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So the Z didn't make it to the drive.


Might have been a blessing in disguise. We had very long runs at fairly high load, some very tricky corners, and the coup de grace a 2-3 hour traffic jam on the way home. I was very happy for the automatic transmission, air conditioning, and firm brake pedal of my daily. I did miss the passing power of the datsun.




I figure I try to help trouble shoot people all the time, so I should try and trouble shoot my own problem the same way.


First off the background, TL;DR below.


I started the day by swapping my BKR7E spark plugs to BKR7EIX iridium spark plugs in hopes that it might help with an intermittent miss I could hear. Also tightened the fuel rail which was loose, reoriented the coil packs, electrical taped some wire bundles all things to clean things up.


When I tried to start the car I realized I ended up killing the battery, it was reading a measly 3.2 volts. While installing my tablet dash I must have hit the light switch and not noticed it being on. So that was an easy fix, I threw it on a charger for an hour or so and it was charged up enough to start, car started and voltage was reading 15 volts.


I got everything as buttoned up as I thought I would and pulled it out for a pre-wash drive to work out some kinks.. Car was running in paramters so I let the car warm up and was checking over little things like sealing up the shock tower holes and such when the car started running rough and stumbling.


I peaked my head in and looked at my new dash to see it running and AFR of 19-20 and stumbling. I hurriedly reached in and shut the car off. 


Car wasn't going to make it until I got this sorted so I decided to put it back inside where I could work on it only to find that the key did nothing. Turning it to ignition on didn't kick on the gauges, megasquirt, lights or anything. Turning the key to crank would not even actuate the starter solenoid, no click.


Thinking that was odd I spent the next hour and a half pushing the car near an outlet to try and charge up the battery again.


Turns out battery was still holding a charge at 12 volts, although it had dropped from 50% down to 28% according to my charger


Finding it odd that nothing at all turned on even with 12 volts, I ran a wire straight from the battery to the ignition signal wire. ECU, gauges, and fuel pump all kicked on. I tried starting again and nothing, so I unplugged the starter signal wire and tapped that against the battery and the car started right up. It was still running rough very high AFR's although they would drop if you revved them down to about 16-18 (should be below 14), some numbers I was able to grab was that the fuel pump was still generating about 30psi of fuel pressure, voltage was only reading 13.8 volts with the engine running. 




Killed battery by leaving lights on

Installed new spark plugs, taped up wire bundles, tightened fuel rail

Charged battery for 1-2 hours

Car started and ran within parameters, generated 15 volts

After a few minutes car started leaning out 19-20 afr, 16-17 when reving engine

Shut car off, tried to restart and ignition switch no longer worked (no lights, no starter)

Battery voltage was still at 12 volts

Hot wired car

Car started, ran very lean like before




So couple things come to mind:


Discharged batteries will cause weird problems, fault is in bad battery (battery is quite old, it was put in with my 7m which was at least 3-4 years ago)


Could be the alternator going bad, it was a replacement alternator that came with the motor, but I never had it tested, looked shiny and maintained 14+ volts. Faulty alternator would explain the discharging voltage and why the car started to stumble later rather then on start


Could be incorrect alternator wiring, there are only 3 wires, one is obvious, the other two can be confusing, thought was if I had it wrong I would switch it, but it seemed like I got it right the first time, can go into more detail later.


Bad ignition switch would explain why the key is not doing anything


Could have damaged or pulled something while manipulating the dash trying to pull the gauges out.


Could be the tune in megasquirt not liking the voltage differential and correcting itself to an incorrect scalar (would explain why the AFR's do drop means that it is adding fuel)


Or could be a combo of several things


Next post will delve into what I find out, what tests I run etc. Thoughts very much appreciated.

Edited by seattlejester
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If I had to guess I would say that is a diagonal brace between the strut tower and front sway bar mounting point. I fabricated something similar on my project car.

