I Hate When That Happens is a monthly column that appears in the
St. Francis Community Courier written by Randy Gerdin.

It’s hot!

Written by Randy Gerdin on July 1, 2017

This year we seemed to go from winter to summer in about 10 days. I heat my house with wood and had the wood furnace on in the morning and the air conditioning on the same evening when we got home from work. Crazy! We have also been seeing a number of vehicles in the shop lately with their air conditioners (AC) not working. AC can be a confusing issue. There are a lot of different configurations on the market. Some vehicles have standard AC, some have dual climate control so that each side of the front seating area can control their own temperature. Some SUV’s, CUV’s, and vans have rear heat and AC. This means that the AC system has to run under or inside the body to a rear evaporator core (the part that gets cold) in the rear for the far back seating positions. The parts under the hood are the same, but they branch off to provide cooling to the rear.

Since about 1992 all vehicles use a refrigerant (known in the trade as “freon”) called R134a. This is the industry standard and is what all the manufactures have used for years. In some very new cars, the manufactures are starting to switch over to another refrigerant that is supposed to be more environmentally friendly. Unless you have a brand new model of a certain make and model, you most likely have R134a. I have read articles about people trying to substitute other chemicals into the system. These alternatives are not approved by the manufacture and can actually harm the system. R134a in an uncompressed state is a gas, or vapor. When compressed or pressurized, it is a liquid with a boiling point of -26.3 degrees C. That is cold. So when our vehicles are just sitting around not being driven, the freon is in a gaseous state. When we start the engine and turn on the AC the magic begins.

Our car systems work basically the same way as our home AC or a refrigerator. The freon is pumped around with a compressor and changes state from a gas to a liquid and back to a gas again and out comes cold air. We in Minnesota have a bit of a unique situation with our AC systems. The AC actually will come on in certain situations when the ambient temp is cold and we have the defrosters on. This helps to keep fog from forming on the inside of the windshield. Also, here in the colder climates, we have the unique problem of our systems retaining their charge. It is not that uncommon on a six to ten-year old vehicle to have to charge it up every year or so. Unless we find a specific leak, the systems over the winter can slowly lose their freon due to the contraction in all the fittings and O-rings that seal up the system. In some cases, freon just seeps out.

In many cases, freon leaks are difficult to locate. The standard practice these days is to evacuate the system and let it sit in a vacuum state and see if the system will retain its vacuum. If it does, then a small amount of ultra-violet dye is added and the system is driven down the road to circulate the Freon. Then a black light is used to look for a leak. We also use an electronic leak detector to help isolate leaks. Very small leaks can be difficult to find. Especially since so much of the system is hidden inside the dash, in front of the radiator, behind the engine, inside the body or inside the rear evaporator case in a rear unit. In many cases if a leak is not initially found, the driver may have to drive for a while and return to the shop for further inspection. In some cases, parts of the vehicle will need to be removed to inspect unseen parts. Sometimes the leak is found other times we just have to keep looking.

One word of caution, NEVER EVER add AC sealer of any kind to the system. It is never recommended and can actually plug up the entire system. We saw it twice last week. The other problem with sealers of any kind is that if a shop is unaware of the chemical in a system and they hook up their AC machine and it contaminates their machine, the AC charging/recovery machine can be damaged beyond repair. These machines are thousands of dollars. Again, please don’t try and cheat the system with a mechanic in a can. It can bite you. I Hate When That Happens!

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Info, info, info!

Written by Randy Gerdin on May 1, 2017

Last week, we had one of our regular clients drop off his late-model pick-up truck. He said his main concern was that the vehicle started okay in the morning, when the engine was cold, but started really hard after the engine was warmed up. Of course, our brain immediately starts thinking of the possibilities. Is it a fuel pressure problem? Is the truck loosing spark when the engine is warm? Is the computer failing to operate the injectors properly when warmed up? All these are possibilities for this symptom. As he was walking out the door he said, “I almost forgot, could you please check out why the temperature gauge is not reading?” So not trying to jump to any conclusion, we wrote up the repair order. “Hard starting after engine is warmed up and inspect system as to why the temperature gauge is not working.”

The next day, we began work on the truck. We verified that it started up fine when cold and we test-drove the truck about 10 miles. We shut off the truck and had to crank over the engine numerous times before it would restart. We also verified that the temperature gauge was not working. The technician started by checking the fuel pressure, spark, etc., and all the basics were there. We then hooked up our factory scanner. We found that the computer sensor was relaying an engine temperature of only 70 degrees. Clearly the engine was much hotter, around 200 degrees. Further circuit testing found that the engine coolant temperature sensor was defective and was sending inaccurate information to the computer, and the computer was not providing the proper amount of fuel to the engine. In fact, it was over fueling the engine. This was also the cause of the engine temperature gauge not reading properly. This is the same sensor that informs the dash gauge of the engine temperature. The computer uses this temperature information to calculate the fuel and timing needed to run the engine and time the transmission at the various engine temperatures.

