Tool Q&A: Using inspection tools

Cappert covers questions borescopes, fuel pressure testing, vacuum pumps and more


A: We all know we can’t be shielded from improvements in technology and the new features it continually brings, but there are a few things you can do to make sure the borescope you choose can have a long, healthy and productive life in your shop environment.

Start by making sure your purchase is protected by a strong warranty and support network, in the event you have any problems with your borescope purchase. Also consider optional accessories such as extended probes and related incidentals including magnets, mirrors and hooks. Some of these options may not make sense now, but knowing they’re available can reinforce the viability of your purchase going forward. Lastly, don’t forget to ask your rep about any available training for the tool, to help you get up to speed quickly.

Q: Our shop encounters a wide range of electrical relay failures on a growing number of makes and models. Is there a tool that can quickly help us inspect or diagnose these relays?

A: Yes, a deluxe relay test set fits the bill perfectly for these applications. The set comes with a set of relay pliers to make removing and installing relays easier, along with a host of adapters and jumper leads to facilitate connection of a multimeter or other test equipment. Through use of this test set, it eliminates the need to pierce wiring insulation for testing, which could otherwise lead to further electrical problems down the road. Of course, always follow recommended diagnostic procedures when using this set for diagnosing relays.

Q: We want to work on some European models that use Bosch KE-Jetronic fuel injection systems. What do we need to perform fuel-pressure connections on these vehicles?

A: European imports with Bosch K-Jetronic or KE-Jetronic fuel injection differ slightly from most conventional electronic injection systems when it comes to connections and testing. Since these systems operate at higher pressures than most electronic systems, make sure your gauge reads a maximum of at least 630 kPa (90 psi). You also need a special adapter hose with shut-off valve and some other small adapters to connect to various makes of cars. Tee into the control pressure line with an adapter. The control pressure line connects the fuel distributor and the control pressure regulator. Follow a reliable shop manual to the letter when taking your pressure readings.

Q: We mostly work on domestic cars that come equipped with a fuel pressure test port for connecting a fuel pressure test gauge. As our services have expanded into Asian makes, there is no test port. What’s up?

A: Asian makes typically don’t have a fuel pressure test port, but the truth is even larger than that. Asian engines used in so-called domestic chassis may also be lacking a test port. Connecting to most Nissan, Mazda and Mitsubishi models requires the same type of series connection.

First, locate the fuel filter in the engine compartment. Then, disconnect the outlet line and connect a tee fitting between the outlet line and the fuel filter. Connect your gauge and take your readings. Toyota and Lexus engines commonly use a cold start injector. With that in mind, Toyota engineers designate this spot as the access point for fuel pressure testing. You’ll need a special fitting to connect to these engines. In some cases, you may need to connect at the outlet of the fuel filter. If you’re using an aftermarket gauge and adapter hook-up, the connection is similar. Nevertheless, it’s best that you refer to the user’s manual and follow the gauge maker’s recommendations.

To tap into a Honda or Acura injection system, you’ll need a special 6mm adapter. To install it, remove the 6mm bolt from the top of the fitting on the outlet line at the fuel filter. The filter mounts to the firewall at the right side of the engine compartment. Then, thread the adapter into place and tighten. Connect your gauge and follow the manufacturer’s procedures and specifications for checking fuel pressure.

Q: We see a fair number of cars with failed vacuum motors. Is there a tool that can help us check out vacuum motors quickly?

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