When testing my injectors, I get one with NO resistance reading. ?? yes all other 5 show the ohms , but one shows nothing. Tried it different ways. Any one know what is going on. The injector still clicks when the engine starts and though the idle is rough, the engine smooths out over 1500 rpm.

 

You just put the meter on both of the leads. Should read 11.8-12.

I've never had one read as high as 12. Maybe the battery in your meter is dead? Or all your injectors are bad.

 

Could just be a dead injector, If you have a VG, pull the spark plug lead on that cylinder with the engine running, if you don't notice a difference to the idle, then the injector is probably dead. If you have a VE, you could just pull the injector connector instead.

 

no resistance is either a totally failed injector, or you didn't test it right.
resistance is supposed to be between 11 and 14 ohms.

 

"Shows nothing" as in 0 Ohms or "nothing" as in the meter doesn't do anything? If it's the latter, clean the pins on the injector... get out you precision scredriver set and scrape the corrosion away and try again. The harness connector might make contact since it's been there for a while, but it's hard to get a test from caked pins.

Depending on which engine and which injector, you could easily test from another point down the line at another connector to double check.

Hope that wasn't too obvious.

 

Shows "nothing". The pins are absolutely clean. Also there is nothing wrong with the meter as I can just move over to the next injector and I get a proper reading. Its injector number 6. Someone told me the coil may be shorted ?? However the injector clicks when the engine is running. the engine runs rough at idle but smooth over 1500 rpm ?? any one with ideas ?

 

Replace the injector...It's toast.

 

The part I am curious about is how the engine runs smoothly (over 1500 rpm) with one injector being toast ?

 

who knows,injectors can act funny sometimes..

But if you are reading 0 ohms,chances are the injector is bad.

 

The DVM i have will read nothing too when the resistance reading is out of range of the selected range the DVM is set on (i.e. if resistance is 200M-ohm+ and DVM is set on 20-100Ohm, display will be all 0's or blank... can't remember which)

 

It may appear to run smooth, but it is more likely the rough feeling is less noticable at higher RPM. How are you checking the 'clicking' from the injector? If you unplug it does the clicking stop?

If the coil is shorted you will read zero ohms, not infinite. But it will have the same effect on the engine.

As mentioned earlier, with the engine running, pull the plug lead for that cylinder, if you don't notice any change in how the engine is running, and you don't get any meter reading on the injector, then I would say 99% chance you have a dead injector.

 

Another "trick" to check whether the injector is clicking when running. Start your engine and let it idle. Take a long flathead screwdriver (I use an 18inch Craftsman), hold the flathead against the plastic part of the injector. Then hold you ear against the top of the handle. You should hear the injector clicking at a regular interval. You should also be able to feel the vibration of the injector opening and closing. If you do not hear the clicking, your injector is not functioning.

 

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That is exactly how I check the injectors to see if they are clicking. it lets you get to all 6 , including the one under the intake.

 

Yeah, but you better have a good ear. I had to go back and listen a couple of times to realize that enough noise comes back from the other injectors... or at least from one ajoining.

 

If the meter leads were making bad contact with the injector pins he would have gotten a very high resistance or infinity. 0 Ohms means he had excellent contac...or his meter leads were touching each other. I just measured 3 of mine (front) and they all read 0 Ohms. Me thinks my injectors are bad.

 

its dead... i have 3 with no resistance