Can someone who has a G320 check to see if they have the connection on the left? 

 I think the connection on the left will fit the older version sensors? See second attached photo.

 The wiring diagram for the G320 shows 2 wires going to the sensor...green(gn) and brown/white strip(br/ws).  The wire colors of my new connection is green/white stripe(gn/ws) and brown/white stripe(br/ws). Do you think it will still work?

 DO you think my new harness was made wrong (or updated with new type connection) ? ...or do you think I can substitute a temp sensor that will fit new connection.  It sure seems like the old connection is more 'durable and heavy duty', but what the heck do I know.

 Lastly, if anyone has installed a harness, what is the (last) connection that goes to the left rear of the motor below the oil filter ?

Thanks for any help and insight you can provide.

 Mike

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A little more info with the attached EPC image.  Everything on the harness is accounted for except as noted.  It looks like I can just get the intake air temp sensor that fits the different connector and of which seems to be used on later model vehicles.  I just cant figure out what #17 on the EPC screenshot goes to....at least until I pull the side of the motor down to get to it.

 Thoughts welcomed.

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The new sensor looks exactly like what came on the OM606.  My guess would be that the same sensor used on most MB engines of that era.

How about measuring the room temperature resistance of your existing sensor.  I can measure the same for mine.  If they are the same then you could replace the sensor or use the old one with a connector swap.  If they differ, you are stuck switching connectors.   I can see why they dropped the old style.  There is no reason to use a coax connector and cable for this purpose.  It costs more and provides no benefit.

 Thanks Alan.  I will check out.  I looked at the EPC for the harness that applies to the later G320 after VIN 999XX and they show the new connector on the diagram and it is labeled as such being the IAT...still has the coax type for the CPS and other connectors though.

 I just thought it was weird for the new harness to have all the coax type connectors to match the old one except for this one connection.

 Perfect. Thanks Roly.  Great to know about the IAT being same.  I just hope the connection is wired for that purpose and that the labeling on the EPC diagram is a mistake for that connection #17 which should go to CPS.

 I should have known it was the crankshaft position center under the oil filter.  

 Mike

The MAF is at the intake, but the IAT has to be measured post intercooler.   So they have to have two sensors.

Temperature is tested just before the intake runners.  Happy?

Harness replacement complete.  I have attached a photo of how the wiring looked on the old biodegradable harness which was prevalent throughout all areas. I also attached photo showing the previously unidentified connections with there true identity.

Engine starts and everything appears to be happy, I will feel a lot better in my travels knowing that crappy wiring is history.   Not really a fun job as on this model year the harness had to go through firewall to its connection behind fuse panel above passenger feets. 

Mike

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Looks like both should work along with A6511530028

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Well, they are on my "watch list" as I am catching up on the maintenance items.  I have not looked at either up close and have not experienced any symptoms or gremlins pointing me that way as of yet.

Thanks for the "head-up" though.

Mike

The ETA, part# A000 141 57 25, is shared with the M104 powered W124 chassis cars without ASR.  I took a glance at the green label on the ETA on my G320 which shows the build date of the ETA to be June 1996....funny, as my G was built in October 1994.  I hope they/someone did not replace a crappy ETA with a less crappy ETA.

I thought the good ETAs and/or rebuilds started at 1998...I have also read where some believe 1996.  I guess only way to find out is close inspection of the wires themselves in the loom or opening up the side of the ETA and see what it looks like inside.  I will keep my eyes open for a more recent build unit for a backup...that is, casually look.

Mike

A 1996 ETA is going to be in the danger zone of the bad wiring era -- it may or may not be bad wiring. Generally anything done after 1998 or 1999 will be definitely safe. Hopefully yours is OK, but the date puts it in the suspect zone. The good thing is that non-ASR ETAs for the M104 are very common in wrecking yards, and often have been replaced over the years, so it is probably not difficult to find a used one (or one via eBay) that was made in 1999 or later.

Here are a couple of sets of photos from my M104 top-end rebuild of what bad/biodegradeable wiring looks like INSIDE of an ETA:

http://www.500eboard.com/forums/showthread.php?5082-HOW-TO-M104-W124-Top-End-Rebuild&p=57830&viewfull=1#post57830

And bad wiring inside the ETA's cable (I slit it open with a razor blade):

http://www.500eboard.com/forums/showthread.php?5082-HOW-TO-M104-W124-Top-End-Rebuild&p=58868&viewfull=1#post58868