ECM 3 ports or 2 ports?
 

So! A riddle:

A 2.4lt ECM has 3 ports, and a 2.2lt has ECM has 2 ports. What's the extra small blue port for and do I need it? Could I use this 2.2lt ECM on my 2007 HHR 2.4lt engine?

Thanks!

I don't know exactly what the connector is for, but there is obviously another harness that plugs in.

I wouldn't think that a different part number could work.

Guessing it has to do with the 2.4 having actuator solenoids and the 2.2 doesn't ?

Like I stated. Just taking a wild guess.

The ECM for the 2007 2.4L seems to be unique to that year.

2008 they both use the same part 2 connectors.ACDELCO 216140 {#12597125, 12612397}

2009 both use the same ECM, the one with 2 connectors. 2009 has VVT.

They are completely different for both in 2006.

There are several updated part numbers.

Those are the J connectors for the ECM, no you cant use a 2 connector ECM on a 3 connector car.

What is a "J connector"?

I think the question was the other way around.

The J connectors consist of the ECM pin numbers for the harness. Either way around it wont work. You must replace it with your ECM designated for your car.