ISPKI Posted November 15, 2013 Author Share Posted November 15, 2013 ECU looks brand new inside. I was scrounging around and found two disconnected wires over on the passenger side dangling down from where the engine harness comes through the firewall. One was white with a red stripe and the other was solid blue, about 14ga, both had bullet connectors. Not really sure where these are supposed to go but the white/red striped wire has continuity to the large wire going to the alternator from the battery. No idea where the blue wire goes but seems really odd - those white/red stripe wires are usually really important... Will investigate more when I get into it this weekend. I just had to fabricate a new exhaust system for my honda civic before winter hits so that has been sucking away alot of my time. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 16, 2013 Author Share Posted November 16, 2013 Here are a few shots of the wires that I am trying to figure out. One is a bullet connector, the other is a spade connector, both female. I can find where they are supposed to go. This is on the passenger side. I also found a plug disconnected on one of the relays in that cluster on the passenger side, above the fuse box. A 6 pin connector with 3 pins in it. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 16, 2013 Author Share Posted November 16, 2013 (edited) AH hah, Found it. looks like they go to cooling fan sub harness - BE-95, Detail E, #16. Quick question: Is the side of the main ignition relay that switches on when the key is turned to "start" supposed to stay closed while the key is turned or is it supposed to click very quickly? Edited November 16, 2013 by ISPKI Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 16, 2013 Author Share Posted November 16, 2013 I went through and started testing the AFM via the "engine will not start" section of the EFI bible. Testing for resistance on the various circuits going through it. I am not entirely sure I am doing this correctly as the voltmeter reads 0 or 001 on all tests. When testing for resistance on these circuits (lets say the air temp circuit - should read 100 ohms) I should set my volt meter to "200" on the dial correct? And when testing for water temperature resistance, (should read around 2250-2750 ohms) I should have the dial set to "2000" correct? That is what I did and it failed on all tests except continuity from pin 8 to pin 9. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 17, 2013 Author Share Posted November 17, 2013 OK. So I was walking through the EFI bible, went to test the water temp sensor resistance again (Pin 13 to ground). This has been really confusing because my AFM had zero resistance when I tested it and now the water temp sensor also has no resistance (should be around 3000ish). I went to test the wires at the sensor to see if they were connected properly which they did not seem to be. It looked like the wires for the water temp sensor and the thermotime switch were switched. Here is where it gets interesting. I switch the plugs to they appear to be going to the correct sensor, then I unplug one of the quick disconnects for the water temp sensor (the wire that has "13" printed on it) and test continuity from pin 13 on the ECM to that wire - should read continuity and it does. I then unplug the other wire and for some reason I decide to test continuity from the #13 wire at the sensor to the #13 pin on the ECM plug again - no continuity... I plug the opposite wire back in and retest #13 wire to #13 pin at ECM, and I have continuity... I then unplugged both wires going to the water temp sensor and the plug for the thermotime switch and then tested continuity from pin13 to ground and I have continuity... This is telling me that somewhere in this harness, the #13 wire is contacting ground which explains why I cant get a resistance reading from the water temp gauge. Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 18, 2013 Share Posted November 18, 2013 The water temp gauge has nothing to do with the water temp sensor. The gauge uses a completely different sender and wire. What kind of meter are you using? 0 and 001 don't sound right (Post 44). Find something of known resistance, like an old injector or the AAR, and measure it. An injector will be about 2.5 ohms, the AAR about 60. And the setting on the meter needs to be high than what you expect. The 2000 ohm range won't measure over 2000 ohms. That might explain the 001. Does the meter have instructions with it? Search around the internet for "how to measure resistance" or "how to use a multimeter". You need a little bit of training. