D jet troubleshooting question, determining a probable wiring fault. |
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D jet troubleshooting question, determining a probable wiring fault. |
Lowsquire |
Sep 11 2016, 07:09 PM
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#1
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Newbie Group: Members Posts: 20 Joined: 23-April 16 From: Austin Texas Member No.: 19,926 Region Association: Southwest Region |
Hi all you D-jet Gurus out there..
Heres the problem I have ,hope you can help. 73 1.7 stock car. Hasnt run in many years I assume , I Bought it with everything removed and off the top of the motor. all the parts looked cleaned and (maybe?) checked or reconditioned. they may have just been wiped clean and put in bags? who knows? Ive just got the whole thing back together and ready to start.lt Cranks over, fuel pressure, good spark..would almost catch , but not quite fire. Through checking spark plugs and swapping injector plugs around, worked out I was only getting fuel out of one injector. Confirmed this by pulling injectors, then operating throttle with ignition on, which allows the enrichment circuit to fire the injector, and you hear a series of clicks from injector. Only one out of the four injector plugs seem to make the injector click.when i swapped the plug onto another injector that clicked fine and sprayed fuel,indicating injectors are fine. SO next i checked and cleaned injector wire ground points and checked continuity to ground to the wires, and they all behaved the same, seemingly fine. so where im at is working out if its possible that the computer is fritzed and only firing the one injector, or if its a fault in the loom. I guess my question is.. does the signal to fire the injectors come out of the brain as four seperate wires, or two then split to the two banks, or a single terminal and split in the loom somewhere? a diagram of the connector pins would be a great start.. I guess stripping the loom out is next and checking for any breaks/poor connections. |
Lowsquire |
Sep 11 2016, 09:43 PM
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#2
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Newbie Group: Members Posts: 20 Joined: 23-April 16 From: Austin Texas Member No.: 19,926 Region Association: Southwest Region |
Thanks this is all great stuff!
to clarify, the injectors all operate correctly, i swapped them over one by one onto the operating connector and they all spray what looks to be a good pattern, no leaking . yup im going to go through every component and test. I guess thats the price of buying a car with stripped incomplete engine, and no idea when it last ran ! I guess i can count my luck in that it has good compression and oil pressure ( at crank speeds anyway!) |
pbanders |
Sep 11 2016, 10:51 PM
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#3
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Senior Member Group: Members Posts: 939 Joined: 11-June 03 From: Phoenix, AZ Member No.: 805 |
Thanks this is all great stuff! to clarify, the injectors all operate correctly, i swapped them over one by one onto the operating connector and they all spray what looks to be a good pattern, no leaking . yup im going to go through every component and test. I guess thats the price of buying a car with stripped incomplete engine, and no idea when it last ran ! I guess i can count my luck in that it has good compression and oil pressure ( at crank speeds anyway!) If all your injectors work when tested on your one good plug, then even if the injector driver circuit for one injector group was bad, you'd still have one operating injector group (two injector plugs). From how you describe it, I suggest that you have a wiring fault in the harness, which could be due to an open wire, faulty injector plug, faulty ECU plug, or faulty multi-point ground. It should be a straightforward process to check all of these with a multimeter. If everything checks out good, then you have an ECU fault in one of the injector groups. Take a look at my page (in my sig file) for descriptions on the ECU and system connections for D-Jet if you need more help. |
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