Your Essential Diagnostic Tools – Indie Garage
By Dean Law
One of the biggest problems we have today is people who are against oscilloscope technology. They think it’s too strong, it’s too much. But that’s because people are afraid of it, and I can understand that.
When you are afraid of something or you don’t understand something, you are intimidated.
In fact, you have to kiss it. So with oscilloscopes or graphical multimeters, start small: a dual channel, something like that.
Multimeters and Oscilloscopes
Multimeters are good, but they’re almost obsolete because you can’t find bad grounds with a multimeter. It will send you in the wrong direction. I have used multimeters in the past to check for patterns and continuity. For continuity it’s great, but on my oscilloscope, I actually picked up bad grounds. And when I put my scope on it, you can actually see the line trying to pull it down, or trying to turn on and start the computer. You can actually see the computer drivers hitting this, but it happens in two milliseconds. Multimeters are not fast enough to detect this.
So a reach is number one for dropouts, throttle bodies, TPS, any computer control – which is all about cars today.
They have live data that you can read. And most of the time, if you can see that data live, you can do some of your diagnostics on that. It doesn’t have to be a high-end goggle.
For technicians who have a 10-year-old scan tool because you don’t work on a lot of new cars, well, this is going to be obsolete.
New tools are coming. Let’s call them what they are. It is no longer an analysis tool. Scanning is simply checking the codes; it is an interface tool that allows you to read live data and you can also drive some motors from the tool.
So there are certain computer activations that you need to activate to see if it is a computer control problem, a driver problem, or if it is the part you are testing itself.
So if you get a comm while connected to it, you can activate the fuel pump. I have computer control because I can see the commands coming in, the relays switching on. So we have a problem further down the road, but until you do that, you don’t know.
So if you can’t activate the fuel pump itself, you don’t know if it’s a computer problem, ground problem, power problem. So that eliminates a lot of those problems. So interface tools for analysis tools are something very important today.
There are many suppliers of smoke machines. They are great for checking for air leaks or cabin leaks, water intrusion, exhaust leaks. You can get high pressure ones for AC systems. If you have an AC leak that you can’t see, turbocharger cracks, whatever – there are many, many, many uses for smoke machines.
Look for one that has induction heating and has a fan to keep the system cool so it doesn’t shut down.
And having one that has ultraviolet dye is very important. (Be sure to use a dye that is safe for the sensor.) Even though you can’t see the leak and it’s tiny, like looking at a 0.001 inch leak, but it’s spitting out oil, you can use your light to see where this stuff is coming from.
Add these gaskets for exhaust systems, quick gaskets for throttle bodies. Any system you can buy that has a seal – it’s like the one that goes around your arm at the doctor’s office and you pump. So it’s another must-have with a smoke machine.
Today, gas analyzers are important, especially for people who are having trouble trying to get the best gas mileage for their vehicles. So two sensors are working properly – is the catalytic converter working properly, as not only the upstream, but two sensors doing your fuel tuning: upstream of the catalyst and downstream.
Your downline also makes the final fuel adjustment. So if something happens there, it will definitely affect that. And you should know what it is. The gas analyzer will tell you, once you are trained in it, whether the catalytic converter is having issues, whether it is a lean misfire, a rich misfire. You can read all of this. It reads oxygen, it reads hydrocarbons (which is fuel), CO which is carbon monoxide, which you can’t smell and tasteless. So you can use this walking around an exhaust system and then all of a sudden your CO skyrockets; Well, I just found the leak, didn’t I?
So it’s a huge tool, very well used, a versatile tool.
Stay up to date
We find that we replace ours and upgrade the entire system every five to six years. It’s to the point that core updates don’t keep up with the brand new abilities available.
So it’s time to trade so that we can keep up with what’s happening in the world.
Updates are for new tools, such as new interface tools. So you have new tests you can do, even on older vehicles.
They are constantly updated. So you can actually have a new two-way test you haven’t had before, or another PID window you’ve never had before to check the three-way catalytic converter that Toyota just released. Stuff like that.
These things you need to keep in mind because not having them could really hamper your diagnostic times and your abilities to get a job done.
Everyone has favorites.
My number one tool that I bought a few years ago is a wireless DC circuit tester. It has an inductive band, so if you test something on a car, as long as you hold the floor of the car, like the car’s chassis, it will carry the electrical charge through you. It has a little light and a beep too. So if you’re under a dash and checking, just a quick test and you don’t care if it’s five volts or 10 volts as long as the circuit has power, you can kind of tell by the beep if it is at full power or not: you are below and “beep beep”. And then you’re done, then you put it back in your pocket and off you go, right? I use it so much that I have carried the name.
Second on the list I keep on a carabiner: my spark plug spreader. This is another diagnostic tool that sticks with me. I like to put it on my hip. So if I’m diagnosing a misfire or bad fuel mileage or whatever, it’s a tool that a lot of good techs still use too.
A water bottle. If you can’t afford a smoke machine and you have an intake leak, or some type of leak, a bottle of any drink: just poke a small hole in there, then use -it for spraying around entrances. This is another diagnostic tool that many good technicians have. Many people ask, why do you have this on your desk? Well, because you can use it to check for leaks and anything, or even something that is leaking, like a cooling system leak or an AC system leak. You can use it with a bubble solution made with dish soap.