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I'm getting a faint signal from the driver on the back of the pcm connector while running. My question is should it be alot brighter ? I can almost not see it flashing . Yes I am using an incandescent test light not an led. Could it be a poor ground feed to the ecm ? Thanks in advance
IMO, that sounds pretty typical of an incandescent test light on an injector control circuit with the engine running.
The problem is the injector pulse width. With the engine idling, then pulse width is likely to be less than 10ms. That's doesn't give the bulb in your test light enough time to reach full brightness, hence it appears dim. The fact that you're seeing any activity at all is a good sign for the ECM.
If you're looking for a more positive test, watch your test light with the engine cranking. Cranking injector pulse width can reach 40ms or more depending on ambient conditions. That'll give the test light bulb more time to light up.
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