Goodness I love this forum, you really can find everything.   Quote from this thread:   Pretty sure that is what happened.    I measured what I did and found that I wa

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Pulled the battery, which barely barely comes out without me having to remove my strut brace.


Interesting fact, battery fits some later model kias, but the first hit was for an AMC pacer. Good enough to turn over a 4.2L engine then good enough for a 3L :D


Then I pulled the alternator which is a massive pain. You have to pull the turbo intake filter and intake pipe, then undo the bolts, undo the wiring, then squish the lower radiator hose flat to give it enough room to pull out and clear the water pump. Definitely a tight fit.



Also turns out like my water pump, the alternator was for the VVTI 2jz difference being the oval plug vs the round plug and the 80 amps vs the 100 amps of the earlier unit. Another lesson in finding out what you really have.


The guy at the local parts store is a Z guy, and he helped me figure out some things. He took me into the back so I could watch to boot.


He threw the alternator on the tester. It passed all 3 conditions. Just to make sure he ran it again. Second pass with flying colors.


So it seems the alternator is happy enough.


Next he threw the battery on the charger prior to testing.


He sent me this picture as I stepped out to grab a bite to eat.


Battery had a bad cell. At first that was a bit confusing as for sure I thought it would be the alternator, but if the battery is failing in its duty as a capacitor of sorts the additional strain from say the electric fans would deplete or strain more then the alternator can supply at idle  at a given notice, causing problems. New battery on order. Should pick it up today. 

Edited by seattlejester
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Don't really want to post this because it is another me being stupid thing...but to keep with my initial point.


I checked my alternator wiring. That was kosher.

Lamp = on the datsun is black with a white stripe = 7mgte Yellow with green stripe = 2jz Blue with red stripe (far left when looking at the plug with the wires going away from you)

Ignition = is a separate wire on the datsun, I used the wire that goes to the coil = 7mgte Black with yellow stripe = 2jz red with blue stripe (center when looking at the plug with wires going away from you)

Signal = datsun is yellow = 7mgte white = 2jz white with a stripe (far right when looking at the plug with the wires going away from you)


Then I picked up the new battery and installed it.


I must say having a volt meter display  in the car is great for little trouble shoots. Started the car up at 11.9 volts and it slowly drained to 11.8 volts then to 11.7 volts.


Checked that the alternator pulley was moving. Shut off the car.


Thought for a little bit and thought "alternator tested good, but battery is not charging...what is going on?"


Then I spotted a fuse holder going from the alternator to the battery.


Popped it open and




For f*cks sake...Blown fuse = no alternator charge = megasquirt freaking out.


When I wired the alternator I thought that the most it would ever have to deal with was the electric fans kicking on. I basically used the stock wiring thickness. Really you should build your car with some thought of the future. I would go back and kick myself in the balls for how many times I made that decision not to size up. In the future I'm sure I would want to kick my current self in the balls. Probably a never ending cycle.


That was also before I converted to a fuel injected, individual coil pack driven motor with an EFI pump. Honestly I'm surprised this guy survived for how long it did. My best guess is when the battery went flat and with the bad cell, trying to charge it up caused the alternator to output max amps for a sustained time and blow the fuse.


On an unrelated note managed to snap a picture of the tablet holder contraption.


Edited by seattlejester
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Small update:


Parts store did not have maxi fuse holders so I ordered one online.


Bought some 6 AWG wire. Getting the ends on was very difficult, I ended up partially crimping then soldering the ends closed.


Replaced the power wire off the alternator, this lead to a white wire in the datsun harness. I unconnected that end from the battery as well.


With the new alternator wire the engine runs very happy if I hot wire it. Started up and immediately was running 14AFR at idle. Battery was also being charged going up to 14.3 and slowly climbing up.


Wired the ignition wires back to take signal from the switch and no dice. No lights turning on no ignition signal.


Two things to note, the horn does not sound either. Additionally I did remove all the bulbs to prevent a potential fire hazard as well as the speedometer. I don't see any wires running through them, anyone catch something wrong off the bat there?


The ignition test seems to work. Both switches seem to run correct pathways when cycling through. 


Also correct me if I am wrong, but the white wire with the red stripe should be full power to the car correct? It should be hot all the time no? Does the white wire in the engine bay turn into the white/red stripe? I'm going to have to stare at wiring diagrams for a bit.

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Goodness that is quite the quantity.


Hmm well I didn't get a reading at the ignition switch. Means there is a break between that and the battery.


I am regretting not doing a full rewire. At the same time, the more I put it off the more I will learn and be able to apply lessons learned. I could probably tease out a few lbs of wires while leaving spots to tap for future projects. The things I would do if I had time and space.

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I'll have to keep an eye out. I didn't see any good looking lots. The most promising one was like 100ft of each of 6 colors for $250.


Well good news is everything works now.


Can someone confirm if there is supposed to be a fusible link type deal in the 240z engine bay? I've changed so many things I'm not sure what is supposed to be there and what I added. Looking up diagrams as I am posting.


So as far as I can tell this is what I did/what happened.


Way back when, I shorted the fusible link when I ground the white wire thinking it was a ground. That fusible link connected to the chassis harness to the engine bay and sits somewhere along the passenger side rail. I replaced that length with an inline fuse adapter. 


When I drained my battery, in my haste I did not let it charge fully. Doing so I must have shorted a cell. This caused the sensing circuit in the alternator to think I was not making anywhere near enough voltage so it dumped the available amps into the system. This in turn blew my inline fuse for the main power and somewhere along the lines the connection between the alternator and the battery.


Replacing the inline fuse has restored all my ignition switch capabilities by powering the cabin.


My new 6 AWG wire with the 80amp maxi fuse I am guessing is bypassing the alternator to battery connection which must have shorted an inline fuse I hid somewhere or burned up the fusible link.



According to this nicely colored image5861385867_8a569761e0_b.jpg

All credit goes to saridout1985


White wire starts from starter solenoid power which is in turn fed by a thick wire from the battery. White wire which is fused with a fusible link goes into the cabin to the ammeter. From the ammeter this connects to the white wire with red stripes. This W/R wire goes to the fuse box. From the fuse box W/R goes directly to the alternator. There is another white wire being fed from the voltage regulator, is that just a wire to signal the voltage regulator?


That would make a world of sense, that would mean as the amps traveled from the alternator through W/R it traveled along W then blew the fuse before it could get to the battery junction and onto the battery.


The fact that the car was not charging makes sense as there is a break from in the circuit. The question then comes to if there is harm in what I did with feeding the battery straight from the alternator. The alternator is internally regulated so it shouldn't output more than the signal wire will allow. The confusing part is what the external voltage wiring delete actually does.


Edit 2:


So looks like there is supposed to be another fuse on the alternator to fuse box circuit. My new fused 6 AWG wire from the alternator to the battery must be bypassing this wire and the either hidden burnt out fuse or burned out fusible link. 


Given that this is supposed to go to the fuse box instead of the battery that makes me a bit worried that the way I have done it now I am running all the power through the white wire. The only thing I'm using is the brake lights and the horns since my headlights are on relays. So it might be ok. 


I will have to go back and find out if the alternator wire is indeed the one that goes to the fuse box. I imagine I will be able to take that off completely and the car will still run confirming my pathway, and running a continuity test will reveal there is a break in that wire from the alternator to the fuse box.


I definitely would have torn the wiring harness apart, but with the turbo and exhaust it makes things difficult. Taking the turbo off wouldn't be too bad if it wasn't for the drain which was an extremely tight fit. 

Edited by seattlejester
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  • 2 weeks later...

Went to formula D on fairly short notice. Very cool.


