Stuck Injector
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From: Aurora, Ontario, Canada
Should add that these are reconditioned and matched...so I'm not anticipating there's a mechanical issue with the injector, and the noid light shows good signal. Connection has been checked. What voltage do these normally run at? (Can it be jumpered to check operation)?
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From: Aurora, Ontario, Canada
Troubleshooting
Long story short, isolated why injector circuit #1 was going out. Stethescope indictates number 4 injector not firing which is causing the circuit to shut down under load.
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Under load and or heat are hard faults to isolate for sure.
You could swap it to the other Injector circuit and see if the same problem follows your theory else just swap it out with another known good one.
What does that cylinders spark plug look like?
You could swap it to the other Injector circuit and see if the same problem follows your theory else just swap it out with another known good one.
What does that cylinders spark plug look like?
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From: Aurora, Ontario, Canada
All Good
Spark is nice and strong - fresh plugs and good wires. Seems like a couple of the others were a little sticky at first but fine now. This one just won't co-operate. I'll try and coax it with the 9V battery before I take out the rail again.
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12V next.
12V is next. I'm beginning to think the coil is defective.
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From: AZ
The fuel injectors are all wired in parallel. Battery voltage is provided when the ignition is turned on (1987 and newer) or when the fuel pump runs (1984 Euro though 1986 Euro/US). In all cases the LH provides the switch to ground (via a power transistor) with a good size capacitor there to handle the voltage spike.
Have you checked the resistance of the fuel injector? It should be in the 14 ohm range. As you might imagine, with only 14 ohms a good amount current flows with 12V across it - so don't leave it connected to a battery for any long amount of time or you can cook the coil windings. If it doesn't open, it is dead.
Have you checked the resistance of the fuel injector? It should be in the 14 ohm range. As you might imagine, with only 14 ohms a good amount current flows with 12V across it - so don't leave it connected to a battery for any long amount of time or you can cook the coil windings. If it doesn't open, it is dead.
Captain Obvious
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Ahhhh you finally found the problem. Glad to hear it.
If a 9V won't open it, then 12 probably won't either but worth a try. As a last resort, swap it out with the old one untill you get a replacement.
If a 9V won't open it, then 12 probably won't either but worth a try. As a last resort, swap it out with the old one untill you get a replacement.
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From: Aurora, Ontario, Canada
Hey Imre!
Giving up now, it's been flushed with cleaner and pulsed with 12V with no response.
All old ones are clacking happily with the 9V, but for the sake of a couple days, I'm going to wait on the replacement and then button it up. Should be operational by the weekend. (Which would give me an excuse to criuse over to your place and be a nuisance)!
Soon,
