motomanmike

https://www.youtube.com/watch?v=alSXDNewVQ8 This is what fuel pressure looks like. I'm not sure it should fluctuate that much. FP might be set a little high but I wanted to see what it ran like. At least I can see what it's doing now. edited to fix messed up link. Sorry about that I did it on my phone in the shop

Yeah its always something. I'm not sure what route to really go at this point. I know what 2 cylinders I've got an issue on though which helps alot I guess.

Strange thing is idle quality does change pulling the plug wires on every cylinder. Idle quality also changes on every cylinder pulling the injector plugs. So they are firing, both injectors and plugs, just not right I guess. I'm really afraid this is going to turn into many many more hours of wrench time. I'm going to try to get the fittings for a leak down test from work. Maybe try it this weekend.

Not sure whether you could or would want adopt one or not but wasn't' the stock 280zx injector cooling fan temp sensor in the heater hose with a 2 wire set up? Might be able to use an old stock one in the hose easily to turn the fan on? If not use a 280zx style thermostat housing with all the spots on it you could tap quite a few sensors in if needed.

Yes, the original wiring diagrams you are looking at are for using a the DB37 harness. You only have 1 ground, 1 switched power, and one constant power to the relay board. The relay harness gets the power it needs to feed the ECU from the relay board. Make sure you run your sensor wires and sensor returns back to the relay board in the appropriate spots. The relay board really eliminates a lot of gray area as far as the wiring goes. Good luck. I'm still fighting a misfire with my install. Not sure what it is yet but hopefully yours will fire up and run right after a little tinkering. Good luck.

You'll have to be specific and maybe post a picture so we can help you, at the very least let us know which marks on the board you are referring too. Pretty much everything with MS has a specific place to solder each lead or will tell you in the manual if polarity doesn't or does matter. The steps you are doing depend alot on what you are doing with ignition too.

you could. The injector wiring shown on the DIY site powers 2 banks of 3 injectors only. So 2 wires to 3 injector positives, 2 wires to the other 3 injector positives, That took up the entire 4 slot 12v feed.. I don't think powering the distributor would hurt in either of those 4 positive slots. Its only an LED so it doesn't draw much I would just be concerned with noise but you might be ok. Read about noise. You probably will have it at some point but maybe you'll get lucky.

Relay board gives you 4 12v pins for whatever you need. Look on the DIY write up

pulled plugs and did compression test today. All cylinders between 127-131 psi across the board. 1-2-3 plugs look good 4 is black, 5 good, 6 is black. so 4 and 6 are dark, not sure what it is. #6 was a dark oily plug but compression was better than 5 which was the nice chocolate milk colored plug. Injectors are here but I have not installed them yet. I'm waiting on a regulator and gauge and am going to. I drove it a bit today and am so annoyed with the way it runs. Its crying for more work. Still have that misfire stutter. Put new plugs in it, same response. Going to re adjust the valves and re do compression tests but probably not today.

I might turn it off. I just kind of wanted it as a fail safe in case temps got that high once it warms up here. I'll turn it off for now. If I see the temps get too high it will be a good excuse to add an intercooler I guess

well, that is a good question actually. I noticed MAT correction was coming on at points in time. I haven't researched MAT correction enough to fully understand what I should do with it. MAT temps i've never seen anything over 120. I understand it changes timing if MAT temps get too high or whatever you want to set it at but that was for me to get it to stop turning on. I could see it on a datalog originally, setting it to that i've never seen it come on now as of yet.

I just ordered a set of high impedence 400cc injectors from oside tirger. Hopefully will have them installed in the next week or two. I've searched but can't seem to find any of the voltage correction settings for MS yet but when i do i'll post up how they work out. I got them in the standard barbed style. The guy was very helpful. I'm sending my original injectors back for flow testing. He also said if I decided to go with a oring style rail later on he could change them up. He charges $7 a piece to test them on the flow bench which seems reasonable enough to me because my local napa can do them but charge 125 a set!!

As far as accel enrichment being off. 900% threshold means, the throttle position has to change 900% from its current position in order to trigger accel enrichment. With an enrichment of .01ms it does not really affect the pulse width of the injectors even if it does trigger it wouldn't really affect it. In addition typically when I feel the stumble, I see a leaner reading, if the enrichment was activating i would think i'd see the opposite. It is 100% TPS driven, however you have to really like I said floor the thing from dead idle to full throttle before it will even kick on. I'm not seeing any glitches on TPS and on data logs I never see the "active filter" display showing enrichment was triggered. My TPS is stable doesn't flutter or have any needle bouncing.

I have turned it off. I don't see the LED come on for enrichment unless i'm at a dead idle and floor it really fast. Driving it normal, even spirited I don't ever see it come one unless i go from one position in throttle to full throttle very fast and even then it doesn't spike the pulse width or anything on the data log. I had it on testing during that datalog just playing. I really was trying everything I could think of that day. The weather was decent and I played around for a good 2 hours trying various settings. EGO has always been off. Tried with accel enrich on, different settings, and off. Played with voltage correction which did have the most affect on how it felt but still never got it smooth. Its been fun. Skirkland are you using a trigger wheel, stock cas wheel or a DIY wheel to get your rpm signal? Reason I ask because you can't physically see is actual engine timing (i know you experienced issues with timing not following tunerstudio). Timing jumping around would cause what I'm seeing/feeling but i recall yours being more locked at one degree or the other right?

I was referring to taking a data log and then playing it back in megalogviewer on its VE analyze section. I should have been a more specific.

