I have a SN95 and recently got in my car and noticed a constant ticking noise coming through the speakers. After researching for a week or so I have only came up with the possibility that it could be a ground issue. The only problem I have is finding the ground cable that goes from the body to the motor mount. Does anyone have a picture of it? Does this sound like the issue?

 

two things, you may have bad spark plug wires, try replacing them, or a bad alt........when a diode goes bad ac current can backfeed into the system and cause such. First I'd try replacing the wires, my 92 used to make a whiring sound in the speakers when the suppresion core around the wiring was bad

 

Thanks, I bought new plug wires yesterday. I will put them on Sunday and see if that fixes it.

 

SN95 do have grounding issues. Sorry I do not have diagrams, they are on my other computer. It sounds like to me Mjr46 hit the right area to trouble shoot though Ignition/Alternator.

Grounding issues, you will see in some cases a higher reading on some of your Factory gages. I took my Fluke and verified all of my grounds. It does make a big difference. Over time the conductor to lug corrodes and causes higher resistance. Also the contact between the lug and painted body panel. Our mustangs are getting older and this is often overlooked.

 

A quick way to test a ground is to use a volt/multi-meter to do a voltage drop test.

• Key On, Engine Off
• Set your meter to as close to 15 volts as possible without going under.
• Touch the negative meter lead to the negative battery post
• Touch the positive meter lead to the ground connection/lug/wire you want to test.

You should get within 0.001 & 0.5 volts DC. If you get any more then that, then there is excessive resistance between the negative battery post and the location you are testing. To find the excessive resistance, walk up the wire/cable/circuit towards the battery until you get a reading you expect. The resistance will be between the first place you get a good reading and the last place you got a bad reading.

Tip: try to avoid poking wholes in wires. That just creates a place for moisture to get in and corrode the wire from the inside out over time. It is better to back-probe connections with a small safety pin and touch the meter lead to the safety pin. But if you must poke wholes, seal up the whole with some RTV or better yet some .

Hope that helps.

 

I haven't updated this due to being sick. I will go out in a few hours and put on the new plug wires and also try putting on a new ground strap.

 

Well I put on the plug wires today...nothing changed. Can I run a ground off the water pump? It seems to be the easiest place. This is the first time I've dealt with grounding anything so I'm not too sure

 

Instead of throwing parts at the problem and wasting your time & money, why not diagnose it and fix it right the first time. I gave you very simple to follow instructions on how to find a ground issue. They really aren't that hard to track down and diagnose.

btw, grounding off the water pump won't do anything because the motor is already grounded in at least 2 spots. It also wouldn't provide a very good ground because the ground would go through the pump ->bolts and into the engine block. Again, you'll be wasting your time.

There are no silver bullets for electrical issues. You're going to have to dive in and diagnose it or pay someone to do it for you.

Good luck...

 

I just thought it would be easier to add a new one. I will search for the grounds again today and keep you updated

 

if the grounds are good, have the alternator tested for RFbackfeeding due to a bad diode, anyone who has a vat 40 can test for it, this is not a output test either