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Wiring:
I'll go wire by wire for reference. Note that i have not run the car yet, i will update this later.
These are all the splices or taps that i've made.
Car is a '99 Miata using the Kmiata swap harness
Black wire (small gauge): spliced into Green/orange wire in the black cluster plug
Blue wire (small gauge): Spliced into red/green wire in the Green ecu plug
yellow wire (MIL): white/light blue wire in black cluster plug
brown wire: yellow/red wire in small white cluster plug
silver wire: VSS Signal. optional. connected to vss wire from hondata.
OE coolant sensor signal wire: spliced into violet/white wire in blue plug
black wire (starter, large gauge): black/red wire at clutch interlock switch
orange wire: black/white in blue plug
red wire: blue/red in green plug
blue wire (large gauge): Green/red wire in the green plug (12v source)
green fuel pump wire: red/blue from stock fuel pump relay (check continuity between fuel pump to be sure)
pink wire: black/yellow wire at the fuse block, tap into 15amp meter fuse
I did not hook up the o2 sensor, as i'm not running a denso sensor as recommended. I will be using the AEM UEGO sensor and wiring it directly to the ecu.
I think that's it. here are some pics of the relevant connections.
Tonight was eventful!
PPF bolts weren't happy. Can't get the front one in. I'll mess with it on a lift at a later time. It's at the point the exhaust can be fabricated. That was the goal. Good night
Engine is in the car, Exhaust is in progress, and a few loose ends got tied up.
Exhaust pics:
Had a really tight clearance from the body to the adapter plate on the passenger side. Clearanced that with a dremel:
And the shifter was installed:
No pics, but i worked on the charge harness. Got that sorted out, then threw the engine harness on there, put oil in it, and attempted to start it.
Engine cranks just fine, but no fuel. Kmanager doesn't appear to be communicating, though i was able to pull the basemap from it. This was father's day, so i didn't get to spend much time on it. I need to clean up the wiring, bleed the clutch, build an intake, and figure out the fueling issue.
Last update i mentioned that i had the motor spinning over, but i hadn't mentioned what happened later. Wall of text incoming!
It's Sunday, Father's day to boot, and i thought i could spend 2hr in the garage to see if this thing would make smoke. I was able to get the starter to turn, but had no fuel. I had my son crank it while i messed around under hood, to no avail.
I went from that to the laptop, trying to communicate to the ECU. He was in the drivers seat acting like Mario Andretti. Lol, have fun kid
We had family obligations, so i couldn't mess with it until..
Sunday evening.
Now the car won't turn over. Just clicks. I put a wrench on the crank, won't turn. Only goes about 10* backwards too. Now i have done it, the motor is locked up! But how? I never could give it any real rpm ... It was a long day, i called it and went inside.
Monday morning: I woke up and laid in bed thinking about the car. After about ten minutes, the epiphany hit....i haven't bled the clutch! It's probably down there, in gear, no clutch, with the handbrake on. Sure enough, that was it! Feeling pretty good, it cranks again!!!
Monday afternoon:
My Honda buddy David came by, and did some diagnosing. Thought we had a power issue, traced all 4 12v connections, which were fine.
ECU still won't light up. Started tracing grounds, and found that the hole in the valve cover i used to ground the harness is not acceptable. Moved it to a valve cover mounting bolt instead, and it has power!
Went to start it, low and behold she fired up! For about 3 seconds. She died in a clang, wouldn't restart.
Cranking it sounds like no compression. Fck. Now I've really killed it.
Pull the VC, check cam timing. Looks ok, so does the crank pulley. Need to pull timing cover to check the rest. Got the cover off, the marks might be off a tooth, but are close enough to run... David asks for a 17 to rotate the engine with the intake cam, and the bolt gives him no resistance...
At this point I'm positive that I've screwed something up, either the VTC gear, sheared the pin off of the cam, something...
But he is a trooper, so we soldier on. Pulled the gear off, and find that the gear walked off enough to disengage from the cam dowel pin. Probably bent valves. But, we are here, so let's just assemble it and try.
We glued the timing cover, threw on the VC, and have it a whirl. (Made sure it was out of gear lol)
That's the point i heard the most satisfying sound i could imagine. Not only did it fire right up, it sounded glorious! Even held an idle. The roller coaster of emotions from the last couple days ended well, but I'm seriously kicking myself about that bolt. Rookie mistake. Roast away!
Current pic, I'll start cleaning up and reinstalling stuff tomorrow.
Don't feel bad, I did something similar when building my S52 E30 a decade ago. Couldn't get it to fire up for two days, it would crank and crank, build oil pressure, etc. I quadruple checked the wiring, etc. The 2nd day I finally said the hell with it and went inside and had some adult beverages, went out the next day and was like, "Didn't I change the fuel pump as well?"
Yep, sure enough. I never put the fuse for the fuel pump back in. Put it back in, the car immediately fired up and settled into a steady idle.
Don't feel bad, I did something similar when building my S52 E30 a decade ago. Couldn't get it to fire up for two days, it would crank and crank, build oil pressure, etc. I quadruple checked the wiring, etc. The 2nd day I finally said the hell with it and went inside and had some adult beverages, went out the next day and was like, "Didn't I change the fuel pump as well?"
Yep, sure enough. I never put the fuse for the fuel pump back in. Put it back in, the car immediately fired up and settled into a steady idle.