Saw the ACT guys there and chatted with one of the reps. Not sure if he was just caught on the spot, but I asked if they had any twin disks for the 2jz/R154 in the works and he said they were working on it and hoped to have something in 2018. Would be very cool to have another option especially a midrange option like ACT is known for about the 5-700hp mark.


One of the european S15s I believe this was James Deane's.


Also nice to check to see what setups people were running. Like this guy seemed to be the only guy running a pre turbo inlet to the catch can, unless the other cars were running an exhaust driven vacuum setup. Lots of EFR turbos and such as well. Very cool to see cars that I had read about in person. There was some fantastic driving.



Also cool to see the drivers interacting. Castro went almost immediately from his car to Forsberg to talk about their competition with 2 OMT's. Tuerck actually was sitting in the stands waiting for his turn. Zetsaz even got a tire fill kit handed directly to him by Tuerck in a giveaway.


The ferrari powered FT86 was there as well. If I wasn't mistaken the trigger wheel looked very similar to a DIY wheel lol.


Also saw that in the parking lot. Going to call him out if he's local. That all thread post is about 3mm or less from that power stud. I really wanted to jam a dollar bill or something in there because given that the all thread is also touching the body if that battery shifts or the all thread bends he is going to weld that battery straight to the car.


Yea not really sure what is going on anymore. If I am reading the circuit correctly....


fused white/red wire from alternator goes to fuse box

a separate white/red wire comes off of the fuse box goes to ignition/steering column and the ammeter

from ammeter the wire turns white

white wire is fused and goes to the starter junction where the battery is fed.


So I should find the white/red wire on the fuse box should have a break with the alternator. I think it was showing continuity. Going to have to recheck or at least make sure I isolate it  so it isn't being continuous through another route.


Right now I am essentially bypassing all the  first part and directly topping off the battery with my new wire. The battery in turn is supplying the fuse box. Overall not a big problem as the headlights are on their own circuit and I am not running most things in the car, but this does seem to be the wrong way to do this.


I'll have to revisit that when my head is clear.


Decided to address a bit of the heat issue. The turbo itself was getting quite warm. 


(Excuse the poor wire job, I couldn't quite commit to cutting it short quite yet)

Given the wires sit on the frame rail I thought I should address the heat. I ordered a turbo blanket for a T3 turbo from Thermal Zero. The T4 blanket fits like huge S400 turbos so very much overkill for my S200. I spent about 3 times the going rate for a generic blanket as I wanted to avoid fiberglass and cheap stitching. Turns out this guy is fiberglass as well. I suppose not too much out there that can affordably insulate high heat. Can't say much for the stitching, but we will see how long it lasts. I have heard at least the warranty is excellent which is far better then what I hear about the generic ones. Also found the oil feed was working its way loose. 1/4 turn after hand tight definitely felt light and was. Put a piece of the reflective tape wrap so I can keep an eye on it to catch it rotating again.





Also found the elbow off the turbo was quite hot. I was honestly surprised the silicone hadn't started to come apart. It has a bit of an air gap from the manifold, but still enough radiation is getting it quite warm. Since it defeats the purpose of sizing my turbo to make sure it does not heat the air by maintaining peak efficiency by immediately cooking the air after it gets compress I figured something had to be done. Clocking the turbo isn't really an option, and it will be a while hopefully before I have to remove the turbo assembly at which point I will have an aluminum 90 welded on, I decided to get a bit of reflective wrap to deflect some of the excess heat. 


So quite a few things addressed. 




Plan is to go for a fairly long drive, break in the clutch, then change the oil. If I don't have any issues I can start playing around with getting more then 80% throttle and boost levels.

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FD was sweet! I'm gonna have that tire kit in my Datsun when I'm back home. Will be handy since I don't have a spare with that. Still blown away by the wacky battery tie down that guy had. Most people at least make it run front to back. Also had those wacky square fender mirrors... bizarre choices being made all around. 

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  • 3 weeks later...

Went on the first long drive to a cars and coffee last weekend.




