Articles by G. Jerry Truglia

With young techs working in my shop, I find myself spending as much time in the bays with them as I do upstairs working on my training materials. While it makes for long hours and hectic days, it also keeps my own diagnostic skills sharp, and I enjoy passing on what I’ve learned to the guys. Toyota EVAP Fault First First up is a Toyota Avalon (even though the Toyota Scan tool ID’d th
This problem vehicle was a 2005 Ford Crown Victoria 4.6L V8 with a complaint of sometimes being hard to start. The retired owner of this Ford does not drive it much. In fact, this vehicle only had 25,000 miles on the clock. 
The Chevy Volt is an extended range vehicle that is similar to a hybrid vehicle since it also uses an internal combustion engine (ICE). Although the Volt’s ICE is not used in the same way as a conventional hybrid’s ICE, but rather uses the ICE as a generator to charge the HV battery. 
First on the list this month is a 2003 Toyota Highlander 3.0L V6 that came in with a few Diagnostic Trouble Codes (DTCs), then comes a Porsche under water. 
The customer came in with a complaint that his Check Engine light was on. A quick scan easily showed the reason for the complaint. A P0401 (Exhaust Gas Recirculation (EGR) Insufficient Flow) code was found when I checked using Global OBDII’s Mode $03. 
Vacuum leaks and fuel delivery problems are common causes for these common codes, and you might be tempted to focus immediately on these. But there are many other causes that can illuminate the MIL for the P0171 and P0174 DTCs that you also need to consider.
The first story shares a lesson on not getting caught with your pants down, the other is a tale of a BMW clutch gone sour, and the third? Well, the third is just for your enjoyment! 
You connect a scope the same way you would connect a multimeter to test for voltage. The difference is rather than looking at voltage numbers you are looking at a waveform.  
New DTCs appearing after a repair is more common than you might think. The reasons why are several, but the most common are a failure to make sure all the OBDII test monitors are Ready, failure to address pending Diagnostic Trouble Codes (DTCs), and not investigating the cause of Mode $06 failed test results.
In our first case study we are using the Toyota Techstream OE factory scan tool on a 2005 Scion tC. Let’s take a look at one of the most important pieces of scan data that many of us overlook, monitor information.