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 18, 2013 Author Share Posted November 18, 2013 (edited) I havent done anything regarding the water temp gauge or the transmitter, I was only working with the water temp sensor. I was getting confused with the multimeter because the #13 wire from the ECM plug wasnt reading any resistance - or very very little. Then I found that the #13 wire had continuity to ground when disconnected from the water temp sensor which is telling me that the wire must be broken somewhere and contacting the body or other wires. I tried measuring it on the 200, 2000, and 20000 settings with the same results, almost no resistance. From what I read online, the "2000" setting should read anything in the 4-digit range, the "20000" would read anything in the 5 digit range. Edited November 18, 2013 by ISPKI Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 18, 2013 Author Share Posted November 18, 2013 (edited) Got some testing done on the car today. Found some goofy wiring with the thermotime switch and water temp sensor wires. Straightened that out and I now have 2950 ohms from the water temp sensor with the ambient temperature being around 60ish so that seems to be passing. I continued on and performed the AFM circuit tests detailed after the power relay control unit tests. Tests 1-3a, 3b, and 3c. I was testing at the ECM plug and the resistance values were all somewhat high. I have 260ohm from pins 8-6, book calls for 180ohms. I have 225ohm from pins 8-7, book calls for 100. I have 145ohm for pins 8-9, book calls for very low resistance (no value). Again I was testing those at the ECM plug, not at the AFM terminals, so I would expect the resistance to be a little bit higher but those seem abnormally high, not sure if that would prevent it from starting but I will pull the AFM out and test the terminals at the AFM in the upcoming days if I get the time (doing brakes on my scion TC tomorrow so not sure when that will be). Oh, I did do the next test as well 3-(3): testing Pin 21 to ground, should have battery voltage within 15 seconds of key being in "start" position. That test failed, it stayed at 0 voltage. This is leading me to believe that there is something going on with the power relay or the ignition switch since power should be supplied through the power relay. I will test for power at the wire going in to the cold start valve next time I get to work on the car just to make sure that the relay is actually functioning, however, I have the cover off the relay, and the "start" side of the relay did not close when I held the key to the "start" position and when i have the wire to the starter solenoid connected, the "start" side of the relay clicks and sparks very quickly rather than staying closed. I supposed I could carefully hold the start side of the relay closed and try the test again to see if it works. Edited November 18, 2013 by ISPKI Quote Link to comment Share on other sites More sharing options...
ISPKI Posted November 19, 2013 Author Share Posted November 19, 2013 I pulled the Main Ignition relay out of the vehicle to run some tests on it according to page EF-55 section 7-1. I wired up a jumper wire from Pin 86c (+) and 85 (-) to a battery pack that I have for jumping cars. When supplied power from the battery pack, the relay passes the first test of having continuity between pin 88z and 88a, and has continuity between 88b and 88z. Moving down to the next test for the fuel pump, the relay fails to have continuity between 88y and 88d. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted December 2, 2013 Author Share Posted December 2, 2013 Picked up a replacement relay from a gentleman on here. Tested it before putting it in the car, passed all tests from the FSM. Bolted it into the car and it still won't stay running. Starts for a second after sitting overnight and then won't start again. Quote Link to comment Share on other sites More sharing options...
nismosilvia Posted December 29, 2013 Share Posted December 29, 2013 You sure you've got fuel to the injectors? Efi harness is grounded properly etc. I read this thread you've done a lot of testing so I'm stumped your still having problems there's not much to these systems. If the wire to the boost controll deceleration device is unplugged your car won't run period. Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 29, 2013 Share Posted December 29, 2013 Many people remove the BCDD entirely and their engines still run. Not sure your statement is correct. Quote Link to comment Share on other sites More sharing options...
ISPKI Posted December 30, 2013 Author Share Posted December 30, 2013 Yes, I tried starting with and without the BCDD plugged in. Made no difference. To give you guys an idea of the wiring situation I am dealing with here, the BCDD was plugged into the AC compressor when I first got the vehicle D: I havent been able to work on it in over a month, have it buttoned up for winter. I will be moving into my first house in about 1 month and it has a garage so I will be able to do some serious trouble diagnostics on it. The injectors are getting fuel, I can fire them manually and they shoot fuel out when I do, its just that the ECU is behaving as though it is not getting a signal to pulse the injectors, the injectors just sit with 12v all the time and they never ground when starting. It has continuity from the - post on the coil to the ECU (dont remember which pin, I think it was pin 1 from - coil post) but I never checked if there is actually a signal from the - coil post, I only checked continuity. Not really sure why it wouldnt pulse, perhaps the ICM on the dizzy is faulty? It is one of the few things I have not really checked. Quote Link to comment Share on other sites More sharing options...
nismosilvia Posted December 30, 2013 Share Posted December 30, 2013 Newzed. Maybe they remove them for megasquirt and its fine. Mines all plugged off but if the sensor wire is unplugged my car will die and not start, plug the wire back in and it will start. I'm on the stock ecu by the way Quote Link to comment Share on other sites More sharing options...
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