Do you mean a screen shot of VE analyze after running the analysis? EGO step size is 0 so EGO is not affecting it. Accel enrichment is sett to %900 percent threshold so I REALLY have to mash the pedal pretty fast before it will even activate. Anything else i'm missing? I guess i'm not clear on what you mean by wideband correction? I don't see anything activating when it shouldn't on the log either looking at all the small data sets in the cells at the bottom of the log viewer. CURRENT TUNE.zip

I don't have any leaks or smoke so i doubt the headgasket is bad but its possible i suppose. I'm just leaning towards fuel because of my situation. The injectors were off ebay. A full set of six, however I do not know the brand, do not know if they are matched. Just said they were for a turbo 280zx. The car, even last night when it was snowing here, fired up second crank without touching anything just turning the key so MS is right, start up and WUE is right. I did notice the car runs SMOOTH as can be during the WUE cycle, as soon as that LED goes off i hear the miss. Very strange. Not sure if its related to the drop in idle, or if its something quirky with MS or not. I will test compression again. Install new plugs and do plug readings for each cylinder. I'll let you guys know what I find. Might not be for a week or so the weather has been really crazy this week. At least the thing is back together Jackstand races are over for now.

Learned that the hard way a month or so ago. Matt, I do just want to say thank you. You guys have been really awesome in leading me in the right direction with things. The repairs to the boards etc. I've learned to diagnose and repair the injector drivers, the daughtercard tests, ignition outputs etc. I've installed a few of these things now and all have went smooth except my own car (which i'd rather have it that way) however it is a little frustrating at the same time. I'm fighting a misfire and I don't really think its megasquirt anymore. I took a datalog and video of a run recently just to see how the AFR's on the LC1 gauge looked VS the MS datalog. I'm going to change injectors to some high impedence injectors and maybe rule out a bad injector. Its pretty close. attached is the datalog when this video was taken, if you turn the sound up on the video for youtube you can hear the break up but AFR's stay within a safe range IMO but maybe i'm not seeing something. They are erratic though, not linear in any fashion. Neither is the car, it stumbles, stutters, especially out of boost. In boost I guess its blowing so much fuel it kind of masks the problem The battery voltage is up down up down up down in areas, but its only about a volt fluctuation. Playing with battery correction on the injectors changes how it acts but doesn't eliminate the issue. I tried values from .001 up to.500, in incriments of about .025 each time. I even tried .800 at one point but it ran terrible. Seems to run its best at about .450 which seems high IMO.

Man this was today? I would have rode there if I knew it was going on. That Z is CLEAN!

I've also send an email regarding a rail. Hopefully will hear back.

I installed the cap on the H1 boot . I have upped the table size now to a 16x16 and cut off my muffler so now its just a straight back exhaust. I've ran about 2 hours total of data logs and my VE analyze on hard will barely change my tune. My car runs ok, It will run through all the gears, boost and cruise but it isn't smooth at all. I still have a misfire. I'm convinced now that MS isn't my issue and am looking further into the basics because the datalogs look pretty good. On the hunt for a sender and gauge to monitor fuel pressure in the car while driving. Also going to get my injectors flow tested somewhere. They were new when I got them but that doesn't mean they are right. I had an issue with an injector driver in this swap and maybe it fried an injector who knows. Datalogs look ok, the battery voltage stutters a total of .8 volts when I get the misfire but its from 14.1-13.4 or so. The misfire is causing the AFR to fluctuate to the lean side. Thats why my AFR readings look so horrible.(heart monitor) The RPM changes pretty consistent with the stutter so I'm sure the alternators just reacting to the engine speed i think is why my battery voltage fluctuates like it does. I don't get any resets. I don't lose logs. The fluctuations of the AFR directly coorelate with the misfire. Not every bump, but when you see a full change of 1 on the afr it happened. 2 questions A regular old style coil like i'm using My understanding is they either work or they don't, there really isn't much in between? Running I think 3.0 on dwell if memory serves correct. Is there any way an injector can be bad but seem to work ok in certain areas? I thought I remember seeing a post about a guy with a bad injector. The car ran ok but had problems at certain RPM i think it was in boost, the only way he could tell it had an issue was on a scope. I've also read posts where a guy swore MS was his problem for weeks and it ended up being a bad seal on the injector letting air into the mixture past the throttle body. Some thing is wrong with this set up. It acts better in boost than under 100kpa but still stutters some in boost. Does not detonate but stutters. I have 2 MS boxes and they all act the same so It isn't MS. I've replaced most everything there is to replace before I installed the engine but something isn't playing icen and i'm really running out of ideas. I've sprayed starting fluid all over the manifold to test for vacuum leaks with no change in rpm. i've pulled the connectors off of each injector and the rpm does change. I've listened to hear them clicking with a stethoscope and they call click away so they are firing. Not sure which direction to head. I pondered air bubbles in the fuel, but i would think i'd see a leak. I've made sure the pick up feed tube is tight and all fittings are tight going to the pump just in case. New Compressed (zipped) Folder.zip

Are you running batch fire or alternating. Also are both banks settings the same if you are using two banks.

You are probably going to need machine work. "worth saving" isn't really something anyone can decide for you. If its worth it to you is what you have to figure out. Motors are fairly cheap. Your cheapest option to get rolling will be finding a decent running motor. The kits to rebuild are around 400-500 bare minimum without machine work. I know there are plenty of L series NA motors out there for much cheaper. To give you an example. The motor currently in my first Z is a $300 ebay motor and i've flogged the crap out of it for the past 5 years. It still runs strong. Whatever you end up doing, save the rods. People use the L24 rods for some builds.