motomanmike

So I get to work today and i'm plugging away ordering products for the company and my boss walks in. He said come one boys we have to move some stuff around and tosses me a key fob. I look down and its an audi emblem. Well we work on cars so i'm thinking we have to move around customers job cars. Well it was the key to his brand new Audi R8. THIS THING IS SICK!!!! So he sends my co worker with me to "keep an eye on me" he says while we move all of his toys to the new building our business is moving to across town. Well I got in, looked at him and said "i've been saving my points all these years for this day put your seatbelt on". I got acclimated with the clusters and the paddle shifters. Put the car in gear, clicked the shifter and we were off. As soon as I got onto the highway i straightened up and dumped it, hit second, hit third, looked down 109 and backed off. It hit that in a matter of seconds, no time at all. What an awesome morning at work. I am surprised at how mechanical the drivetrain feels on such a car, it makes me feel better about my clunky z driveline because that was a 200k car and it had some clunks to it with the sequential gearbox i guess. Its definetly not a car to cruise around town in, it wants to stretch and will stop on a dime!!! Amazing morning just thought i'd share. Below is a pic of the car.

I got a wideband LC1 with gauge at a swap meet from a buddy for $65 this past weekend. He had an old supra project he gave up on. All new in box what a deal! I can't wait for this set up to get here. I've prepped by removing all the old harness and pulled off anything I won't be using with megasquirt. I guess this thread is dead now. I'll be posting everything else I have issues with in the future I guess in the EMS thread. Thanks for everyones help trying to troubleshoot this stock system. I concluded the ECU was indeed bad on it by the looks of the board and decided to go with a megasquirt system from DIY autotune. Mike

Lets just say a credit card is a good thing sometimes. MSII pcb3.57, stim, harness and cables/sensors on the way soon, ordered today. I have to source a tps sensor and get a wideband. I couldn't bring myself to spend any more money on something I couldn't truely control. It will be tough to get it going from here but i'm sure but i'll get it. I 'll let you know how it goes guys. This could be a very long road ahead so it may be awhile LOL. I pulled all the old harness out and bolted up my MSA downpipe and blocked off the EGR today. Still moving forward.

It looks like corrosion to me but I guess its the inside of the diode melted out. It only appears to be on the white diodes, the rest of the board looks normal. Its all over the board like this in spots, where the white and blue diodes are. I may have hooked up something wrong initially trying to get fire and spark or would imagine some pins were crossed because there was some serious rust flakes from the case of the ECU laying on the board itself when I opened it. They probably conducted power where it shouldn't go laying across some of the pins. I havn't made a decision on what i'm going to do yet but I think this would be a problem with why it wasn't running right. Really thinking i might let it sit until I can save enough for MS. If I can find a cheap ECU under $50 or something I might try it but anything more than that i'll probably just save my money up and go for the gusto.

Would you think it has anything to do with the ECU now??? Looks like its growing some funk on the board. This car ran like this.

Did you ever get to the bottom of your issue Ryan? Just curious what you found out.

I've used the later 280zx (pretty sure its the same as the maxima) on both my 73's. Its an easy swap, just wire in 1 diode on the plug and switch a few wires. The writeup is well documented in here. 14592 is the Remy part number i've used on both. Bolts right up to the existing mounts. Makes your headlights much brighter at night. The write up says to jump some pins in the plug where the regulator would plug in but I left it plugged in with no modification on my cars and it worked fine and all my gauges still work. I've been running the one for the past 3 years and have logged about 10k miles on it. Not sure if the 73 is unique in that sense or not. I'd stay away from the 10si GM alts. The mounting has to be fabricated slightly although its not too troublesome. I've seen guys have alignment issues in addition they don't charge well at low RPM with the 1 wire set ups unless you can find a really small pulley to fit it. 1 wire alternators are also notorious for overcharging, 15-16 volts or even higher i've seen numerous times.