Derp derp derp
I bet that S52 e30 was fun. I've had a few BMWs in my time. good cars, but so expensive to modify! Do you still have the E30?
I did an entire wire tuck on my old NA6 which included deleting the entire airbag system and de-looming the entire harness... The bay looked incredibly clean and easy to work on, BUT the car wouldn't start initially. I triple checked everything, etc [insert many frustrated moments]. Didn't find out until a few days later than I accidentally pulled the fuel pump fuse instead of the air bag fuse.. Car started up immediately after switching it around.. [sigh]
Saturday was filled with installing the rest of my parts and diagnosing little things. I was not very good about snapping pics for this one.
The dash was reinstalled, gauges hooked up, seats installed. Clutch was bled, coolant bled. We pulled out the laptop, and started the car!
Issues we ran into:
VSS code
CKP intermittent code
O2 heater code
Gauges were geeking out. Aftermarket ones flickering, A/F gauge wouldn't power on, fuel gauge inop.
CKP intermittent code
Fans not working
The vss and o2 codes could be turned off in Kmanager. I knew the VSS wasn't set up, and the o2 heater was probably due to the inop wideband controller.
CKP on the other hand, was a hard fault that needed to be addressed. The car would start and run, but stumble after a few seconds. Some research revealed that there are two likely causes of this code, one is timing being off, the other is the trigger wheel was installed backwards.
Either way, we had to dig into the front cover again.
In our haste from monday night, one of us put the trigger wheel on backwards! Another deep sigh of relief.
From there, we attacked the fan issue. After some basic wire tracing (to make sure i hooked it up correctly), we found a blown ROOM fuse. Replaced, no further issue.
Next we spent a good deal of time working towards fixing the aftermarket gauges. To spare the blow by blow of electrical diagnosis, i'll just share some wisdom i gained. AEM widebands like their own dedicated ground. I had attempted to send a single power and ground to the vicinity of the gauges (as the other two have a daisy chain feature), but the AEM was not happy. That took a surprising amount of time to figure out! As some of you might expect, that fixed the problem with the coolant temp and oil pressure gauges as well.
Time for a test drive!
We hop in the car, and back out of the driveway. Man, this feels good. Really good. I am now about to drive something that I put together!
*SCCCCKKKKRRRPP*
Brand new exhaust scrapes really hard on my driveway. Wow, that's not ideal. Guess we are going to need to change that lol.
Overall, the drive is better than i thought. i'm on a base map, there is no intake, and the IAT has nowhere to live. It is VERY torquey, and just begs to be revved! Let's take it down the road to put it on a lift, After all, i need to get that PPF bolt in, change the fuel filter, and check things over under the car.
Test drive revealed some more issues.
Coolant temps were high.
very loud rattle coming from under the hood
Coolant leaking somewhere
after 5 minutes of driving, the car didn't want to go into gear. had to cut off the car to put it in gear.
The rattle was a 20 year old AC fan rattling against it's motor. it wouldn't come on anyway, so out you go! I figured i would need a fan solution sooner or later.
Coolant leaks were simple hose clamps at this time. Going to keep my eyes out, that seems too good to be true.
The clutch required another bleed, and pedal adjustment.
The coolant also required another bleed, and i found that the bulk heater hose used is not going to work. Theory at this time is the heater core never got full due to the pinched hoses. That will be resolved pretty soon. While the instructions mention 5/8" heater hoses, the pipe from the honda T-stat is larger, probably 3/4" (maybe 7/8"). I muscled 5/8 on there, but i really need a molded S hose with 3/4 or 7/8 on one end, and 5/8 on the other. The second hose requires a molded L bend. If you are intending to run heat, just save yourself some trouble in the beginning and source some molded hoses. You can bend a coat hanger in the approximate size and just take it to the parts store.
Test drive, take two
The drive home was pretty good, coolant temps were under control, clutch felt good. AFRs were safe, so let's feed it some revs!
The car is STRONG. Pretty smooth for a base map. VTEC is 5700, and everyone around you knows when you're in it! Didn't go much past 7200, but she wanted to!
Save that for after the tuning session, currently scheduled for 7/31. Now I have a month to sort out bugs. Am i crazy enough to attempt MATG? Would there even be a room left? Place to park the truck and trailer? Can i get the time off?
All questions for another time. I'll leave you with a couple pics.
Last year, I had a hotel room and I trailered my car down with a uhaul car hauler. I simply disconnected the trailer and parked it in the stall next to the truck for the week and there was still extra spots scattered around the resort. Nobody bothered it.
This year, I have a cabin booked and plan on driving the Miata down. I'm sure there are places you can dump a trailer. At this time, you'll probably have a harder time finding a room as I believe the resort is currently sold out, which means you'd have to go offsite to another hotel. Worth double checking availability with Fontana though!
I bet that S52 e30 was fun. I've had a few BMWs in my time. good cars, but so expensive to modify! Do you still have the E30?
It was. Had a few other mods (OBD-I, Turner headers, Porsche MAF) put down 240/240 at the wheels. Sadly it ended up being parted out. S52 popped the headgasket then found some significant rust, so said to hell with it.
Looking great! Come park it at our tent at MATG. And if you really want to put it through the paces, sign up for the Miatas Before The Gap track day on 8/1 at AMP. Good time for a proper track shakedown and you'll have the support of our whole team if you run into any teething issues.
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