Thursday, 22 March 2012 15:59

What If You’re Looking for More than One Waldo?

Written by Gonzo Weaver

OK, I really do fix cars for a living. I take a car that’s acting up, locate the problem, and make the appropriate repair. Sometimes I haven’t a clue where to look when I start, but with a few proper tools, a little ingenuity, and a whole lot of experience I’ll find the problem eventually.

It’s like finding Waldo, that nerdy little guy dressed in red and white who travels a lot and specializes in challenging people to locate him. He sometimes hides in plain sight. You’ll usually have to look closely to find him. Except my “Waldo” doesn’t wear a red and white cap to give himself away. My Waldo is usually something to do with a component or part that has failed, or has decided to be difficult. I sometimes think that these weird repair jobs that end up at my shop are like an elaborate game of “who can find Waldo first?”

I’m not always the first guy to try and find Waldo. A lot of times a customer will take their car to a relative or next door neighbor, or they’ll find the cheapest shop or the closest garage in their area. I’ll hear a customer tell me they always go to a certain shop for all their repairs, so they think nothing of going to a specialist for repairs. But, when that doesn’t work it’s time to ask for a recommendation for a shop that can make the repairs. Now, of course, this isn’t true of everyone. A lot of people have a family mechanic they have used for years, while others believe the dealership is the only place to go for repairs. Whichever or whatever way works for each and everyone is just fine with me. One way or another somebody has to find Waldo.

When it comes to cars, Waldo can be pretty crafty. He can be hiding in thousands of places. He can be under the hood, behind the dash, in the trunk, or under the seat. He can be well concealed or under layers of components—carpet, plastic, or engine parts. With today’s cars he can even be inside a computer lurking about in the form of a corrupted bit of information. I never know where he’ll show up, but I’ll do my best to find him. The other day I was on a Waldo hunt for a whacked out gas gauge. The fuel gauge was stuck on empty on this ‘03 Ford Van. It came from another shop after they had given up on it. The shop had already tried a new sending unit in the tank, but it only lasted a day or two before the gauge quit again.

So where is that little beanie cap wearing weirdo hiding this time? I started with behind the steering wheel. After doing the self test on the dash it was clear the gauge was not responding, so I broke out the gauge simulator and hooked it up to the fuel gauge. Even with the tester adjusted to 160 ohms (full tank reading) it never budged off of empty. Gotcha Waldo!  You’re in the instrument cluster… aha! Got ya this time for sure ya skinny little twerp!

I got the new cluster approved and installed it the next day. I hooked up to the scanner, checked that all the programming needed was done. That’s typical stuff… mileage, tire size, etc …  not a big deal (with the right scanner, an IDS in this case or the dealer parts department can set most of it up for you when you order it. Actual programming needs vary from year to year, so be careful to follow all manufacturer’s directions). I was so convinced that I had this one I didn’t think I needed to recheck my work, so I was in for a surprise when the gas gauge didn’t move right away. I’ve seen this before. It can take a minute or two, or up to 20 minutes if the key was on while filling up the tank. I didn’t recall turning the key on when I was installing the new cluster, but by the time I had the van off the lift and backed out of the shop the gauge was working. Done, problem solved. Waldo, you’re out-of-here!

Boy was I wrong. Seems old Waldo had to come back just a few days later. The gauge is back on empty again just as it did with the first shop. Now what is he doing? Waldo is a crafty kind of nerd. Is he messing with me? I’m about to “go mechanic” on his butt.

Back to the gauge tester again. This time the gauge reacted with every movement and changed with every setting I could put it through on the tester. I knew the empty reading on this tank is around 15 ohms and a full tank is 160, so I should have a reading somewhere in between those readings from the tank sender. It was 16 ohms? Oh, come on. Is this tank empty? I gave the tank a couple of knocks with my knuckle “rap, rap, rap” and asked sheepishly, “You in there, Waldo?”

I got an approval to drop the tank down to check it further. I could tell the other shop changed the tank sending unit. They had butt-connected the lead together (Gee, ya could have just disconnected it) but I did notice something rather strange about the sending unit. The float was bent around the fuel pump and an edge of the bail was trapped against the actual fuel pump bracket. Waldo is up to something here, and it’s not the sender.

I grabbed a flashlight and looked down in the tank. There inside the tank is the tray that the fuel pump rests in. It’s mainly there as a way to control the sloshing affect of the fuel and to help give the gauge a steady reading. The only thing was the tray wasn’t staying in place. It had broken free from the bottom of the tank and was sliding back and forth as the van drove down the road. “Waldo, you’ve been a very naughty little fellow,” I said to myself.

The only thing that made sense about the dash being bad was that somebody must have tried to send voltage back up the sending wires to the dash, and it probably knocked the gauge out. It wouldn’t have been hard to do with the gauge and fuel pump leads all in the same connector. Somebody could have easily (accidently I hope) crossed the wrong leads, which created another Waldo. While the original Waldo remained in hiding inside the gas tank the whole time.

Now I just have to tell the customer where I found him at this time. Great, just great—two Waldo’s in two places in one car. I think I’ll let Waldo explain this one to the owner himself.

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