Does anyone know how to test injectors?

 

i do.
its really easy if you have the equipment.
you have to have a fuel pressure tester you hook it up to the shrader valve (sorta like whats on the valve stem of your tires). you hook up a electrical tester to the injector your testing. you have a friend turn the key on, not starting the vehicle (be sure to remember that long story). then you note the pressure reading then you hit the switch on the injector peice to cause the injector to spray the fuel pressure should drop. then repeat for each injector connecting the tester to each injector one at a time. its really easy to do but difficult to explain when you can't show pictures of what your talking about.

 

Perfect. Can I get this tester at an auto parts store? I will call when one opens{-: Whats the presure supposed to be? I think I read somewhere that its 24.3 lb/hr? Sounds easy. Thanks {-:

<small>[ November 14, 2002, 09:08 AM: Message edited by: KLX300r ]</small>

 

I built a homemade injector tester which I
used a couple of times. It's got some
minor imperfections but it came in useful
for picking out the bad one of a set,
and selecting a junkyard injector out of
another pile to replace it.

Fuel supply: used a junkyard Ford fuel
pump and the piece of the fuel rail that
has the blowoff regulator, cut down so
only one injector "socket" is left. The
fuel blowoff and uptake are just fuel hose,
in and out of a 1 gallon can.

Power supply: a 12V set of battery cables.

Control: a LM556 timer, monostable mode
("one-shot" on one side to make a 5-sec
gate for a pulse train of about 2-4Hz,
roughly 10mS pulse width astable
on the other side. I just cobbled it up.
It's not calibrated or anything. The 556
output drives a power transistor to pop
the injector, supplied with 12V through
a junkyard harness injector connector.
Get about 18, narrow pulses out the injector.
Weakness: thermal stabilization / warmup
makes the first few test shots "throwaways".

Measure: a graduated cylinder, 10cc.

Injector mount: the fuel rail at top, a
hacked piece of aluminum angle stock to
hold the nose. And a cute little shelf
for the graduated cylinder below that.

Operation: Power up the pump. Press the
button. Injector does a series of squirts.
You are looking for two things: spray
pattern (consistent, clean, no drips)
and volume. Basically, after it warms up,
I record the gas volume of each one, repeat
2-3 times for accuracy. Anything that stands
out, is junk; uniformity is the key.

I assembled this all in a big suitcase deal,
one of those industrial ones. It's in the
shed somewhere. I've used it on a Lincoln
and a Porsche, and my neighbor on his Ford
truck. It'll tell you what you need to know.
Won't win any beauty prizes.

I've also used it to run Techron through the
injectors for extended periods off-car. But
it didn't fix the problem, which is Ford's
and Porsche's clever ideas of having the #1
injector at a dead end, so any sediment
collects on the injector inlet screen
instead of sweeping back to the tank.
and filter.

 

nice! I found one at Pepboys for $35.00. I think I'll try it first. I like the do it yourself approch but its a little easier to just buy a kit.
Thanks, It the store bought one doesn't work then I'll try your idea.

 

Well the tester that pep boys had was for testing the computer }-: It looks like I will be making my own tester in a box{-: lol Thanks for the info on how to do this. I found the LM556 timer at Radio Shack for $1.60 and already have a fuel pump and rail. I haven't seen the pin out of the switch but think I can figure it out. I'll let you know.
Thanks again <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" />

 

I bought the 556 switch and there was a wiring diag on the back. I understand the ground (lol) pin#7.
Is the power pin the one with Vcc pin#14?
Here is a list of the pin#'s and id.

pin#01 = Discharge
pin#02 = Threshold
pin#03 = Control voltage
pin#04 = Reset
pin#05 = Output
Pin#06 = Trigger
pin#07 = Ground {-:
pin#08 = Trigger
pin#09 = Output
pin#10 = Reset
pin#11 = Control
pin#12 = Threshold
pin#13 = Discharge
pin#14 = Vcc (?power?)

My question is what pins do I use and what for?
I have a little breadboard for the chip and wire for connections. I could always plug and test till I find the right combo but a little help would go a long way <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" />
Thanks in advance for any info.