92 Vette Injector Troubles

[Joe Rappa]

I got called to a local shop today that had a 92 Vette No Start. Good spark. No Inj pulse with a noid light, but when checking with a lab scope it showed a normal injector pattern, except that the pulse width was around 2mS when cranking. That looked way too short to me.
I grabbed my low amp probe to check the injector amps. These are gang fired, so I checked them all individually at each injector. All were 2 amps except #5. that one was 18 amps. Kinda cool. Thought I's share it.
First one is Inj #5.
Joe

[Witsend]

So when you disconnected injector #5 drawing 18 amps , then the rest of the injectors got more current and engine started and ran minus cylinder 5?

[Joe Rappa]

So when you disconnected injector #5 drawing 18 amps , then the rest of the injectors got more current and engine started and ran minus cylinder 5?

That is exactly what happened. I haven't seen that since around 1995 or so. Definitely not a common failure, and only possible on gang fired injectors.

Joe

[diesel71]

that's great information, nice to see the screen shots helps me learn what to look for