Hanging ground straps?

[LD50]

I THINK these are ground straps anyway... steel braided type straps, I have one dangling near my steering res, connected to the body. I think that one is supposed to be attached to the exhaust shroud on the other side?

 

And I have this one (pic attached) hanging by my alternator, just noticed it recently, has an electrical type connector on the dangling end and also appears to be attached to the exhaust shroud.

 

Can you tell me where this one attaches? Is it safe to drive without one or both of these disconnected?

Edited March 29, 2007 by LD50

[unccpathfinder]

do u have headers...if so they used to go to the exhaust... i have broken straps all over the place on my truck and no issues so far

[LD50]

No, stock headers... i was curious about weather or not that one in the picture attaches to the alternator?

[mws]

That is a braided and bare copper ground strap, right?

 

The simple answer: Probably not, but try to reattach somewhere on the engine block.

 

The not so simple answer (Technophobes, RUN AWAY!)

 

There are a lot of what appear to be "redundant" ground straps on modern computerized automobiles to assure various devices all see as close to 0 volts as possible on their ground legs, and far more importantly, that all sensors see as close to the exact same voltage at ground as possible.

 

Nothing is ever exactly 0.00 volts except the ground plate in the battery. Everything before that is ever so slightly higher, due to the resistance in the conductors. The longer the path and the higher the resistivity of the path, the higher the "ground" voltage will be. If one component really close to the battery is seeing, say, 0.01 volts as ground, and another sees, say, 0.5 volts due to a long, high resistance ground path, things can start to malfunction due to sensors sending funky signals and currents flowing in abnormal ways. Maybe even frying transistors and other sensitive components. This is a very difficult problem to diagnose and repair.

 

The solution? Try to avoid it! Hence, lots of ground straps from various components to a common "reference ground". This reference ground will be close to 0.00 due to the big cable to battery terminal, but will never be exactly 0.00. That is acceptable as long as all sensors see the same voltage as ground. In my techno world, that is called the reference ground. Not truly 0.00 volts, but a common reference of say, 0.020 volts.

 

In the Pathy, the engine block is treated as the "reference" ground, and all sensitive electronics and sensors have the shortest possible and highest conducting ground paths to this common ground. Since copper has much less resistance than steel and the path is shorter, it causes less ground voltage variability than relying on the steel of the chassis as the ground conductor.

 

So, is it problem if one or two come loose? Maybe, maybe not. But it could lead to some funky glitches. I suspect the other end of strap you see there is connected near the transistor module to give it a nice reference ground. Those are not too cheap to replace, so I would try to reconnect it somewhere on the engine block to minimize risk of it stressing the transistor and causing premature failure.

 

And if a strap breaks or looks corroded, I replace it with a LARGER copper braid, solder the braid to the ring, clean the mounting surface, and seal up with dielectric grease to reduce resistance and risk of problems even more.

 

Most would call that overkill. But guess how many times I've been stranded on the side of the road for "phantom" electrical glitches and failures?

Edited March 29, 2007 by mws

[LD50]

Thanks for the reply. The strap in the picture IS connected to the block, it's the other end that I need to find a place for

[mws]

Oh.... sorry! Thought it was connected to body. So, try looking around up by the transistor module/coil. Bet you find an exposed terminal up there somewhere.!

Unfortunately, I have '88 so can't compare.

[LD50]

I found it!

 

However, when I grabbed the strap to re-attach it, the end connected to the block broke off pssd. Both straps seem to attach to arbitrary points on the body inside the engine bay and also to the exhaust shield.

 

So I guess now I have 2 ground straps to upgrade/replace. Something partsource would carry?

[mws]

Kinda arbitrary, but not really...

 

Send me the pieces and pm your mailing address and the strap fairies may just leave a surprise on your doorstep!

 

I'll pm my address to you... :type:

[LD50]

You da man! :bow: