Can a 194 bulb be used to see if a fuel injector is pulsing

[greaseyfingers]

I read, before, that a 194 bulb can be used, if you don't have a noid light, to see if a fuel injector is receiving a pulsing signal by inserting the 194 bulb wires into the fuel injector's connector.

I didn't have a 194 bulb handy.

So, I used a 161 bulb, instead, and didn't detect any flickering pulse signal at the fuel injector's connector.

My 1987 Ranger, 2.9 engine, isn't firing on it's number 3 cylinder.

The compression is 160 lbs. on this cylinder.

I've changed the ignition coil, spark plug wire, spark plug, computer, computer relay, fuel pump relay, coolant temperature sensor, map sensor, air charge sensor, different distributor and ignition module.

I've cleaned the ground connections.

I've, also, taken apart and cleaned all the electrical plug connections on the fire walls.

Both wires on the fuel injector's connector have power to them, when I checked it with a coninuity light.

What else would be left to check, that would causing a fuel injector not to be receiving a pulsing signal for firing it?

 

[mp3deviant721]

Bad fuel injector?

 

[greaseyfingers]

Bad fuel injector?

The fuel injector tested out to be 15 ohms, which I think is within specifications.

I didn't receive a pulsing signal at the fuel injector's connector, using a 161 test bulb, as already mentioned, being I'd read a 194 bulb could be used for doing this, if a person didn't have a noid light to do this procedure.

That's why I'm wondering if using a 161 bulb will work for doing this, instead of a 194 bulb, as they're the same size in appearance?

 

[TheTopher]

You should be able to just crank the engine over a few times then pull the spark plug. if it's soaked in fuel then you've got a spark problem, if it's not then you have a fuel issue.


You can also hook the spark plug into the boot and hold it against the block while cranking the engine to check for spark. MAKE SURE YOU DON'T HOLD IT NEAR THE OPEN SPARK PLUG PORT WHILE YOU DO THIS!

 

[Ranger Dave (B25)]

You can also hook the spark plug into the boot and hold it against the block while cranking the engine to check for spark. MAKE SURE YOU DON'T HOLD IT NEAR THE OPEN SPARK PLUG PORT WHILE YOU DO THIS!

...unless you like the smell of burning finger hair...

 

[TheTopher]

...unless you like the smell of burning finger hair...

haven't had that one happen yet, but I also don't have any hair on my fingers.

 

[greaseyfingers]

You should be able to just crank the engine over a few times then pull the spark plug. if it's soaked in fuel then you've got a spark problem, if it's not then you have a fuel issue.


You can also hook the spark plug into the boot and hold it against the block while cranking the engine to check for spark. MAKE SURE YOU DON'T HOLD IT NEAR THE OPEN SPARK PLUG PORT WHILE YOU DO THIS!

It's got good spark going to that cylinder.

That's why I'm wanting to check if that fuel injector is receiving a pulsing signal, at the connector, to determine if that is the problem, or if the fuel injector might be plugged, if it was determined that the fuel injector was receiving a pulsing signal.

That's why I'm wondering if a 194 bulb can be used for doing this test, like I read before that it could.

Even though I used a 161 bulb, instead, as they're both the same size and I happened to have one laying around.

So, I thought I'd try it.

However, it's not detecting a pulsing signal at the fuel injector's connector.

 

[ashleyroachclip]

I believe you are looking for a ground signal to that injector, as that is all the computer supplies

I also believe these engines are batch fire , so several fire at the same time
I doubt you can see the flickering as the process is very fast.
Replace the injector from another cylinder that you know is firing, if it works you know what the problem is.

 

[TheTopher]

Replace the injector from another cylinder that you know is firing, if it works you know what the problem is.

*facepalm* yea', I forgot that one.

 

[Sasquatch_Ryda]

They taught us in school that a 194 bulb can be used in place of a noid light. I've done it and it does work.

 

[greaseyfingers]

They taught us in school that a 194 bulb can be used in place of a noid light. I've done it and it does work.

Will a 161 bulb work, too, for detecting a pulse signal at the fuel injector's connector, being it's the same size in appearance as a 194 bulb?

When I used a 161 bulb, being I didn't have a 194 to use on the fuel injector's connector.

It lights up, but doesn't flicker at all.

So, would that indicate the fuel injector's connector isn't receiving a pulse signal?

Or, does 194 bulb need to be used, instead, for doing this test procedure, because maybe a 161 bulb isn't able to detect a pulsing signal, for whatever reason?

If the fuel injector's connector is receiving a pulse signal.

The light bulb being used for detecting the pulse signal, should flicker, shouldn't it?

 

[Sasquatch_Ryda]

Not too sure if the bulb makes a difference...we were just always told a 194 would work.

You should have 2 handy....your license plate light bulbs...

Also if your light was staying on constant then that injector is not receiving a ground pulse for the PCM.