Ground wire info?

[bogle]

Consider this pic



My car does not have “ground wire B” (bottom right). It looks like it connects to the gusset that the fuel pump resistor is bolted to, then somewhere on the engine. I have 2 questions:

- what is the part number of this ground wire? I’d love to order one
- where does it connect on the engine? Any pics?

 

[Old Guy]

On my 2000, ground wire B connects from the left side of the front head to a special connection in the middle of the firewall that is approximately 5-7 cm below where the targa brace bolts to the firewall. Check for damaged strands where it bolts to the head because that is where all the flexing due to engine vibration occurs and where it gets maximum heat exposure.

I think it is part #19; but, really hard to tell from the parts diagram.

Wire Harness for 2000 Acura NSX | OEM Parts Online

acura.oempartsonline.com

 

[Wild Turkey]

Agree it is 32620SL0003, "CABLE, ENGINE EARTH"
On my 1995, here is a picture of the mounting on the firewall, post #23, by me when I was wondering how remove it. It does NOT attach to the gusset.

What is this?

2022/Feb/24 - New question added about a bracket in front of the headlight retractor. 2021/Sep/7 - Part #3 that I can't identify Do we have a what is this thread? I couldn't search for it since what is and this are too common. Took my rear bulkhead off to fix broken tabs and found this. Anyone...

www.nsxprime.com

 

[Wild Turkey]

Here's a picture of the other (engine) end on my 1995. It connects to the left side bolt for the front cam cover by cylinder 6. I hope that's correct. I'm surprised it doesn't bolt directly to the block, but I guess the bolt into the cam cover connects well enough electrically to the head.

 

[bogle]

Thanks both of you and interesting that it is the center ground. My car does have that one. I was thrown off by the detail pic where it shows one side of the ground wire mounting under the alternator.

There is a nutsert there where the detail pic in the manual shows. I ran my own ground to the motor a while back, but wanted to use an oem ground if possible.



Do you guys have anything connected to that area?

 

[Honcho]

Thanks both of you and interesting that it is the center ground. My car does have that one. I was thrown off by the detail pic where it shows one side of the ground wire mounting under the alternator.

There is a nutsert there where the detail pic in the manual shows. I ran my own ground to the motor a while back, but wanted to use an oem ground if possible.

View attachment 181029

Do you guys have anything connected to that area?

What year is your NSX? They changed some of the engine bay ground locations during the first couple years.

 

[bogle]

It’s a 91

 

[Honcho]

It’s a 91

On the early 91's they ran an engine ground from the alternator bracket to that ground point on the gusset. But then they deleted it at some point in the 91 production run. On my 92, that ground point still exists, but is painted over and is used to fix the main engine harness to the car.

 

[bogle]

Ok great to know! I will not worry about it then

 

[Old Guy]

My 'head' ground is on the same cam cover retaining stud as tturksta's. My 2000 also has the nutsert and locating hole in that forward gusset and like Honcho says, it is used for a retaining clamp that supports the great big wire harness which runs up the right side of the engine and then bends over to cross the front cam cover.

 

[Wild Turkey]

I guess the takeaway is not to look at other NSX's, but consult the (appropriate year) service manual.

 

[Old Guy]

I guess the takeaway is not to look at other NSX's, but consult the (appropriate year) service manual.

Consulting the age appropriate service manual is always good advice. However, particularly in the electrical section, some of the service manual location drawings leave a fair amount open to interpretation. In addition, for whatever reason the electrical section of the SM seems to have more discrepancies / errors and it is always good to have an Electrical Trouble Shooting manual which seems to be more accurate when it comes to electrical stuff. The ETM also has the great advantage that it has real labeled photos of every connector / wire on the car rather than those line drawings in the service manual.

That said, since the ETM did not show up until 1992 and since Bogle appears to have an early production 1991 the ETM may also be inaccurate and looking at another early production 1991 might be the only way to confirm stuff.

It does reenforce the fact that when people ask for advice on matters they really need to provide the year of the car as the absolute minimum detail.