It was really great to finally be at a meet in my fun car again. It was a fun conversation starter as well. Popping the hood occured several times.

The Mustang parked behind me and the owner was a really cool guy, I had seen his featured video on egarage, and he was just a pleasure to talk to. We compared our swaps, talked about people disapproving of the swap, kindred spirit right there.


Mechanically the car didn't miss a beat, the temperature didn't go above 185, oil pressure stayed consistent when warmed up, and engine cruised without problem.


A couple things did pop up of course. I think I lowered the boost to keep myself from glazing the clutch, so overboost was very apparent and intrusive. I imagine with a passenger in the car the increased load also made it kick in more readily. The rotating noise I was concerned about actually turned out to be the driver door just rattling. It seems it isn't quite tight against the car as if I put my hand on it and pull inward it goes away. The rattling noise in the rear was the hatch. The adjustment on the aerocatch seems to be a bit off so the hatch vibrates at highway speed. Putting a microfiber towel to space the hatch up took care of that for the moment.


(Fairlady took this pic, I think it is awesome)

After the meet I decided that instead of a planned cruise we should head up to Stu's Self Service Garage for some lift time. With both of us in the car it was rubbing the fender the rear on dips even with the dampers maxed out.


Ended up going up about 3/4 of an inch. That leaves about 4 inches of height adjustment. I was thinking that that is still insane, but in retrospect if I had flares I would totally drop the car about an inch from where it was.


Goodness I do like how the rear arms turned out. They were actually still covered in oil from when the 7mgte spewed its guts.


It was a really good day. The clean underside does remind me that I should make the rest of the car more presentable as well. I have some aesthetic things planned for the near future. I'm even contemplating modifying the roll bar to give the driver seat a couple more inches of legroom.

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Looks sweet! I love the Mustang. "Abomination" written on the valve cover is great haha. American muscle fanatics will hate on it, but everyone forgets that they originally came with an inline six. Let me know when the next cruise you do is. I'd love to come down in the infiniti.

Edited by Zetsaz
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  • 2 weeks later...
  • 2 weeks later...

For sure, I mean any guy that wants to throw a japanese motor into an american icon is ok in my book :D

I have just been trying to enjoy the car in the limited nice weather we have over here.

Zestsaz stopped by and we grabbed a few pics and went for a little drive around the block.






Pretty funny, his daily G37 absolutely dwarfs the Z.


Grabbed some food at the local eatery closeby.

Met up with fairlady, we have been kind of hanging out a bit more, he has a nice work space that he has been very generous with, and I've been saving random parts here and there, kind of a perfect situation. Unfortunately just as he started making his car awesome with a brake refurbish, new seats, lowered, bumper removed, and rims (generously lent by yours truly :)), it was stolen.


 If anyone finds a set of 15x7 konig rewinds with the center ground down to look more like watanabe's let me know! If you see the whole car, even better! L28ET swapped 280z.

Anyways, we made a day of it, taught him the basics of welding. For his future car


Ground it down a little bit, then threw on some clear coat.



Sits a bit crooked, but it has adjustment.

Went to a place called the Shop that recently opened.




They call it a premier car club, you can store cars and work on them or have them worked on. Honestly if I didn't have my own tools it might be something I would look into.

Met up with some local car guys from opposite lock.


First time actually taking the car on some twisties.

The suspension was marvelous, the car was nimble. The only problems really were the brakes feeling inadequate, the noise, and the tune running a bit lean on tip in.

The C63 AMG is also really quite fast. Not sure how we would have determined that *cough*, but decidedly I believe it would out perform me in say such an environment as from a small roll. May have to start playing with the boost settings :D.

Finally also spent some time on some aesthetics. Honestly my car is pretty standard, it was shaved a bit by the previous owner, which I finished up, but take away the gold wheels and front lip and it is pretty stock.

Decided to diverge from that a bit. There really is a fine line here, not sure how well I am walking it, but nothing is really permanent.