We often see a vehicle come in with the check engine light on where the customer’s concern is they have poor heat coming out of the heater during the winter. Often, we find that the engine coolant temperature is too low, causing poor heat. The engine computer monitors the temperature continuously to make the proper fuel and timing adjustments. In many of these cases, we find the engine thermostat is not controlling properly or is stuck open, not letting the engine reach its normal operating temperature. The point is, one thing affects another. You may think you have two problems, but perhaps you only have one issue.

We often see vehicles come in running poorly and we find 5-6 diagnostic codes stored in the computer’s memory. Often, there is only one issue that may trigger all of these additional codes. As with many things, information is power. We would rather have more information than we actually need than less. In many cases, we end up having to contact the driver to ask a question that may seem unrelated to their original concern. We have some clients who actually will write out or type out a list of their concerns along with the symptoms. This can save so much diagnostic time for us and in turn will cost the client less. Time is money, as they say.
After years of working with vehicles, we have gotten pretty good at asking the right questions, but sometimes we still need more information. I cannot count the number of times that I have thought, “I wish the driver would have told me that in the beginning”. In our fast pace world, I know that folks sometimes just forget to mention symptoms or concern. It seems that people are always in a hurry.

From the repair shop’s perspective, we would rather spend a bit more time up front and get the complete story. This way, we do not have to try to contact the owner for more information. Also, it is important on the day your vehicle is in for service you are available to be contacted. We use the phone, of course, as well as e-mail and texting in order to communicate with our clients. The worst thing is needing to know more information and you are stuck until you can get in contact with the client. I Hate When That Happens!

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Old vs. New

Written by Randy Gerdin on March 1, 2017

We have a fantastic client who has many different cars and trucks. The other day he brought in his 1941 Cadillac, a very, very nice car. This vehicle has a unique style that you just don’t see anymore. Of course, it has the “40’s” look. Wide white wall tires, long hood, rear fender skirts, lower front end, and distinctive passenger compartment. The car, of course, has running boards, and yes, there is real wood in them. He purchased the car and was working on it himself. It needed a front-end alignment and was also running poorly. The suspension and the engine were not original to the car, so he had to special order a number of the parts in order to complete this project. We got the front-end set up and went to work on why it was running so poorly. He had already replaced a number of the fuel system components and wanted us to install the ignition components. After we installed them, it still ran poorly.

Well, I am the “old” guy around our shop and even this car was made before my time. The technician that was working on it had installed the parts, but had limited experience with how to set everything up. So we dug though the shop and found a timing light, tachometer, and dwell meter. I used to use these tools daily, but had not had the call to use them in years. Also, my eyes are not what they used to be, so that is another challenge, but we started in. I knew what to do, but was unable to see some of the finer items and really had a hard time setting the gap on the points, etc. So, it took on a tag team effort, an old mind and someone with good eyes.

After messing with it a while, I felt the engine was running lean, the carburetor was not flowing enough gasoline into the engine. We knew the fuel supply was adequate, so the problem had to be inside the carburetor. The owner had purchased and installed a new carburetor, so it should be good. We pondered for a while, tried a few tricks I knew from years ago, but no luck. So we started to take the carburetor apart. It had been many years since I had one of this particular model carburetors apart, so I was remembering as we went. We took the front bowl cover off and found that there was a bunch of rusty looking crud in it. We figured if that stuff is in the bowl, then it probably is everywhere else inside the carburetor as well. We cleaned it out, removed the fixed jets, and cleaned everything we could.

Putting it back together was another chore. There are multiple items that need to line up correctly while the gaskets and O-ring must stay in place. After a couple attempts, we finally got it together with no leaks, but it still ran poorly. I had to take a phone call and when I returned, the car was running well. I asked what he did and he said he tried one of the old tricks I knew and it worked. We adjusted the idle mixture and idle speed, and down the road it went. It was then on to the next job sitting in the adjacent stall.

This was a late-model pickup with an engine misfire and an unusually loud engine noise. And I mean LOUD. We were about to condemn the engine, but a few things did not add up for us, so we kept working to find the root cause of the problem. After some research, a few phone calls, and a little investigation, we found the engine fuel management system was part of the issue. In this engine, the computer uses engine oil and a solenoid to shut down the engine lifters on four of the cylinders during certain situations to save fuel and improve emissions. In actuality, it turns an eight-cylinder engine into a four-cylinder engine. The computer also will shut down the corresponding four fuel injectors. We found when we used the scanner to manually shut down the system, the loud noise went away. What a difference from the old 1941.

We were using computers to talk to other computers to diagnose internal engine systems. We had not experienced this in the past and I hope we will never forget this one either. Fixing cars is a lot like the rest of life. We live and learn from our experiences. Hopefully, we don’t forget them. I Hate When That Happens!

