fuel injectors...

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DavidT

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What are some symptoms that they are not working up to par?
 

Anthony1238

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If the Injector is clogged or some how failed... it will bogg down, big loss of power, almost like there is no spark... to check if the injector is working use a long screwdriver, (i used a mechanics stethasope) Put the tip of the screwdriver on the electrical connector that connects the to the injector and listen for a ticking noise... this means it works, if it doesn't tick this means it is clogged or has failed.
 

rangerj

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DavidT,

For a couple of dollars at Auto Zone, or a parts store, you can get a "NOID" light. It plugs into the electrical connection of the injector harness.

The light will blink if it is getting electricity.(KOER)

Next listen to the injector as it operates, either using a mechanics stethescope, or a screwdriver.(KOER)

The injector clicks as it opens and closes the pintel. If the injectors are working electrically and mechanically, but you still think they may be clogged or otherwise defective, remove them and have them cleaned and/or reconditioned. rangerj
 

Dr.Evil

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would a bad or semi-cloged injector cause an overall loss in power? Meaning lower output throughout the RPM range, but still have some power but just not SHO power? Also, how can you tell if it is shooting the right amount of fuel?
 

Bizzy

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Dr.Evil:
would a bad or semi-cloged injector cause an overall loss in power? Meaning lower output throughout the RPM range, but still have some power but just not SHO power? Also, how can you tell if it is shooting the right amount of fuel?
I don't think there is any way for the every day person to tell if it's shooting the proper amount of fuel or not. There are testing facilities around that can do this for you though.

I think that every car, or injector could be different depending on exactly how badly it is clogged. Some might experience just sputters while I'm sure that a really clogged set would result in an overall loss of power.
 

twr

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If you suspect a bad injector, the cylinder balance test (after KOER) is very helpful. Run the test, if it returns a cylinder number, swap that injector to a different cylinder and run the test again, if the cylinder number returned is cylinder you swap the injector to - than you know the injector is bad. If the test returns the same cylinder as in the first test - then someting else is going on.

<small>[ October 31, 2003, 12:02 PM: Message edited by: twr ]</small>
 

SHOZ123

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I get the engine light that comes on and off while driving. My mileage has dropped about 3-4 mpg and if I pull the plugs the #4 plug is white whereas the rest are normal tan. If I pull the codes there is nothing there but I feel the #4 injector is not putting out the right amount of fuel.

Bottom line is look at the plugs, they should be light to dark tan. White is lean and black is rich or oil burning. If they are black and you can rub it off with your finger it is oil. If you have to scrape the black off it is too much fuel.
 

twr

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SHOZ123:
I get the engine light that comes on and off while driving. My mileage has dropped about 3-4 mpg and if I pull the plugs the #4 plug is white whereas the rest are normal tan. If I pull the codes there is nothing there but I feel the #4 injector is not putting out the right amount of fuel.

Bottom line is look at the plugs, they should be light to dark tan. White is lean and black is rich or oil burning. If they are black and you can rub it off with your finger it is oil. If you have to scrape the black off it is too much fuel.
Run the cylinder balance test as described by shotimes

"After the KOER test completes you can optionally run the SEFI or Cylinder Balance test. Race the throttle (it needs to go WOT) and release it. The computer elevates the idle to around 1800 RPM, and then will cut the injector to each cylinder looking for an expected drop in RPM. No drop means a problem with that cylinder. As each cylinder is taken offline, you won't see much movement in the tachometer, but the engine will feel rougher, out of balance. When the cylinder comes back online, the engine will feel normal again. A code of 1-6 identifies a cylinder found to be weak. A code of 9 means all OK. As with other tests, the codes are shown twice."
 

SHOZ123

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"Run the cylinder balance test as described by shotimes...."

I've done that and don't get any codes.
 

SHOZ123

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Last time I ran the codes I got one for the low speed fuel pump relay bad and one refrencing the baro sensor. The relay was bad and I put in a different CCRM. The baro senor is not functional at crusing speed AFAIK. But I still get the on and off ses at crusing speeds.
 

twr

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SHOZ123:
Last time I ran the codes I got one for the low speed fuel pump relay bad and one refrencing the baro sensor. The relay was bad and I put in a different CCRM. The baro senor is not functional at crusing speed AFAIK. But I still get the on and off ses at crusing speeds.
Paul,

Are you missing what I'm asking?? I asked if you got any codes after running the cylinder balance test or did you get the all clear code of 9 9?? (the only codes that can be returned after this test is 1 1, 2 2, 3 3, 4 4, 5 5, 6 6, or 9 9) If you got no codes after the cylinder balance test, then something isn't right with the PCM or the the test wasn't run properly. If you got a 9 9, then the PCM saw the rpm drop it expected when it cut each fuel injector.

<small>[ October 28, 2003, 10:57 AM: Message edited by: twr ]</small>
 

Dr.Evil

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I need to run this test, but cannot figure out how to tell it I want to run it. Is it in the code reader manual somewhere or what?
 

SHOZ123

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Are you missing what I'm asking?? I asked if you got any codes after running the cylinder balance test or did you get the all clear code of 9 9?? (the only codes that can be returned after this test is 1 1, 2 2, 3 3, 4 4, 5 5, 6 6, or 9 9) If you got no codes after the cylinder balance test, then something isn't right with the PCM or the the test wasn't run properly. If you got a 9 9, then the PCM saw the rpm drop it expected when it cut each fuel injector.
Sorry yes I did miss what you ask. Next time I have the car warmed up i will test the codes again.


Thanks
 

twr

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Dr.Evil:
I need to run this test, but cannot figure out how to tell it I want to run it. Is it in the code reader manual somewhere or what?
It's simple, after the last code is spit out in the KOER test, Goose the throttle (WOT) and let off. The engine idle will climb up to 1800rpm and you will feel it start to run rough and the even out - it will do this 6 times (6 cylinders)
 

SHOZ123

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Well my injector is firing as there is no miss-firing under any condition. The flow is not up to shuff I feel.
 

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