Ground wire issue?

[Jason]

Hi All,

It's been a little while since I've been on here but I have ran into something I have another question about. Last year after I bought my Aurora I brought it in for a general in depth check up/diagnostic. One of the things they pointed out I should get to when I can, is a broken transmission ground (I believe thats what they said - could be way off lol). Im including some images below, in the hopes someone might clarify what this is exactly, and if it's safe to ground to and any (good) ground point I find or make, if that's whats needed.

I've also included a couple pictures from the date I purchased the car, to compare to what the engine bay looks like now for any potential skeptic Aurora owners - a little TLC goes a long way!

Before (when first purchased):





Another before:




After (I've also drawn an arrow to show where the wire question is stemming from below):



When Looking just underneath the upper radiator hose (pointing to the wire):





A closer look:



And last but certainly not least, from under the front of the car:








You guys haven't failed me yet, hopefully we can keep this success rolling
Thank you!

[aphex]

Unless there is a 2nd ground to the tranny, it appears they left the severed end of the ground outside of the plastic cover. I'm going off of the last picture in the series, from under the front of the car. Seems the ground is the (maybe 15mm?) bolt centered in the picture? I'd follow the wiring to locate the other end of this ground. I'd make sure to remove the negative to the battery before starting in on removing and replacing the ground wire. With the location you could probably get to it from the top of the car but you might need to drain the rad and remove the hoses.

[Jason]

Thanks Apex! 

I'll see what I can do about following the ground to the source. I haven't gotten in there enough to know the difficulty, but I do know from just looking and feeling around that the plastic tubing the ground (assuming it is a ground) is sticking out of is stiff and hard to manipulate. 

I am not sure if it's related or not, but my car when running tends to sit around 14.6 - 14.8V on the DIC occasionally going up to (but never over 15V). And from what I can tell, pressing the gas or releasing it seems to have a small effect on the voltage readout. That along with occasional hard starts or a small funny noise every now and again leans me towards this being a ground of some sort. 

If it is a ground, does it matter where its grounded to? I'm decent with electrical and wiring from experience (sounds systems etc), but dont know much about possible engine related grounding.

[aphex]

I don't see the difference in where you ground on the frame. Does that plastic wire cover go straight up and behind the air filter box?

[Jason]

It does look like the tubing comes up behind the air filter box to a few split offs

[aphex]

Personally, I'd want to open up the plastic tubing to make sure it is indeed that ground before trying to remove and replace. If it is indeed that ground wire & I was not able to find the other end by following the wire - then I'd personally try repairing the wire using an electric tubing connector and a torch lighter, not just replace it with another ground. I wouldn't feel comfortable doing that unless verified that it is only a direct ground from the trans to the body.

If that was the case (direct grounding for trans) I'd try to wire it to the same spot and zip tie it to the tubing if unable to place inside that tubing. In theory I would feel fine grounding anywhere on the frame, but I try to fix and replace things as they are.. Except I've got some grounding modification going from the alternator as shown on the how to, and I'm going to do the grounding mods which is another thread or two.

Edit: If it is the ground and you're trying to repair it at the break, but the wiring is too short, then you can add a little more wire and use 2 connectors to bridge.

[sempar]

I don't see any ground wire that goes to the 4T65E transmission. There is two ground wires that go to the front driver side of the engine. G100 is the ground for the PCM, AC, and the auto trans. Can't be that one since the car apparently runs fine. G102 is the other ground that is used for the air injection pump, and I bet that's the one that's broken. G100 is bolted to the lower case of the engine, right by the trans case. G102 is bolted directly above it, that's where your broken ground should go.

John

[Jason]

Sempar,

I'm almost afraid to jynx it but I want to say thanks ahead of time lol. The only CWL I ever get it for my secondary air pump - the fuse keeps blowing after a while of driving so I replace, reset and it's gone for a while till it blows again. I wasn't even thinking of that because it was a problem for another day I just passed emissions 😁
I will try to see if I can verify it's the issue soon