Hey everyone, first post here! I have a big issue with my 2003 XLT 3.0 automatic that I'm looking for some help troubleshooting. Here goes the story:

While parking at the store, I noticed speedometer is bouncing only at idle. I turned off the ignition and heard a few rapid click click click sounds from the dash area. Started right up after leaving and I pulled into the road when suddenly the engine dies, ABS light flashes, and the dash is all lit up. Fortunately I was only doing 10, and I come onto the curb and turn the key off and restart it. After restarting, the ABS light is on and then goes off and on a few times.

I pull over and turn the car off, at which point the clicking goes crazy-- rapid clicking coming from under the column. Turning the key to run or start does nothing, clicking continues. At this point I get worried that something is going to start on fire or something so I disconnect the battery. Clicking stops, and resumes when I reconnect. I'm able to get it home by turning it off and restarting, but it kept clicking and I had to disconnect battery to stop it. Only code is a lean bank 2 which has been there for months and I assume is unrelated. Battery reads 12.46 volts, but the terminals are a little crusty looking.

Here's a I took of it clicking with the key off, appears to come from this black plastic box that has some relays inside: https://youtube.com/shorts/oypWc7lIjNg?feature=share

The speedometer bouncing has occured in the past and I was able to get it to go away by cleaning the rear speed sensor connector. Never had any issues with clicking before, although the truck does have a rough idle and intermittent rough starting/sputtering which I will have to make a separate thread about.

I've been a huge fan of this forum since I got my truck last year, and I hope someone can help me figure this latest "project" out!

 

Well after doing some more research into this issue, I found other people with similar problems (clicking after key off, speedo bouncing) typically had poor battery connections or grounding. So I went ahead and removed, cleaned up the front body ground, engine block ground, and firewall ground, and then retightened with some grease over top for good measure. Then I removed the old crusty battery terminals and replaced them, again coated with grease.

She started up very quick, ran like hell for a half a minute until the engine relearned the fuel trims, and now seems to be running without issue. No clicking or speedo bouncing at idle. In fact, she's running better than ever! We'll see if the problem rears up again in the next week.