
BlackT5 Posted June 13, 2015 Report Share Posted June 13, 2015 I'm wondering about the fuel too. Ideally, it goes pump to filter to rail, then out of the rail to the regulator and then back to the tank. Quote Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted June 13, 2015 Author Report Share Posted June 13, 2015 CPS and flywheel are the right pair?Same pair as what this engine has ran on before. A mis-match leads to a cam/crank phase angle error which wouldn't allow the engine to start, and would show up under an error-bit diagnostic test.I think I'd look closely at that regulator and all related plumbingpump/feed/return line mismatches or obstructions?defective unit dumping raw gas out the vac/boost port?How exactly is the gauge plumbed in the circuit? My preference would be to get a reading directly at the rail itself.Edit:Stupid question, but there's no chance of an exhaust obstruction? Backed up exhaust gasses have done the exact same to me in the past.no forgotten paper towels in the exhaust ports, etc? Far fetched, I know.....The fuel gauge sits directly on the regulator and therefore measures the feed pressure, and rail pressure. Measuring at the rail would give me the same pressure, just 12" away. I can't imagine that they could differ that much.Vacuum port is dry from the regulator.Right now I'm running only on the downpipe, and I can assure you (as well as my neighbors) that there is no exhaust restriction. I'm not the biggest fan of paper towels, so nothing like that.Are you sure all your grounds are right? Starts, idles, dies could be insufficient voltage to the fuel pump relay or ignition. Just a thought.Grounds are the same as stock, I actually went and added a new head ground from the main engine ground location in the bay for justin and had the same problem.I'm wondering about the fuel too. Ideally, it goes pump to filter to rail, then out of the rail to the regulator and then back to the tank.I'm not sure how else it would be done? This is the way I have it set up and monitoring fuel pressure it remains constant until a few seconds after the engine dies, at which point it starts to leak down. I removed the idiot oil light and replaced it with a oil pressure sender. I'm wondering if there is some sort of no oil pressure shutoff, I've never heard about such a thing on a P80, but it's something I'm investigating right now. Quote Link to comment Share on other sites More sharing options...
Ol' Dirty Noodle Posted June 13, 2015 Report Share Posted June 13, 2015 (edited) I'm not the biggest fan of paper towels, so nothing like that.A. L O Fucking L I removed the idiot oil light and replaced it with a oil pressure sender. I'm wondering if there is some sort of no oil pressure shutoff, I've never heard about such a thing on a P80, but it's something I'm investigating right now.B. If that were the case Kevin would still have a super low mileage motor in his 850 Edited June 13, 2015 by Ol' Dirty Noodle Quote Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted June 13, 2015 Author Report Share Posted June 13, 2015 Ha, yeah I traced the wiring for the oil pressure light, again, and came to the same conclusion as last time. It just runs straight to the cluster, and when grounded turns on the oil light. I originally cut and saved the wiring so I could tie it back into the ECU and have a secondary warning light. I've found that the coils for cylinder #1 and #3 are not firing. I've tried swapping coils, plugs and checking the wiring. The coils are getting good power, and the signal lines have continuity to the correct pins on the ECU. Just in case there was a software issue, I changed a logged RAM parameter to RAM_21 and found that the firing cylinder bit is cycling correctly. I guess the only thing to check now is the actual ECU SMD components related to the COP, but I'm not sure how they could just fail randomly. Quote Link to comment Share on other sites More sharing options...
mattwebb502 Posted June 13, 2015 Report Share Posted June 13, 2015 actual ECU SMD components related to the COP, but I'm not sure how they could just fail randomly. Failed clamp diodes in the coil packs allwoing inductive kick to damage the ecu drivers? I would think the coil packs (and ecu) would be pretty well engineered to safeguard against this, though.curious to see what you find here. Sure sounds like you're closing in on it. Yeah, figured the exhaust thing was a long shot but worth the mention Mine was a dirt filled tailpipe due to a backwards spin into a ditch. Would run for 5 seconds then quit, but it was pretty obvious. Quote Link to comment Share on other sites More sharing options...
Tightmopedman9 Posted June 13, 2015 Author Report Share Posted June 13, 2015 I've been able to get the car to idle now, but only on 3 cylinders. With the COP harness I integrated into the stock loom, I don't get spark on #1 or #3. Switching to another COP harness I get spark on all cylinders when testing, but the engine still runs rough, unplugging #4 and #5 injectors does nothing and the spark plugs are covered in gas.I tried a combination of the two harnesses and that didn't work. Quote Link to comment Share on other sites More sharing options...
mattwebb502 Posted June 14, 2015 Report Share Posted June 14, 2015 Soubds like light at the end of the tunnel to me! Possible that 1 and 3 got mixed up with something else in the harness? Doubtful. Or something is funky with the connector(s) you added? I know you said the leads passed a simple resistance test, but as you know under in-circuit load can yield very different results. Scope would be useful here. Aside from fuel fouled plugs, bore wash and loss of compression in 1 and 3?Sounds like you need to use that external harness and dry out 1 and 3. Add a cc or so of oil to each and crank with fuel/spark (ecu) fuse removed ... then get that oh yeah! running! Good luck. Quote Link to comment Share on other sites More sharing options...
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