Really suspecting the ECU the more I think about it. Why else would one single injector plug have both wires activated with 12v when I checked the other morning and then that night it be normal with very minimal moving of the harness? I wasn't imagining things, I checked those two plugs multiple times. I'm really baffled. That night testing those wires only had 12v on one pin of the injector plug and would fire a noid light. I don't want to buy more parts trying to fix a gremlin I can't find. The reason I keep leaning toward a MS system is i would know it is a "known good system and good harness" Yes its more complex but no matter what some may think by reading my posts I'm certain i'm capable of doing it. I don't have friends that have Datsun's I can borrow parts from and try. My other 240z is a carbed car. No one where I live even knows what they are half the time. I verified just visually the firing order last night. I need to pull the plugs and rotate the motor with a wrench and get it to TDC and see where the rotor in the distributor falls. It was right during assembly originally so I wouldn't think it changed at all. I really feel its in the injector cycle somewhere because of how it will run either misting fuel or starter fluid into the intake it runs fine. I know its firing a noid light but it seems dim to me looking at it. I really appreciate everyone's input.

Nope dead on firing order I know it runs ok misting fuel into it and idled quite well before all vacuum leaks were plugged a few weeks ago testing. I'm baffled. I'll mess with it this weekend looks like this one will stretch into winter. I wanted it to be a summer project but that doesn't seem to be the case. It's kind of new to me carbed cars have never given me as much trouble as this 20 year old efi system lol. I have a Toyota truck and they don't break much so this all has been a learning experience and I haven't learned enough yet it seems.

Interesting

I didn't have much time tonight but the phenomenon is no longer present, all injector plugs only have 1 pin with 12v on each plug. All will fire a noid light. I know for a fact 2 of them had 12v on both pins this morning and I tied them together. Those were the first 2 I checked when I got home. Very odd indeed. I'll be able to do more this weekend testing I'll get the motor started up and pull plugs all over and see if I find one that has no affect on operation when pulled. I'm not replacing things just to replace them, I'm not made of money so my frustration grew even greater last night. I will test the harness Saturday and see what I find I don't know if the reman AFM is even any good it doesn't fall in range with the FSM either and I read a post last night that said known good AFM test bad by FSM tests which to me is now believeable.

CGSHEEN, are you saying both of the 2 pins on a single injector plug should have 12volts? 4 of mine have 12 volts on one side of the plug, the other 2 injector plugs have 12volts on both sides.

Yeah I think you are correct, they all have an individual positive feed and all batch fire from one common ground. What i'd like to try is to feed the 2 injectors that the plugs don't have correct readings on from another known good firing injector plug. If that is not a good thing to do maybe someone has tried it? My thinking is that if they all share a common ground I don't see why I couldn't wire the 12v feed of the one side of the injector plug, then just cut the negative plug that makes the injectors fire at the ECU and run a dedicated new wire up to the injectors and save me the trouble of cutting this whole harness open. (this is all just a theory and may be totally in left field)

I wish I had another ECU to try but i'll check the wiring. Maybe I can scoop up an ecu fairly cheap if that is my problem. I just grit my teeth every dollar I spend on this old setup thinking man i'm halfway to a MS system by now.

Thought, why couldn't I just cut one side of the pigtail wire, and share the ground signal from an injector plug i'm not having issues with.

Update, I think I found the problem or part of the problem doing some testing really quick this morning. On 2 of my front injector plugs, I have 12v on both sides of the pigtail plug. Seems my problem may be deep in the bowels of this harness somewhere, they have to be rubbing or broken at a similar spot to pass through. I hope this hasn't ruined the ECU. Whats the easiest way to find it? Just dismantle all the loom and check, or ground one end and probe around with a meter at both the other end or what? I only had about a half hour this morning before work to test but eventhough i'm bummed about it it is very encouraging that I found an big issue. Wierd thing is it will fire my cheap ebay noid light so i think the ecu will be ok.

Well its not the AFM. Installed it and it has the same symptoms. I'm missing something. I don't want to even speculate any further. I'll keep probing just don't have much time during the work week.

I think i'll just need a cap for the tube out of the manifold using the msa downpipe, i'm pretty sure the MSA unit doesn't have any other bung other than for the o2 sensor. The car will run great if you mist fuel into the intake so I know its not missing. I've also verified with just laying each plug wire on the cylinder with spark plug attached and can visually see spark. Hopefully my AFM will be here today and we can see which direction i'll be headed. Thanks for input on the EGR, I wasn't sure how much they actually affected the stability of the system. I've read they can be beneficial by lowering combustion temperatures but it seems marginal at best the advantages it would have on this set up. I may have a bad ecu, there are a lot of test in the FSM that following the flow charts end at replacing the ecu. If the AFM I get doesn't change things, and after some more testing I conclude it "may" have a bad ECU i'm not sure which route I will go. Sinking more money in a very dated setup when I could go with a nice MS2 seems like a no brainer.

CGsheen, I appreciate the thoughts. If this AFM i've ordered doesn't make the car driveable, I'm definetly going megasquirt. I've emailed and researched quite a bit with Matt Cramer at DIY, those guys are more than accomidating. NewZed, the post where you had asked if my readings were a typo, I figured that out, I have a self adjusting ohm meter and it went into kiloohm mode, hence the K ohms, i'm sure some knew what it was but I didn't, just multiply those values by 1000. Made total sense when the rebuilder here told me that. So that makes my readings for my air temperature sensor tests in my current AFM very low, its 80 degrees outside and the car thinks its hanging out with polar bears. Tomorrow I get parts, we shall see. I ordered a MSA downpipe, that way I have it installed before I go get my custom exhaust done and can do it right with as few welds as possible. I will have to block of the stock EGR valve. Eventually i'll put on this non EGR intake I have but I wanted to wait until I get it driving to do too much more to it. Will blocking off the EGR now affect the stock computer system enough to cause issue, should I hold off on putting this downpipe on and get the exhaust done using the stock set up, I have 2 good stock downpipes with the egr provision, one of them I have about a foot and half of the exhaust that bolts to the 3 bolt portion of the downpipe so either way its easier for me to get exhaust made up.

Got a reman AFM on the way. kind of surprised people still reman them. Coming from a starter alternator rebuild shop background I didn't realize people even reman them. Will be here by Friday. We shall see.

I would try to source an L28ET setup whole with harness ecu etc. I'm in the midst of my L28ET swap into a 240Z, its gotten frustrating at points especially right now but I would be so mad at the moment if I had pieced all of this together because i'd be questioning even more items. At least with a base L28ET you know its designed to run boost eventhough guys have been very successful with the NA swaps to turbo. I'm really close to driving mine it will run but i havn't had to source very many parts in my opinion, right now i'm having an issue with the AFM or something i'll know in a week or so when one gets here. New fuel pump/tank because of the age of the car, coming from carbs to FI had to upgrade the lines,pump, filters etc but otherwise its in and pretty much a plug and play, well splice and play. I've got bugs but I wouldn't have expected it any other way. There is a wealth of information out there but you seem to just want an answer to one question, to buy an NA motor which is READILY available. Or buy a turbo motor first. I think you'll spend less sourcing an L28ET and i'm pretty certain the bottom ends are a little beefier amongst other things, lower compression which from my experience is more tolerable to higher boost levels. Depends on what you want to do though. Good luck

Any of you that watched the last video I posted, does it sound like its leaning out or running rich to you?

Put a 460 in and be done. My first vehicle had a 460 v8, it was a huge F250 ext cab 2WD but was quite the sleeper. If you are set on a ford go for it. I chose an L28ET, i'm still working the bugs out 4-5 months later. It runs though so i'm almost there.

Its an 82 setup with the 4 pin plug on the distributor, doesn't necessarily mean i have the right AFM either. I sourced one though. Probably going to try but they want quite a bit used, say its a reman, i have to price them at work and see if thats in the ballpark. Its adding up quick, by the time I get done fixing all the stock stuff I probably could have bought a MS lol

Not sure if you can see that or not?