Found a loose ground
Thread Starter
Intermediate
Joined: Oct 2010
Posts: 41
Likes: 0
From: Duluth Ga
Found a loose ground
I have a 90' and I found a ground just hanging yesterday. It looks like a flat shoe lace and its connects to the passenger side nut on the master cylinder. The other end of it lost its crimped connector and I have no idea where it goes. Doesn't seem long enough to mount to the head anywhere. Any help would be appreciated. Thanks guys
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Thats probably been moved from the original location. Thats the ground strap that runs across the frame to block somewhere down around the oil filter/bell housing area where the harness ground collection is bolted. Its common for people to see this strap and believe they have found the "main" ground for the car, but its only a bridge between block and frame. This one may have been added. Because grounds are the arteries of the electrical system on these plastic cars, each is important and each has a specific job. I added 2 battery cables to mine, battery to block and battery to frame, and spliced in a new ground wire battery to harness ground (same G104 bundle).
The master cyl isn't the best place for a ground but its easy. If it were me, I'd look at the frame and find a bolt there that can be pulled and attach the strap there to a clean spot and then the other end to its bolt on the block. Your other end should be around the filter somewhere. You'll have to search from below.
The master cyl isn't the best place for a ground but its easy. If it were me, I'd look at the frame and find a bolt there that can be pulled and attach the strap there to a clean spot and then the other end to its bolt on the block. Your other end should be around the filter somewhere. You'll have to search from below.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
It's the stock ground between the block (in front of the filter) to the driver's side frame. Look carefully and you will see a bolt hole. It should not be attached to the master cylinder bolt.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
There is a short 1/2-20 bolt on the back of the block over the oil temp sensor, it goes there.
I actually replaced mine with a battery ground cable that goes to the frame, then I run a second battery ground cable up to the battery ground.
I actually replaced mine with a battery ground cable that goes to the frame, then I run a second battery ground cable up to the battery ground.
Team Owner
Joined: Aug 2005
Posts: 34,988
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
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I think the one the OP refers to is the one that connects from the frame to the bellhousing.
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Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
There is a connector on the master cylinder that warns you if you have a pressure difference between the front and rear brake circuits. I somehow managed to break mine and spent a LOT of time finding another (they stopped making the connector several years ago). This connector has a black wire with a white stripe.
There shouldn't be any other wiring connected to the master cylinder. It doesn't belong there, which implies that it should go somewhere else or it was added for some reason.
There shouldn't be any other wiring connected to the master cylinder. It doesn't belong there, which implies that it should go somewhere else or it was added for some reason.
