DME plug-in

[99hdtop]

Hello All, I sent my DME to get repaired, it has some cracked solder joints. The picture shows what I found on the plug that connects the unit. The ground wire has been tampered with. Some people have no business working on cars! I am going to solder the wires together and get rid of the splice. The ground wire is not usually that long is it? Is it ok to clean the DME plug with a contact cleaner before it is connected back to the DME? Thanks!

[Tippy]

I believe the ground goes all the way back to the intake lug.

Contact cleaner shouldn't hurt but you could use alcohol and swabs, probably milder if you're worried of damage.

[ischmitz]

This could be the version coding wires where someone snipped off the 2-pin connector. Only ohming out will tell for sure.

[Hunt3R]

I think that's the infamous brown "bridge-to-ground" wire that was for California emissions and non-Cali cars have it disconnected because it retards timing and leans the midrange fuel mixture. Mine was disconnected and taped back when I got my car, looks like it just came that way.

[JJ 911SC]

Originally Posted by Hunt3R

I think that's the infamous brown "bridge-to-ground" wire that was for California emissions and non-Cali cars have it disconnected because it retards timing and leans the midrange fuel mixture. Mine was disconnected and taped back when I got my car, looks like it just came that way.

You got it...

[99hdtop]

My guess then is that it is better not connected? Leaning the mixture too much can make it run at a higher temperature. Is that right?

[99hdtop]

Plugged in or not gentlemen? I sure would like to know.

[Hunt3R]

Generally its recommended to unplug it and tape it off, unless you have strict emissions testing where you live. As I mentioned, only California cars shipped with it connected, all others have the wire but its disconnected and taped off just in case its ever needed

[99hdtop]

Thank You!

[Quicksilver]

Originally Posted by 99hdtop

My guess then is that it is better not connected? Leaning the mixture too much can make it run at a higher temperature. Is that right?

IF that is the California emissions wire, connecting it to ground retards the ignition 4° to reduce NOx emissions. (can't remember if the 4° is across the range or in a certain subset.

Either way the "California wire" should be connected when you are headed to a sniff test.

[Quicksilver]

Check and see if that brown wire is #10. That is the CA wire. Fine to disconnect.

[99hdtop]

I have another question about this wire. My car is a RoW, made for the German market. Why would it have this wire?

[Hunt3R]

Perhaps like Wayne said you should first verify that wire is #10. Some German cars did come with emissions equipment though I don't know if they would've been equipped with the #10 bridge to ground.

[99hdtop]

Thank you. I will check the plug tomorrow

[99hdtop]

Checked the wire with a Fluke meter, it is #10 CA wire. I will leave it disconnected. Thanks all for the help. You guys are awesome!!!