Auxiliary Tachometer Lead/No Injector Pulse- 5.7L TBI

Joined
Jun 11, 2017
Messages
28
Long story short I had to have a rebuilt engine installed in my 5.7L Bravo TBI. After installing, my mechanic says he isn't getting fuel in the injectors. We have run a hundred tests (including shipping the ECM off to OBD diagnostics). We have replaced ignition control module (twice actually), throttle position sensor, distributor cap. It sparks and fires when you add starting fluid. The injectors have power, fuel pressure is at 13, tps sends signal back to ECM.

However, when hooking this up to a MEFI-1 scanning tool, we notice upon cranking there are no RPM's on the tach. We have tested ground wire after ground wire as well as all hookups. However when looking at the attached diagram, number 3 the auxiliary tachometer lead is just hanging loose. Is this supposed to connect into something?

Or any other ideas what might be causing no injector pulse?
 

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achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
... fuel pressure is at 13, ...

Should be 30psi... That would account for the injectors not squirting.

Also, can we have an engine serial number so we know we are looking at the right engine. Thanks.

That tacho lead hanging loose? It should be (hanging loose)... :D

Chris......
 
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