First Start-No Injectors

[tkmhkm]

As the title says I got the VH45 In and mounted with the 5 speed and the motor cranks and sounds great but I am not getting fuel into the cylinders. I have checked the line pressure and everything is good there. It would seem that my injectors are not firing. When I get home later I plan to check the Ohm's at each injector to make sure they are good. I did a painless wiring job on the car though so all the wiring is by hand and cleaned up. Things I might have different is I that I have all the ecu 12V +'s wired to 12v constant when key is in. (Does the EUC Start signal need the 12V+ start or is constant fine?) I will type up a data sheet showing how I have the ecu's blue connector wired tonight when I get home. Just wanted to hear from other vh45 swappers what else I could check on the blue/brown/white ecu harness that might cause a no injector fire or any other test I could perform to see what may be the problem.

Thanks in advance for any help/input.

[tkmhkm]

Ok just checked my wiring and this is how I have the 12V +'s wired on the blue connector:

ECCS Relay has 12v+ constant 25A
large Red on Blue Connector (Injectors) 12v+ 25A
Green/Blk Stripe on Blue Connector (Strt Singnal) 12v+ Constant
Large Blk/White Stripe on Blue Connector (Ign. Start) 12v+ Constant
Green/Red Stripe on Blue Connector (Ign on or Start) 12v+ Constant

In the wiring diagram it looks like they have Green/Blk Stripe wired to Blk/Red on Ign. Switch which if I remember correctly is the 12v+ start not constant.

Also Im having problems getting a Ohm reading on injectors, anyone ever checked there injectors and can explain a little better then the service page.

Thanks

[Bart]

What I would do first is get an LED light with a 100 ohm resistor connected to it, plug this into the injector plug (unplug the loom from the injector first) turn the engine over and the LED from memory should flash. If not check wiring
The resistance on the injector is very small 11ohms i think for SR20 engines
SR20 and other injector
http://www.sdsefi.com/injectors.htm

[tkmhkm]

Thanks, I will try the led tonight when I get home. I will make up the led & resistor wiring while I’m here at work. The only thing I found wrong in how I had it wired is that I had the ECU's green blk start signal wired to a constant 12v when it was supposed to only see 12v during start and not run.
If while turning the key while starting if the led does not flash I’m assuming then bad harness or ecu right? I have traced all injector wires back to main ecu plug so harness is good so I am down to ecu or injector failure.

[Bart]

Assuming your wiring is all good then possibly injector and or ecu

[tkmhkm]

Ok finally got to do more tests this morning. Got all the wiring checked and looks good. Did an ohm test on the injectors following http://www.q45.org/ohminjectors.html tutorial and could not get a reading. If I switched the black and red probe then all the injectors read 1.1-1.4 mOhms. Made the led circuit and tried it but if I tried it on the injector plug on just one prong got nothing. If trying to put tester to both injector prongs I would get sparks? It looks like per FSM the injectors get constanct 12v and then a switched 12v signal from the ECU to fire. At this point Im out to hire anyones services in the NC, area that can swing by some time and solve this. $$ to the one who can come fix this or offer up the fixed solution. I have got to get this figured out soon.

[Bart]

This is like using an LED, connected in the same points
http://www.youtube.com/watch?v=1rBhdgWSFks

You shouldnt get sparks, 12v turns on and off, basically flashes the light on and off very quickly

[tkmhkm]

OK I just took all 8 injectors out and cleaned them. Built a home injector test/clean circuit. Took a used 12v car battery and hooked up a ground to the injector and the positive with a momentary push button and light so I knew when power was being supplied and tested the injector circuit and all the injectors fired/clicked. Gonna make a cleaning unit next to soak/spray cleaner through them. Gonna check wiring again something has to be wrong if they work out of car but not in.

[tkmhkm]

Did led test light again 3 different ways and still no light. Spark plugs are firing and fuel pump relay from ecu is working so ECU should be good. I even ran a direct test from the ECU injectors out to ground on the led and still no light. But the led and injectors work fine on my home test circuit. It looks like the ECU might be sending a positive signal to the fuel injectors when it should be sending ground to close the circuit. Back to wiring....arggggg....

[tkmhkm]

Ok finally got done checking the wiring and have some updates that might help solve this issue. Checked the CAS wiring and signal as well as the TPS wiring and signal to make sure that the ECU was getting a good signal from both to be able to start. I am still working on testing every other signal circuit on the ECU but at this point I can do the LED test and get some interesting results that I need someone to verify is correct. I plug the + lead on led into the constant injector 12v and then the ground into the ECU signal wire and the led has a faint glow that will flash now and again when trying to crank which seems to me that the ECU is now sending a proper signal to fire the injectors. Hooked up the injector rail and did a test fire to see if any would and still no squirt so I’m going replace injectors with 94+ models (better life span with ethanol mixed gas so I hear). So am I on the right track or am I still shooting around in the dark on this one. Thanks

[Bart]

Ok finally got done checking the wiring and have some updates that might help solve this issue. Checked the CAS wiring and signal as well as the TPS wiring and signal to make sure that the ECU was getting a good signal from both to be able to start. I am still working on testing every other signal circuit on the ECU but at this point I can do the LED test and get some interesting results that I need someone to verify is correct. I plug the + lead on led into the constant injector 12v and then the ground into the ECU signal wire and the led has a faint glow that will flash now and again when trying to crank which seems to me that the ECU is now sending a proper signal to fire the injectors. Hooked up the injector rail and did a test fire to see if any would and still no squirt so I’m going replace injectors with 94+ models (better life span with ethanol mixed gas so I hear). So am I on the right track or am I still shooting around in the dark on this one. Thanks

Last i did the led test i plugged it into the injector loom only and got a good signal, not faint glow. But hey it may be ok

[lyon23]

Maybe I missed it in on of your posts but have you checked your grounds. Specially the ones for the ecu.

[tkmhkm]

Ok here is this last weekend’s update for all who are following this. I did the led test with it plug into just the injector 2 prong plug/harness and got the same results. I went around and sanded/cleaned all of my grounds and then did a ground DC volt test. On all of the engine and ECU grounds I got a good signal with a 0.0V reading for no leakage. If I checked the grounds on the injector harness all the way back to the ECU outputs I got a 1-1.2V reading meaning that the ground signal from the ECU to the injectors might be a problem. It will not be until next weekend when I have the new injectors and ECU to try out but I am going to keep messing around with this setup in the meantime. I did manage to get 3 of the injectors to fire but not constantly like they should. I’m going to set them up with a trigger and some cleaning solution and try to run a cleaner through them for about 4 hrs and see if it helps any of them fire like they should.

[chharith]

I hope I do not run into this problem.