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Help locating fuel injector

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My SPFI car has an injector that I need to locate. I'm not sure I'm looking at the correct part in the carb.... there isn't anything that looks like a typical injector, here.

 

If you're standing in front of the car, looking into the bay, the part I'm looking at is on the right side of the carb. It's rather large and blockish.... there are two (2) wires going into it. Is this the correct part?

 

If so, what wire is negative (-)?

 

This is a 1992 Loyale, and my remote starter is having issues due to the cold weather..... it thinks it's over-reving on a cold morning start.

 

TIA,

Todd

Yeah they will keep climbing until you pump the gas I think. Get off your butt and go start it yourself:brow: . Seriously, the injectors will be on the fuel rail and will have a wire plug set up going to them. Just chase the fuel lines to either side and you're there right where they go into the manifold.

  • Author

the injectors will be on the fuel rail and will have a wire plug set up going to them. Just chase the fuel lines to either side and you're there right where they go into the manifold.

 

This car will have a fuel rail, even if there's only one injector? I remember my old Ford had an injector firing directly down the carbs throat. I haven't looked that this car too extensively.

 

Any clue what color is negative?

 

Thanks

First - there is no carb. Its fuel injected;)

Second - the fuel injector sits right inside the throttlebody, in the middle. Pull the air intake tube and you will see where the wires go into the top of the injector.

 

No idea which wire is which.. been a couple years since I pulled an injector from an SPFI car.

forgive my ignorance... but why does the remote starter need to know about the fuel injector/rpms? It seems like all it should do is start the car, then let the computer worry about making the engine run? Does it have some emergency cut off if the idle or such goes too high?

 

How high is it idling when it's cold?

  • Author

Thanks for making me feel like an a$$, lol.

 

I'll go out in a few.

 

Thanks

  • Author
why does the remote starter need to know about the fuel injector/rpms?

 

It needs a tach signal to let it know that the car is running. This needs to be programed after instalation.

 

 

Does it have some emergency cut off if the idle or such goes too high?

 

Yes, it will shut the car down if it seems to be over-reving. It will also try to restart the car, if the rpms are too low.... it won't register the car as running.

 

 

How high is it idling when it's cold?

 

Maybe 2500-2800 rpms(?); not absolutely sure. On my last car, (a VW Rabbit), I wired a solenoid to pull on the gas pedal after the car started. This would bring down the rpms when in choke mode. I could do the same, but the tech line I called just said to try the injector wiring.... seems much easier. I'll use the solenoid as plan "B".

 

-Todd

It needs a tach signal to let it know that the car is running. This needs to be programed after instalation.

 

Yes, it will shut the car down if it seems to be over-reving. It will also try to restart the car, if the rpms are too low.... it won't register the car as running.

 

Maybe 2500-2800 rpms(?); not absolutely sure. On my last car, (a VW Rabbit), I wired a solenoid to pull on the gas pedal after the car started. This would bring down the rpms when in choke mode. I could do the same, but the tech line I called just said to try the injector wiring.... seems much easier. I'll use the solenoid as plan "B".

 

-Todd

 

ahh, makes sense now, I have been informed :grin:

 

couple more questions...

So the tech line is having you tap into the injector wiring with their remote starter bring the idle down? :confused Just trying to understand what they're telling you... Given enough time the computer will kick the idle down automatically.

What remote starter is it so I can look at the installation guide also? (I've been meaning to add one to my car anyways)

 

(sorry if I was the one that made you feel like an @ss, I'm just curious about why the starter needed the fuel injector stuff :))

  • Author

So the tech line is having you tap into the injector wiring with their remote starter bring the idle down?

 

No, it won't bring the idle down, but my understanding is that the injector pulses are not as high as the reading from the coil.

 

what remote starter is it so I can look at the installation guide also?

 

This is a Prestige APS-996. I've used some other brands such as Bulldog, and this seems to be the best yet. Great range, too. I used a APS-995 on the VW, and the only difference was the remote.

 

http://www.audiovox.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10001&storeId=10001&productId=12870&langId=-1

 

sorry if I was the one that made you feel like an @ss

 

not you, but the one who said it wasn't a carb, but a t/b, lol.

 

-Todd

No, it won't bring the idle down, but my understanding is that the injector pulses are not as high as the reading from the coil.

 

not as high meaning; lower voltage, or not as fast of rpms? I'm not sure how the injector pulse rate corresponds to the rpms. Looking through the manual, it looks like you can just connect the tach input to the negative side of the coil and be done with it? That's where the connection to the dash tach comes from.

 

But to answer your original question about the polarity on the injector; unplug the injector (only two pin connector that goes into the throttle body), turn the key to on (not start), and measure the voltage on the two pins going to the body harness. One should be 12v, and the other should be 0v or floating. These cars use a switched ground system, so the hot lead is always hot.

  • Author
not as high meaning; lower voltage, or not as fast of rpms? I'm not sure how the injector pulse rate corresponds to the rpms. Looking through the manual, it looks like you can just connect the tach input to the negative side of the coil and be done with it?

 

I really don't know what the difference would be.... maybe someone with better knowlege on this could chime in.... I'm used to mechanical fuel injection (Bosch CIS).

 

Looking through the manual, it looks like you can just connect the tach input to the negative side of the coil and be done with it? That's where the connection to the dash tach comes from.

 

I have it hooked directly to the coil now, and it's shutting the car down. It works fine when it's warmer outside or the car is warm.

 

Thanks for the polarity tip. I was under the hood and pulled the t/b boot. I'm assuming the injector is under the bulbous thing that I thought was for the venturi purpose. I see the thin black harness and see that it goes to a 2 wire plug as you describe. One wire is red/ black and the other is red/ white. This has to be it... I'll try to do the procedure today and post results.

 

Thanks,

Todd

I have it hooked directly to the coil now, and it's shutting the car down. It works fine when it's warmer outside or the car is warm.

 

Thanks,

Todd

 

I presume you have it hooked up the negative side of the coil?

 

Have you tried re-doing the programming on it when it's cold, so it 'learns' the higher idle? (I'm looking at page 20 of the installation guide)

 

Not sure what that would do when it got warm outside again and the car doesn't need to idle as high though...

  • Author

Yes, it's hooked up to the negative side of the coil.

 

I had it programed to the higher idle, but when the car was warm, it would re-engage the starter, because the tach signal was too low to be detected.

well then... looks like you found a bug in their system. I wonder how that starter works on every other car, that I imagine would have a higher idle when cold as well? Or do they just have better computers that hold a certain rpm to warm up?

 

And to be perfectly honest, I have no idea why they would have suggested to tap into the fuel injector pulses. Unless I'm mistaken (could be) higher idle = faster fuel injector pulses, lower idle = lower fuel injector... etc... you'd run into the same problem you have now.

 

hmm... I'm contemplating a little electronic device that would take a variable rpm in, and spit out a certain rpm... That would allow the computer to control the engine idle, and would let the remote starter know that it's running... I'll have to ponder this...

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