Driveability Archives - Page 11 of 13 - UnderhoodService
Tech Tip: Cool Fix for a Ford Diesel

A Ford truck, SUV or van owner may complain of a crank/no-start condition, lack of power and coolant leak. Some vehicles equipped with a 6.0L diesel engine may exhibit those symptoms, along with oil in the coolant. The coolant leak creates a low coolant condition, which may cause the engine to overheat or result in no cabin heat.

Tech Tip: Diagnosing Ford F-250 Engine Miss

A 1999 Ford F-250 5.4L has an engine miss and the Check Engine light is on with code P0304 in its memory. Check for coolant dripping onto the #4 coil (passenger side rear cylinder) from the hose fitting directly above it. If coolant has dripped onto the coil, tighten the clamp and replace the coil, as it is almost always damaged by the coolant leak.

Tech Tip: Chrysler Intrepid Won’t Shift, DTCs Set

Automatic overdrive transmission goes into second gear (limp-in mode) and will not shift, and trouble codes for the transmission solenoid pack are stored in memory.

Tech Feature: Mazda Driveability Diagnostics and Check Engine Light Complaints

From a torn air intake hose to ignition system concerns, Bob Dowie tackles driveability issues as well as some of the more common ailments that will bring Mazda vehicles into your bays with a check engine lamp complaint.

Tech Feature: What’s New in Spark Plug & Ignition Cable Technology

Ignition systems have changed a great deal in recent years, with coil-on-plug (COP) ignition systems being the most common setup on many late-model engines. Car makers like COP ignition systems for a variety of reasons. The main one is that mounting a small ignition coil over each spark plug gets rid of the troublesome spark plug wires. Plug wires are vulnerable to heat and vibration damage, and can become a source of ignition misfire if they become wet.

Tech Feature: Rediscovering Your DMM Relationship

Sometimes we become so caught up in leading-edge diagnostic technology that we forget that a professional-grade digital volt-ohm meter (DVOM) or digital multimeter (DMM) is a vital tool in any technician’s diagnostic arsenal.

Mercedes ‘CAN’ Diagnostics — Uncovering Faults Speeds The Repair Process

Dealing with frustrating error messages on your scanner? Import Specialist Contributor Larry Bailly covers some of the more common faults when dealing with Mercedes CAN wiring, what it takes to plan and achieve diagnostic success, and the places to look for the cause of faults.

Tech Feature: Diagnosing Intermittent Driveability Issues

Intermittent driveability problems of any kind are always a challenge to diagnose. When a customer brings you a vehicle and complains of a stalling problem, you may not have much to go on other than their description of what is happening and when it happens. The more information you can get out of them the better, because you’ll likely need all the details you can get to narrow down the list of possible causes. Many times, there will be no check engine light ….

Mode $06 Diagnostic Update

Mode $06 has been around since the introduction of second-generation onboard diagnostic (OBD II) systems back in the mid-1990s. Essentially, Mode $06 is the raw test data the OBD II system uses to evaluate the operating status of various components in the engine management and emission control systems

Finding the Failure Pattern

but that’s about it when it comes to diagnosing random, no-code malfunctions. Lucky or not, the chances of locating the cause of a random, no-code malfunction can be increased by determining the sequence of events needed to trigger the malfunction. Determining this sequence of events is what I call, “Finding the Failure Pattern.” From the

Diagnosing Intermittent Stalling Issues

Intermittent driveability problems of any kind are always a challenge to diagnose. When a customer brings you a vehicle and complains of a stalling problem, you may not have much to go on other than their description of what’s happening and when it happens. The more information you can get out of them the better,

Downloading Repairs

Have you looked at technical service bulletins lately? Especially ones for vehicles built since 2004? The fixes have changed drastically. I remember a time, not too long ago when the fix in a typical TSB was to install an updated part. From where I stand now in a Ford dealership, it seems like the hardware