First off are what I am calling panda eyes.


I've seen it done before so I can't take credit here.


Then headlight covers, also pretty standard.


My first attempt. In my mind I was hoping for the best of both, but it is a bit more see thru than I wanted.


So some solid vinyl


A bit more to my liking. It stems from me noticing a natural line the headlight covers reveal. In certain angles the car almost looks angry. I decided to make it a bit more pornounced.

The light output was pretty bad to start, even with HID's in a projected lens.


So I swapped to the LED lights another forum member had pretty good success with. These fit with no modification other than making the hole a bit bigger in the back to account for the bigger plug, which mine already were from the moving HID setup I had ages ago.


Did some wiring and wrapping for the adapters. Hoping to put them in and test today. Honestly not the biggest deal. I can pull the headlight covers if it turns out the light output is cut drastically, not that I drive around very often at night.

All my clear lenses arrived as well. So I finished wiring the side markers, and now all I have left are the front turn signals which I need to repair the housings and clean before installing all new hardware.

Let me know what you guys think. Everything is reversible other than the headlights, which I think I will keep regardless. Vinyl wrap also seems to be pretty doable. Some of the curves can be a real pain, but with the new stuff with heat activation you have a lot of room to readjust. Might be going down that route honestly.


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The painted sugar scoops with headlight covers look good, but I don't like the vinyl. Partly because it's stark white and doesn't really match your paint, but personally I just don't really like the idea. Takes away from the purpose of blacking out the sugar scoops IMO.

Let us know how you like the LED headlights. As much as I like the idea of LED headlights, I don't know if I can get past the look of them. Are those the Trucklite(?) brand lights?

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Some nice progress! I'm assuming you got the painted covers idea from the Mr. Vengeance Z? I remember you mentioning that when we were talking cheap paint jobs that didn't look terrible haha.


That shop looks neat! If they ever have another meetup of some kind let me know. I'd love to go check out their stuff. It might be a nice way to get my Z up here faster if I have a safe place to put it. Currently I just have too many sitting at my place here. I have the G37, the hardbody, and my 240 parts car. Need to finish stripping out the parts car so I can clear out some space. 

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17 hours ago, rturbo 930 said:

The painted sugar scoops with headlight covers look good, but I don't like the vinyl. Partly because it's stark white and doesn't really match your paint, but personally I just don't really like the idea. Takes away from the purpose of blacking out the sugar scoops IMO.

Let us know how you like the LED headlights. As much as I like the idea of LED headlights, I don't know if I can get past the look of them. Are those the Trucklite(?) brand lights?

Fair enough, I'm still on the fence, I think I am going to pursue the idea to completion before I really take stock, I feel like there is something there that might be kind of neat.

I don't really recall the brand, I followed the link and just ordered it off of amazon from the poster on here since I wanted the option to return it if necessary. Wired it up last night, and goodness these are great. They throw a really good beam, so lighting I think is not going to be a problem now. The vinyl get's blown out on camera, but the car does look quite angry which is what I was going for. 

1 hour ago, Zetsaz said:

Some nice progress! I'm assuming you got the painted covers idea from the Mr. Vengeance Z? I remember you mentioning that when we were talking cheap paint jobs that didn't look terrible haha.


That shop looks neat! If they ever have another meetup of some kind let me know. I'd love to go check out their stuff. It might be a nice way to get my Z up here faster if I have a safe place to put it. Currently I just have too many sitting at my place here. I have the G37, the hardbody, and my 240 parts car. Need to finish stripping out the parts car so I can clear out some space. 

Yea that is the guy, I couldn't remember his name. I think he called them zombie eyes. When you look at them from the front on a white car though to me they look like panda eyes :D

They have a standing meet on Saturdays. I mean the storage isn't cheap, I think it is $200 a month on top of a membership fee and initiation fee. 

Assembling the clear turn signals, then I'll update with a picture. The clears really clean up the front end in my book.

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