Sensor Archives - Page 3 of 4 - Import Car
Tech Tip: Hyundai Has Check Engine Light On with Fuel System Lean Code

The check engine light is on with a post catalyst fuel system lean code P2096, an oxygen (O2) sensor stuck lean B1/S2 code P2270, and an O2 sensor no activity B1/S2 code P0140.

Diagnostic Dilemmas: The Diagnostic Tail Gunner – Surviving in the Age of Information

One of the first survival skills my professor taught is called “preparatory set,” which is simply the act of preparing to do something. Each of us engages in preparatory set when we open our toolboxes each morning. The very act of opening our toolbox signals to our mind that we’re ready to go to work and deal with the day’s issues.

Diagnostic Solutions: Exhaust Restriction Diagnosis

To put exhaust restriction diagnostics in perspective, import specialist shops have been dealing with loss-of-power complaints caused by exhaust restriction since catalytic converters were popularly introduced in 1974. Early “cats” experienced frequent failure because the carbureted engines of that era were notorious for poor fuel control.

Tech Feature: Exhaust Leaks and the Stoichiometric Ratio

When I was a kid, I used to watch my dad, who started out as a diesel mechanic, tune up cars and trucks from time to time. He would turn the adjustment screws on the carburetor until the engine smoothed out and started to purr. Then, after listening closely to the rumbling of the motor, the adjustment screws would get one final tweak. He would always bend down and cup his hand around the belching tail pipe exhaust and take a big sniff of the fumes, and then go back to his adjustments. That was back in the 60s and 70s before PCMs, O2 sensors and catalytic converters.

Tech Tip: Kia MIL Illumination with Front Heated O2 Sensor DTCS

If a 2004-’06 Spectra 2.0L exhibits an MIL on

Tech Tip: Nissan’s Engine Idle Speed is 25 RPM too High

If you confirm the idle, in Park or Neutral, is more than 25 rpm above specification (with the engine warm), and/or DTC P0507 (ISC System) is stored, this incident may be the result of recent cleaning or replacement of the throttle body. The vehicle “in-use” learned idle may be higher after throttle body deposits are reduced (by cleaning or replacement).

Diagnostic Dilemmas: Solving No-Code Performance Complaints

For many diagnostic techs, nothing is more discouraging and time-consuming than dealing with a no-code driveability complaint. Today’s second-generation On-Board Diagnostics II (OBD II) can be extremely sophisticated because the OBD II powertrain control modules (PCMs) in modern vehicles have far more computing capacity than did the older, pre-1996 OBD I vehicles. Nevertheless, we occasionally have to deal with a no-code performance complaint on a modern OBD II vehicle.

Troubleshooting Wideband O2 Sensors

Many late-model imports such as Honda, Toyota, Volkswagen and others use Air/Fuel sensors rather than conventional oxygen sensors to monitor the exhaust gases coming out of the engine. What’s the difference? An air/fuel sensor can read a much wider and leaner range of fuel mixtures than a conventional O2 sensor. That’s why they’re also called “wideband” O2 sensors.

Diagostic Dilemmas: Lost in ‘The Diagnostic Woods’

This real-world case study of a 2002 Chevy S-10 pickup, a 1995 Buick and a 1995 Lincoln Town Car illustrates why “chasing” trouble codes can get you lost in the Diagnostic Woods.

Tech Tip: Toyota MIL On with DTCs Set in Subfreezing Temperatures

Following a cold soak in subfreezing ambient temperatures, some 2003-’08 Corolla and Matrix vehicles equipped with a 1ZZ-FE engine may exhibit an MIL on with one or more of the following DTCs as the result of a vacuum leak at the intake manifold.

Pulling Codes: The Story of Code P0446

This is the first in a series of investigations covering many states’ top emissions-related codes. Our goal in this report is to discuss the characteristics of the P0446 code as it applies to many GM systems.

Tech Tip: Follow These Steps Prior to Replacing Kia’s Catalytic Converter After Finding DTC P0422

Kia’s OBD II engine management systems use dual oxygen sensors, which among other things allow monitoring of the efficiency of the Manifold Catalytic Converter (MCC), also referred to as the “warmup” cat. Some technicians who retrieve DTC P0422 – Main Catalyst Efficiency Below Threshold (Bank 1) mistakenly replace the catalytic converter under the floor of the vehicle (possibly because the converter under the car has been referred to as the “main” catalyst). This leads to repeat repairs, unnecessary expense and customer dissatisfaction.