76 D-jetronics problems, Only one injector working |
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76 D-jetronics problems, Only one injector working |
Malpais82e |
Jun 5 2013, 08:53 AM
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#1
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Newbie Group: Members Posts: 12 Joined: 4-June 13 From: Fort Collins Colorado Member No.: 15,968 Region Association: Rocky Mountains |
I have a 76 914 that's been in my barn for 10 years. Trying to get it running again. I’ve searched this forum and other forums and the internet extensively, and can’t find an answer, or don’t recognize it!
My questions are: 1: Can bad or maladjusted trigger points shut down 3 injectors and allow one to work? 2: If the throttle switch, when throttle is stroked, cycles one injector about 20 times, shouldn’t it make all injectors click? Just one does. 3: Does the throttle switch bypass the Control Unit or at least the computing in the Control Unit? What I’ve done so far: Sprayed gasoline into the throttle body. Ignition system and timing work – thing runs and sounds good. The relay board and sockets needed cleaning, and I got the relays working so the Fuel Pump and control module have power as I’ve read they should. Fuel pump runs a few second when key is turned on. Pressure is about 30 psi. I’ve also read that moving the throttle (and switch) should, cause the injectors to “click”). Only #4 cylinder injector does anything. I then re-did the grounds and rang out the wires to all injectors - grounds to ground and power wires to appropriate connections on the Control Unit - all had continuity. I took the injectors out and sure enough, only #4 sprays gasoline. If I move the #4 wires to another injector, it works, so only #4 connector is getting a signal and at least one other injector will work if it had a signal. The rest won't even click. I tried a different control unit – same symptoms and only #4 injector doing anything! I'm thinking of trigger points, but if they are bad/misadjusted, a pair of cylinders would fail instead of three, wouldn't they? And bad trigger points wouldn't keep the throttle switch from cycling all four injectors, would it? Thanks for any ideas or guidance. I’m about frustrated and out of ideas. Maybe a little a little dynamite…………………………. Gordon |
Jesco Reient |
Dec 5 2013, 08:01 PM
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#2
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Member Group: Members Posts: 135 Joined: 18-July 12 From: Western Washington Member No.: 14,690 Region Association: Pacific Northwest |
Malpais82e,
What was the final resolution to this problem? My wife's 914 is now doing the exact thing yours started out doing. The only injector that clicks with the throttle switch is number 2. Number 3 does not click when number 2 is clicking which it should because the trigger points are the same for numbers 2 & 3. When I turn the engine 180 degrees onto the other side of the trigger points neither numbers 1 nor number 4 make any clicking noise when the throttle switch is moved. I had the injectors cleaned, tested, and flowed by Marren Fuel injection so I really don't think that the injectors are the issue. The harness when I had it out of the car was rebuilt by my self and all of the wires tested correct for continuity I replaced any damaged boots and harness ends. I'm left with the belief that the injector points are bad on the 1-4 side, and the grounds are not connected securely on the 3-4 circuit. But since they were acting the same I thought I'd ask what you found? Thank you |
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