Most problems with emissions systems are caused by poor maintenance of the vehicle.
Ben Johnson, director of global product development, service tools and education products with Delphi Corp. in Troy, Mich. said North American vehicle owners are not often encouraged or taught the necessity of regular vehicle maintenance, including the emission system, of their vehicles. Too often, many car owners will only bring a vehicle in for an inspection and a check of its emission system when the little “Check Engine” light goes on.
But lack of maintenance awareness on the part of vehicle owners also comes from service technicians not realizing the upsell opportunities for emission systems maintenance that is sitting in the palms of their hands.
“We too often look at our diagnostic tools as only diagnostic tools,” Johnson said. “But we have to be very conscious that those tools are also marketing tools as well. The independent service shop today and its technicians not only need to have the (technical) knowledge and tools to repair a problem, but they also need to use those tools to proactively look for problems before they become something more serious.”
For example, when a car comes in for something as simple as an oil change, a technician can take a few minutes to do a diagnostic check on the vehicle, for example, taking a look at the short-term and long-term fuel trim.
Johnson said if the technician finds a large variance in the long-term and short-term fuel trim, that can be an indication of a problem with an emission system. What is important to remember is this problem would only be apparent to the technician if the technician decides to do a check when the vehicle comes in. In most cases, that problem would not be apparent to the driver, as the car, even with this variance, would seem to run fine, as the on-board ECM system compensates for the variance, even as it signals silently there is something amiss.
“Today’s ECM and PCM systems are so powerful, they often mask symptoms and failures prior to something becoming an absolute failure,” said Bill Wrubel, manager of aftermarket service and support with Delphi Corp. in Troy, Mich. “Let’s say you have an EGR valve that has begun to carbon up and leak exhaust. It is not turning the ‘Check Engine’ light on because the computer adjusts and compensates, and most times the vehicle owner will not notice anything is amiss. If they really pay attention, they might notice a reduction in fuel economy, but the car is not obviously backfiring or running improperly.”
Because the ECM is critical in maintaining a vehicle’s emission system, car makers periodically release flash updates for the ECM. These flash updates are meant to help the vehicle operate smoothly and efficiently over its useful life. Service providers often have difficulty with these updates as most OEMs are reluctant to give the new calibrations out and service shops often lack the necessary tools to do the flash upgrades.
To make flash upgrading available to the independents, and to give them a crack at getting the valuable dollars that come with such a service, Delphi has a Universal Reflash Tool that incorporates the Delphi reprogramming bench, comes with on-board and off-board cables, and is wireless and bi-directional scan tool capable.
Jeff Elder, marketing manager with Blue Streak Electronics in Concorde, Ont. said technicians, when getting vehicles in the bays, should check to see if there are any new calibrations for the vehicle right away.
“It is just a general and a very good repair procedure to check the customer’s VIN number against the OEM sources to see if calibration updates are available,” Elder said. “Making sure the ECM is up-to-date will often prevent the technician from wasting time looking for problems with other emission parts that may be working just fine, but he or she may believe are not because the ECM has not been updated.”
Blue Streak’s iFlash universal flash programmer comes with a 2534 Global Programmer Interface, an RS-232, USB, and OBDII Quicklink cable; and the iFlash is capable of GM TIS 2000 programing, SAE J2534 programming and Chrysler VIN and mileage programming.
Because most vehicles manufactured in North America since 1993 have flash-upgradable ECMs, Elder believes technicians should make it a point to check and periodically upgrade ECMs in order to maintain emissions systems and get peak fuel efficiency.
“As the ECMs have become more sophisticated, the overall emission and fuel efficiency has improved greatly,” Elder added. “To maintain that high efficiency, it is critical to maintain the ECM and that a shop have access to flash upgrading.”
Valve, spark plugs and O2 sensors
If the ECM system is the proverbial “brain” of the vehicle, then the valves, spark plugs and O2 sensor are the actual body parts of the emission system. Because of the extreme environment these parts work within, they are often the first things to wear out and need replacing in an emission system.
The problem is the parts can have problems which are not readily apparent many times when a person brings a vehicle into a shop.
“Right now, there are millions of vehicles that have a ‘Check Engine’ light on for various reasons,” said Brad Brunken, product manager for GM/ACDelco ignition, emission and wire and cables products in Grand Blanc, Mich. “If the driver overlooks mentioning this, sometimes the technician neglects to look at the instrument panel or driver information center to see whether there is a ‘Check Engine’ light on. Many vehicles are calibrated to work even when a mass airflow sensor, EGR valve or other emissions components fail.”
Brunken recommends technicians, when they get a car coming in for maintenance work, should first let the car warm up and see if there is a ‘Check Engine’ light on. And then the technician should plug in their scan tool and see what is going on.
“This simple procedure is a tremendous opportunity for the technician to not only catch a problem the vehicle owner may not be aware of, but it also provides a tremendous opportunity to sell bonus business.”
Delphi’s Wrubel points to two places that can provide such bonus business: the PCV and EGR valves. If a car is not on a regular maintenance schedule, these valves can begin to slowly fail because of a lack of maintenance. An excess of carbon in the emission system can begin to cause carbon build-up on the valve, thereby diluting the air/fuel mixture and the overall engine performance. If the owner of the vehicle has been neglectful about regularly changing the oil, that can also slowly begin to affect the PCV valve.
“Over time, the oil gets thick and it will collect on the valve and it will become slow,” Wrubel said.
When the valve becomes clogged, vapors will back up into the air filter housing or will build up and break through seals and cause an oil leak.
“With a scan tool, there will be indications in the OBDII-type emissions testing readings,” Wrubel added.
Spark plugs and O2 sensor are another set of parts that take a lot of punishment in an emission system and need to be regularly checked and replaced.
Jeff Desveaux, senior product manager with NGK Spark Plugs Canada Ltd. in Markham, Ont. said with spark plugs, even the ones touted as being long-lasting or having extended life, a technician should regularly remove a couple of the plugs and give them a visual inspection. Such an inspection can find indications of wear or deposits that could indicate a problem somewhere else in the emission system or engine.
If the spark plug is dry- or wet-fouled, it could be an indication that the air-fuel mixture is too rich; deposits on the plug may mean that oil is entering the combustion chamber; and a melted electrode may signal that the air-fuel mixture is too lean.
Chris Harrison, product manager for oxygen sensor and wire sets with NGK Spark Plugs in Markham, Ont. said the life of an O2 sensor is very much dependent on how well the vehicle has been maintained and even if a sensor is dirty it does not necessarily mean it is not operating properly.
“But if you have heavy white deposits on the protection tube it could be an indication of silicone poisoning; or if it is getting too white, the system is running too hot; or if you see the sensor getting a little dark, or dark brown, it is running too rich.”
Robert Bosch Group points out that other signs of discoloration and fouling can indicate other problems with the engine and other components. A light colouring or graining discoloration on the O2 sensor could indicate that anti-freeze has gotten into the system. If that if the case, a technician should check for a cracked block, cylinder head or intake manifold. A dark brown discolouration on the O2 sensor could indicate high engine oil consumption which may be caused by worn engine components like valve guides, rings and gaskets.