It's using the stock TBI distributor that was in the Blazer.
It's using the stock TBI distributor that was in the Blazer.
I'd download Tuner Pro along with the correct ADX for your application and use that.
WinALDL seems to be hit or miss as far as getting good data.
And do you mean 1227747?
Do you have spark?
Does the fuel pump prime, and does it turn back on when cranking with the OPSU (Oil pressure Sending Unit) unplugged?
The man who says something is impossible, is usually interrupted by the man doing it.
Haha...Oops yes. I have Tuner Pro RT, and it's not pulling any data either.
I have spark (it will run when spraying carb cleaner)
All relays kick on (fuel pump runs while cranking) - I have not tried with the OPSU unplugged
Noid light on the injector harness indicates no signal from ECM
Replaced Ignition module
Traced every wire (found some issues and corrected)
Tested all voltages and resistance through the wires
This is why I was hoping to scan the computer to see what signal I could be missing, but I can't seem to get any of them to work. I'm starting to wonder if the ECM could be bad?
Last edited by mjensen; 03-19-2017 at 07:08 PM.
There are two wires going to each injector. The white and red wires should have 12V all the time when the ignition is on. Can you confirm this? The ECM creates the pulse by providing a ground (blue and green wires) to the injector.
lf you unplug the injector and put a nine volt battery across both terminals, you should hear it click. If you try this, only do it for a fraction of a second.
Last edited by mmigacz; 03-19-2017 at 09:56 PM.
1986 ski centurion boat, 351W, gt40P heads, edelbrock performer rpm, 1227747 ecm, 72 lb/hr injectors (@18 PSI fuel pressure), .490/.490 lift, intake 278 duration, exhuast 282 duration, 112 lobe separation
1969 camaro, 355ci, performer RPM intake, camel hump heads, 1227747 ecm, 454 throttle body (@18 PSI fuel pressure),
2016 Chevy Cruz
2014 Chevy Silverado
I have verified that they have 12v and the injectors do click with a 9v battery. I've checked the resistance in the injectors, as well as the wires running to the injectors, and they are well within spec.
Dumb question, but have you verified fuel is actually getting up to the injectors?
Don't force it, get a bigger hammer!
I have, and we've got fuel. I'm fairly certain that the computer is just not receiving SOMETHING that it needs in order to tell the injector circuit to ground.
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