3900 V6 LZG E38 or E67?

[NateD4]

Does anyone know if a 2008 Impala 3900 V6 LZG uses the E67 or E38. So far GM lists the 12612384 a the correct ECM which is an E38. However this engine has DOD and VVT. An article I found says it uses an E67. However the harness has a third blue connector that would appear to be for an E67. I have a hard time believing that GM's listing is wrong (that it is indeed an E38). However what is this extra blue plastic harness connector for? Is there another module that plugs into it?

Unfortunately I don't have the donor car or any decent pictures from it.

[Taz]

As a disclaimer ... I am not a V6 expert ...

It seems GM used both the E38 and the E67 on that platform during 2006 to 2009. In 2010 (or late 2009) it seems some of the vehicles using that platform switched to the E37 ECM.

For a 2008:

2 engine harness connectors (black & grey) = E38
3 engine harness connectors (black, grey, & blue) = E67

The engine harness connectors are all black coloured on their outer shell, with a coloured insert (as seen from the under side).

This platform would have also used a T42 TCM - the connector for this has a blue coloured outer shell. I mention this as the ECM / TCM combination are usually mounted in the vehicle in close proximity - and therefore if just looking at a powertrain control wiring harness in isolation, some may confuse the TCM connector as an ECM connector - as these are close together on the wiring harness "trunk".


Regards,
Taz

[NateD4]

Taz,


Thanks for the quick reply. I'm a bit confused as all the E67 pictures I've seen the third (middle) connector is blue in color on the ECM. Do you know which connector it uses so I could attempt to verify the connector is correct for the E67 compared to a T42.

This would help eliminate the confusion.

Oddly I had the dealer look up the engine vin from the engine and the ECM I have (they are off two different VIN cars of the same year and engine type). Both cases list the E38. However this article: http://www.gminsidenews.com/forums/f12/gm-announces-240-hp-3900-engine-2526/

Seems to state the E67 was used.

The real issue I suppose is to match up the blue connector to the right control module (is it to an E67 or a T42). Here is what I perceived to be a fairly comprehensive list of GM connectors: http://www.eficonnection.com/eficonnection/ConnectorSearch.aspx

If I an figure out how to upload a picture I'll see if I can get a picture of the connector.

The last issue I have is how to wire up the cruise control. My 87 car had a vacuum cruise actuator. The question is if I need a BCM or TCM to control the cruise (6 speed manual install).

Any ideas?

[Taz]

Sorry ... thought I had described the wiring harness connectors sufficiently well in post #2. Post a picture of your wiring harness ECM / TCM connectors and I should be able to tell you what they are from. I am very familiar with EFI Connection's site - however that link is of little assistance in determining what ECM / TCM your wiring harness is from.

As for your other questions:

1. Cruise control is typically a BCM function in Gen IV controllers.

2. Manual transmissions do not use a TCM.


Regards,
Taz

[NateD4]

Looks like it is a T42 controller. The pictures I found helped narrow it down.

The new question is whether I should look into the extra IO of an E67. The question it then forces me to ask is does anyone have the IO mapped to it at all?