spork Posted July 2, 2006 Share Posted July 2, 2006 I've got an em4-6f system and have been trying to trouble shoot the car and I'm stuck. The car won't start. I checked all fuses with a ohm meter, the coils are firing (all 3 coils), and there is 12V present at the injector plugs. The injectors don't fire when cranking tho. I tried a noid light to verify this and I was correct. If I test fire them with a jumper wire they click and work (connect the proper wire to ground). I assume this can't be a hall sensor problem as I'm getting coil fire. What should I check next? I unplugged all the injector harness wires and checked for any sort of corrosion and found none. I don't know if this is worth mentioning or not, but I washed the car about an hour earlier (but not the engine bay). I frove it and stopped for lunch, started the car right up, drove out of the parking lot and then it died right as I pulled out on to the street. Let me know what I need to look for, I'm running out of ideas. Quote Link to comment Share on other sites More sharing options...
slownrusty Posted July 3, 2006 Share Posted July 3, 2006 James - You could PM Austin as he has the same SDS set-up as you, -or- call SDS they have excellent customer service. If that does not work, I have an aquaintence in Toronto who has done a few SDS installs in Zs and he is a great guy that can help you out. Yasin Quote Link to comment Share on other sites More sharing options...
Nigel Posted July 3, 2006 Share Posted July 3, 2006 Are you getting 12V on the injector wires at the connector on the ECU ? It's the white nylon plug. Three of the wires going into it are for the injectors (one for every 2 injectors). If you're getting 12V there then the circuit is complete, and the transistors in the ECU aren't switching on for some reason. Where's the ECU? Any chance water could have leaked onto it when the car was washed? Nigel '73 240ZT Quote Link to comment Share on other sites More sharing options...
spork Posted July 3, 2006 Author Share Posted July 3, 2006 SDS is closed till tomorrow due to the canadian holiday,and I've been hoping to get the car working since its been down so long (put a new clutch in). The ecu has power on the appropriate wires, but just won't ground the ground wire to fire the injectors. I really think the injector driver circuit in the ecu just up and died for some reason. The ecu is inside the car and there were no signs of water ever getting on it. I checked real good because I was thinking the same thing. The carpet around it was all dry as well. I'm pretty sure I know it'll need sent in for repairs, but it's the last thing I really want to do, and I sure don't want to send it in to find out there is nothing wrong with it! Hey, jut checked the power wires again. I've got 2 black wires from the white plastic plug that go to ground, then 3 wires (red, white, and black) all 3 wires had power. I tried cranking the engine and it won't start. I test fired the injectors with the fuel pump running to spray fuel into the engine. I then tried starting the car and it started...and stayed running. I let it run for awhile while cleaning up tools, and doing some other misc items. I go back to the car after 10-15minutes, get reasy to pull it out of the driveway and the engine dies suddenly...wtf? No sputtering or anything just quits running like I had grabbed the key and shut it off. I tried cranking, and it didn't even try to fire. So I decided, what the hell, I'll ground the injectors again and see if it'll start after manually putting fuel in again. It started and ran for about 30 seconds and then suddenly stopped. Now I can't get it to start and run again no matter what I do. It'll sputter if I ground an injector, but it won't actually run. I have power to all 3 wires for the injectors on the ecu now when it doesn't run again. I'll pull the ground wires and clean them again just incase...but I'm lost here. It can't be a hot start problem because the car sat all night and wouldn't start until I manually fired the injectors. It got warmed up then quit. Maybe something is causing the circuits to stick when they get hot and I got them to unstick by manually firing the injectors? Is that even possible? Now I'm afraid if I send in my ecu, they'll send it back and say everything is working fine for them. Quote Link to comment Share on other sites More sharing options...
Drax240z Posted July 4, 2006 Share Posted July 4, 2006 I had something similar happen... turned out I had picked up power for my fuel pump relay through the circuit that worked the seatbelt light. Every time I got in to drive away, I put on my seatbelt, and the car died. Took a while to find it. You sure something similar isn't happening? I'm sure you didn't do the same thing, but it just shows how easy it is to overlook something and think your problems are elsewhere... Quote Link to comment Share on other sites More sharing options...
spork Posted July 4, 2006 Author Share Posted July 4, 2006 well, I've had the car driving for almost 4 years with the SDS so I doubt something like that happened, but I suppose anything is possible...lol. I do have power to all my wires going to the sds while the ignition is on, and also while it's cranking so it should be okay to atleast start. I guess I'll see if I can get ahold of sds later today and see what they say. Quote Link to comment Share on other sites More sharing options...
240hoke Posted July 4, 2006 Share Posted July 4, 2006 I know its dumb, but I thought I would mention. Did you check the continuity of your ground to the battery negitive terminal? Even if it clean you could just have a weak spot for a ground. Where is your resistor pack mounted for your injectors? Have you checked it? That is if you are running low impedence. Quote Link to comment Share on other sites More sharing options...
spork Posted July 4, 2006 Author Share Posted July 4, 2006 I just got off the phone with Barry at SDS. Thier tech support is awesome. After talking things over, we found that the map sensor was reading full vaccum and so it wasn't getting any fuel. I found a wire that got pinched inside a harness and eventually grounded out. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.