Tech Tip: Collisions Lead to Toyota EVAP Issues
The Malfunction Indicator Light (MIL) is on in a 2004 Toyota Corolla, and codes P0441, P0442 and P0446 are set. It was determined that the vehicle was hit in the left front. Verify that the Vacuum Switching Valve (VSV) for the pressure sensor (located on the canister) operates correctly. This is a normally ….
Tech Tip: The PCM Relies on Good Information from the Oxygen Sensors
Do you know your oxygen sensors? Oxygen sensors have been used for more than a quarter of a century, dating back to 1980 when the first computerized engine control systems appeared. The oxygen (O2) sensor is part of the fuel management system. It monitors unburned oxygen in the exhaust. The powertrain control module (PCM) uses this information to determine if the fuel mixture is rich (too much fuel) or lean (not enough fuel) ….
Tech Tip: Larry Carley Covers the Top 10 Domestic Diagnostic Codes and Fixes
Some people think a code is all you need to fix a fault and turn off the Check Engine Light (or Malfunction Indicator Lamp or MIL). A diagnostic trouble code (DTC) certainly helps, but it only tells you that some kind of fault has occurred, and maybe the circuit or component associated with the fault. But no code by itself can tell you which part to replace, because in many instances any one of several causes may have set the code ….
Decoding the Past
“I’d like for you to hook it up to the code machine and see what it says to replace” – anonymous customer Sound about right? It sure does. Of course, as auto repair professionals, we know better. We know that reading the code is not diagnostics, but rather that is where diagnostics might begin. We
Tech Tip: Top 10 Domestic Diagnostic Codes and Fixes
A Check Engine Light that’s illuminated is always a sign that something is wrong. But what? You usually can’t tell until you plug in a code reader or scan tool and read out the code(s) that have turned on the light. At least then you have a starting point for further diagnosis. Some people think a code is all you need to fix a fault and turn off the Check Engine Light. A diagnostic trouble code certainly helps, but it only tells you that some kind of fault has occurred, and maybe the circuit or component associated with the fault.
Who’s at Fault?…Top 10 Domestic Diagnostic Codes & Fixes
A Check Engine Light that’s illuminated is always a sign that something is wrong. But what? You usually can’t tell until you plug in a code reader or scan tool and read out the code(s) that have turned on the light. At least then you have a starting point for further diagnosis. Some people think
Tech Tip: MIL Illuminated, System Lean in Ford/Lincoln/Mercury Vehicles
This article is intended to aid in diagnosing DTCs P0171, P0174, P1130, P1131, P1150, P1151, P2195 or P2197 (system lean or lack of HEGO switches) when a vacuum leak is present. HEGO sensors, MAF sensors and PCM replacements are not an effective repair when a vacuum leak is causing the above DTCs.
Tech Tip: MIL Illuminated, System Lean in Ford/Lincoln/Mercury Vehicles
This article is intended to aid in diagnosing DTCs P0171, P0174, P1130, P1131, P1150, P1151, P2195 or P2197 (system lean or lack of HEGO switches) when a vacuum leak is present. HEGO sensors, MAF sensors and PCM replacements are not an effective repair when a vacuum leak is causing the above DTCs.
Diagnostic Oddities
This article is dedicated to some Ford specific issues that, after being brought to light, can save your shop thousands of dollars in wasted time and liability. There may be some other makes out there with some similar designs and quirks, but the only technical references will be for Ford vehicles. By Glen Beanard Giddy
Tech Tip: Dirty Fuel Injectors Can Result in Driveability and Performance Problems
When dirt or fuel varnish deposits build up in the injector orifice, it creates a restriction that reduces the amount of fuel delivered with each squirt. Dirty injectors, therefore, run lean and don’t deliver as much fuel as the engine needs.