Engine shake and loss of power

[TetonLC]

Ok. So what I found was a loose wire to the injector on number two. This completely solved the misfire problem!

I have driven 500 miles so far today and no problems there.

My one lingering concern however is the lingering "slightly" rough idle. Before the problem it was buttery smooth. Now it's intermittently shaking at idle...

 

[OregonLC]

Ok. So what I found was a loose wire to the injector on number two. This completely solved the misfire problem!

I have driven 500 miles so far today and no problems there.

My one lingering concern however is the lingering "slightly" rough idle. Before the problem it was buttery smooth. Now it's intermittently shaking at idle...

Try pulling the battery cable for 30 min and see if an ECU reset will cure it. Could just need to relearn.

 

[TetonLC]

I'll give that a try tonight. Excuse my ignorance but how does the ecu relearn?

 

[OregonLC]

When you pull the battery cable it will clear the ECU's short-term trim memory. If it has 'learned' to cope with the faulty injector then clearing that learning could be helpful.

If every engine were 100% identical ECU's would not need to adapt. However, because of minor variances in manufacturing tolerances of engines and sensors (not to mention fuel, driving styles, and wear). This 'learning' is the ECU's way of normalizing these variables to achieve a 14.7:1 AFR, and therefore low emissions, across it's operating map.