Tom454

All I can find on testing the cold start injector relates to having it pressurized and checking the spray. Is there any "bench test" VOM data just to see if the coil is good? e.g.- ohms.

Cliff Harris

I got 5.1 ohms when I measured mine.

The spray pattern is not important because of the convoluted passages in the intake manifold and plenum that the fuel goes through.

aklim

Sure. You can check the ohms and know the coil is ok but does that tell you much? I sent a set of injectors to be tested. All ohmed out good but one was leaking. IT is hard to tell. I suggest you go give Jon at FIC a call.

Please call after noon today since I want him to have as few disturbances so he can get me the replacement for that bad injector that ohmed out just fine. I have a car down.

I really recommend AGAINST the ohm test. It is simple, cheap and really lacking in information about the rest of the injector which makes it misleading. After all, if you are sick, you really don't want your doctor to run a few tests, say "Take 2 aspirins and call me in the morning.", do you? Every injector I have sent for testing and tested myself at the local tech college after a few years of service has come out with reduced flow rates from gunk build up. The last batch of injectors, the mechanic noticed a slight roughness at the stop lights but ran just fine even with the bad injector.

aklim

If we look at that, wouldn't it be easier to start if it were as fine a mist as possible instead of a dribble? Sure, some of the emulsion falls out in the runners but isn't some mist better than less mist?

I think he also has Multecs so I would send the CSI off for cleaning and testing and toss the Multecs where they belong. In the trash bin.

Tom454

The ohms test will tell if the coil is shorted. I needed a number as a reference. Thanks for the ohmage.

Cliff Harris

The injector resistance test only reliably tests those injectors that flow the fuel around the injector coil to cool it. The ethanol in today's fuels dissolves the wire insulation coating and that's when they short out.

My opinion is that an inductance test is a much more valid test, but then few people have an inductance meter (I do).

Tom454

Have several (digital) Capacitance checkers but no induction meter. I got 5.1 ohms as well on the injector coil, but the test leads were 1.3 which gives me a final value of 3.8 ohms. The switch measured 33 ohms. I'm going to guess neither are shorted or open and go ahead and install them.

aklim

I tossed an injector in the trash. Ohm test was fine with the others. It didn't hold pressure. I can blow through it. Other 7 and the new one had the same resistance and you couldn't blow through it. Only definitive answer is a bench test. The rest is somewhat misleading

Tom454

I agree that the flow test is the best & correct way to do it.... but you need to pressurize it to flow test it. If the engine is apart, that test will have to wait. My engine is apart, I cannot pressure test. So in the mean time, the resistance test told me that the injector electronics look good and I don't have to source another injector before I start to assemble the engine. Once I have a fuel rail and a fuel pump in service, I can hook the injector up & flow test it.

Call the resistance test a "pre-test" if you want. It only takes a few seconds and then you won't waste time setting up the real test. This was the purpose of my original question. I needed to know what to expect in Ohms.

aklim

If it is a common injector, FIC may have a few they can send you while you send in your cores or if it doesn't matter, send them to FIC for cleaning and testing so you know if it is definitely right

Tom454

It has a funky mounting arrangement:

aklim

Give Jon a call. Maybe he can walk you through removing the pipe for easier shipping or maybe not. I never had one so not sure but they can clean and test them for you.

Alternatively, you can seal it up and change your programming to spray more fuel, so I have been told.