no injector pulse please help!

[jaykilla116]

91 cb7 car wont start.
if you spray starter fluid in intake it starts then dies. therfore the ignition can be ruled out its a fuel issue. i tested the main relay and it past i test the harness it past i even tried the resitor box and it passed spec were from all data. i starting to think its the ecu . but before i go get one is there somthing i might be over looking?
is there a way i can check the plugs that go to the injectors ?
any specific grounds i should check?

[accordztech]

you missed the main point...

what turns on the injectors and fires the coil?

Check distribitor coil
check ignition control module.

Its seems you have access to info, so measure the resistance per FSM and you will find your issue.

[nine_deuce]

Could be your injectors, too. I had this problem when I did my h22 swap. My car wouldn't fire on it's own, checked the injectors, they were dead. We sprayed starter fluid in the throttle body, it'd start and run until the starter fluid was gone. Checked voltage at the injector plugs, resistor box, even hooked an injector directly to the battery (had an old injector plug) didn't do anything. Put in some different injectors, worked perfect.

[accordztech]

...forgot to ask, you getting a spark?

[wed3k]

...forgot to ask, you getting a spark?

if it runs on starter fluid, it rules ignition out

[accordztech]

if it runs on starter fluid, it rules ignition out

blah, shit lol. DUHHH!

Check to see if your injectors are getting a pulse.

[jaykilla116]

I got a new ecu this moring ruled that out ..... Ok and the dizzy has to do with the injector?

[accordztech]

Check to see if your injectors are getting a pulse.

check with a test light

[toycar]

Test light will not show neg pulse.

Use a multi meter and measure voltage, you will see thr minus sign indicating neg pulse if the injector is getting it


Also, starting fluid can combust from compression alone, so that's not always a sure shot way to rule out spark.

Pull a plug wire and insert a screwdriver where spark plug attaches. DON'T TOUCH THE METAL. Hold the screwdriver by the handle, and bring the shaft of the screwdriver against your valve cover to provoke the spark to arc. You will see the spark if you have it.

It's very obvious, and completely safe as long as you don't touch the metal shaft. This is a very easy way to check for spark if you do not have adequate tools.

[accordztech]

Test light will not show neg pulse.

Umm, yes it will. If you know how to use it.

[wed3k]

Umm, yes it will. If you know how to use it.

agreed, used it many times but i think on my vw, i needed a led test light because it is batch fired.

[toycar]

How's that work with no voltage?

We are talking about checking neg pulse from ecu right? There's no voltage associated with that.

Does an led test light still flicker to that?

If so, I feel like an idiot.

[wed3k]

ummm, test lead clip on positive, ecu grounds the injector.

[accordztech]

ummm, test lead clip on positive, ecu grounds the injector.

[toycar]

ummm, test lead clip on positive, ecu grounds the injector.

I know that, I'm saying with no voltage associated with the pulse, how does the test light get power.

Im talking about the initial neg pulse that the ecu sends after you turn the key to the on position, before you try and start the car.

Are you saying with the car cranking over this works?

I get that. I was under the impression we were talking about the initial neg pulse, and there is no voltage on the circuit in that scenario.

If that is what you are talking about, the initial pulse, then educate me on how the test light gets power.

That's the part I don't understand. I know how to use a test light.