Car wont start! Help!
#81
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Anyone who is savvy in this area have any input on what components this would effect and if it has caused my issue of injectors not firing? Hopefully yes so I can just throw in MS and be good to go, but if not, I'll obviously have to fix the problem before going MS
#82
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
No idea, but a search of 'f001 capacitor miata ecu' found this: For those of you with uncurable idle problems: ECU capacitor and/or diode failure - MX-5 Miata Forum
#83
Cpt. Slow
![](/mt2011/images_td/ranks/supporter1.gif)
iTrader: (25)
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,360
Total Cats: 1,184
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Flyin' Miata : Salvage
I doubt we can do much before you fix that. This is why you learn wiring basics, THEN try to tackle a wire tuck.
I doubt we can do much before you fix that. This is why you learn wiring basics, THEN try to tackle a wire tuck.
#84
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
My wire tuck was nothing. Probably the most half-*** tuck ever done. I simply unplugged, and plugged back in. I deloomed like one harness on the passenger side and seperated some wires like the tps i think and a couple others. most the wires that were tucked were for the front lights.
#85
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Okay, I put a "new" ecu in the car. It's a working ecu, but the car still doesnt start. Im not really sure what else to do. I'm going to de-loom all wiring harnesses and see if there is anything and if that doesn't show me anything ill probably just take the Car to my family mechanic and have him figure it out because there's not much else I can do
#86
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Okay, so I checked the injectors and they are getting 12v at the white/red wire. How do I check to see if the other wire is doing what it's supposed to? Do I measure continuity to ground? Or what do I do?
#91
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Okay, used a noid light, it stays on constantly. I'm not getting continuity to ground through the injector wires that go back to the ecu. I took a wire and put it directly from one injector back to it's corresponding pin on the ECU and still no continuity. So obviously I've got a ground somewhere that's messed up. Does anyone know where the ECU grounds out the injectors. So far the grounds I have found is one the back on the IM, front of the IM, 2 on the inside under the dash (passenger side) one under the brake booster. Is there any others I should be looking for? I read something about a ground right by the coil pack on the head of the motor, but I don't see anything there. Am I missing something?
#92
Boost Czar
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/admin.png)
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,688
Total Cats: 4,113
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
the ECU grounds the injectors, through the ECU.
Like I've said before, they always have 12v at the white/red wires, and the ECU grounds them to open the solenoids within and injector fuel.
If you unplug the ECU, do the non-red/white wires to the injectors go to ground?
Like I've said before, they always have 12v at the white/red wires, and the ECU grounds them to open the solenoids within and injector fuel.
If you unplug the ECU, do the non-red/white wires to the injectors go to ground?
#93
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
No. I've been checking continuity from the wire at the injector to it's spot on the plug to the ECU. All of them are good. So I assume there is a ground from the ECU that is not getting grounded properly?
#98
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I took the noid light, stuck it in the injector connector, had my buddy crank the car, light stayed on. I know this seems contradictory to my situation, because I can assure you the injectors are not firing. When I remove them after cranking there is no fuel on them and the plugs are dry. Also, I believe my starter has now gone bad from the multpile attempts to get the car started over the last 2 months. Is there anywhere to purchase a full wiring harness for my car or a place that would custom make one. Some of the wires are not in very good shape, like around the coil packs and injectors and what not. I pulled the entire harness from the ECU through the passenger side firewall and they all seem to be in working order, just some are in rough condition. I cannot find a break or any sort of discrepancy in any of the wires
#99
Junior Member
Thread Starter
iTrader: (1)
Join Date: Feb 2013
Location: Cape Coral, FL
Posts: 155
Total Cats: 1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I've de-loomed the entire passenger side engine harness and haven't found anything significant. There was once spot that seemed questionable "where a black wire met with a grey wire and a red wire but there was nothing that was split, just a little pinched. When I re-assembled the wiring harness the other day, I turned the key to try and start the car again and the tach raised to about 3500 rpm. It did this everytime I turned the key to RUN. I disconnected the battery and held the brake to reset the ECU and it did not do this anymore afterwards..