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Written by Randy Gerdin on February 1, 2017

Our staff and I have been working on cars and truck for many, many years. More often, it seems we look at each other and just say, “Crazy”. Of course, we are referring to the technology of vehicles and what it takes to repair them. Recently, we had a full size major brand pick-up into the shop. The complaint was a check engine light and occasionally the truck seemed not to shift properly. The owner also had purchased a couple of non-factory key fobs off E-Bay that he wanted programmed. We started in, scanned the computer with the factory scanner, and found 4 codes all relating to the oxygen sensors and their circuitry. We took the vehicle on a 10-mile test drive while monitoring the oxygen sensors, as this vehicle has 4. While driving, we did not notice any issues or irregularities with the sensors, their response time, or any other issues.

When we got back, we opened up our on-line professional database/repair manuals, did our research, and found that this vehicle had a program update available for this condition, as well as a transmission update. The repair manual instructed us to perform the update, clear the code, and test drive. If the codes stayed cleared, that would be all that is needed. If the codes returned, the Power-Train Control Module (PCM) computer would need to be replaced. In addition, the manufacture had released a recall on the PCM for this issue. That is great. However, we needed to go through those steps to verify what needed to be done. In fact, after the update to the PCM, the codes returned and we informed the owner of the recall, which he should have received in the mail.

We then started to program the key fobs. The first step was to replace the batteries in the fobs, because they were dead. After we replaced the batteries, we then did the reprogramming sequence. When done, we found the vehicle would start, but the door lock-unlock did not work. We then, with our factory scanner, went into the body control module and monitored the lock-unlock signals. We found that the computer would recognize one of the fob signals, but not the other. Also, the locks would not actuate on the truck. We could use the scanner and lock and unlock the doors, but the E-Bay fobs would not work. That is one big risk with getting aftermarket keys/key fobs. There is just so much security built into these vehicles. Without this security, someone could pick up used or aftermarket fobs, program them, and in essence steal anyone’s car. Crazy!

We encountered another technical challenge a few weeks ago while installing a remote start system on a 2016 vehicle with a push button start, no real key. We went through the entire installation, and at the end found out the remote key fob had not been properly programmed at the factory to allow the remote start system to activate. The owner needed to take the vehicle and key fobs back to the dealer and have them reprogrammed. At first, the dealer did not understand what needed to be done until after our technician spoke with the dealer technician. They did what they needed to do, returned the vehicle, and we finished the install and programing. Once again, “Crazy!”

I regularly spend time reading technical journals regarding what new technology is coming out. Again, I say “Crazy”. Technology is moving at an increasingly rapid pace. My concern is, what happens when these vehicle are ten years old or older? I feel we don’t know what is going to happen with this technology. But as always, each day is a new day of learning. One unfortunate consequence is it seems that all this new technology can come with an increase in price as well as a steep learning curve for the consumer. I Hate When That Happens!

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You won’t do what?

Written by Randy Gerdin on August 1, 2016

This month I would like to touch on a subject that is very “touchy” with some folks. This scenario happens once or twice a month, and sometimes people are not happy about it. When I speak with other shop owner I know, they all agree it can be a problem if you do and if you don’t. Most don’t. So, what’s the big issue?

This may come as a surprise to some, but the issue is we periodically have a client who would like to supply their own parts to fix their vehicle. Of course, the main reason they do this is cost. Most reputable shops will never allow someone to supply their own parts. Most shop owners are very particular about which brand of parts they use. Even within a specific brand, there are different part lines to appeal to many segments of the market. In other words, one tie-rod end may or may not be the same as a different brand of tie-rod ends. Even if you go to a dealership to get your vehicle repaired, they also have different part lines for the price conscious buyer. They are not the same as the ones that came on the vehicle from the factory. Also, the part you buy from the manufacture may not be the highest quality. There are many aftermarket manufactures that produce parts that actually exceed the quality of the original equipment items. I guess summing this all up, automotive parts are not a commodity per-se.

Back to the original subject, why most shops will not install customer supplied parts. One reason is to protect their own reputation. If a particular repair would fail, it may be misconstrued as the fault of the installer, when in fact it was an inferior part provided. Professionals also know from experience what brands of parts work well with certain vehicles and what brands do not. For example, we have found a certain well-known and high quality spark plug does not perform well with a particular vehicle. We also have learned that, in some cases, unless we go back to the vehicle dealer (even though it is much more expensive) for a particular item, the vehicle will not perform well. For most things, aftermarket parts have exceptional quality at a greatly reduced price. However, we have found better pricing at the dealer level for certain other items. That is one reason people choose to pay a professional for their services. Professionals are professionals.

One case in point, we have a commercial client who had been working on their own vehicle and the repair became more complex than they had planned. They had already purchased the part, and because of a long time personal relationship, we broke our policy and agreed to use the part they had purchased. We installed it and the vehicle would not start, so now what? Was it something we did or a problem with the part? We ended up diagnosing the problem as a failed part. The client took the part back to the parts store and they gave them a new one. We installed it, and low and behold, we had the same scenario. So again, after much time spent, we found the part to not function again. This part was an electronic part with no moving pieces, just circuit boards. We got our diagnostic hotline involved and they agreed with us. We then started researching the part number they were given. Low and behold, we discovered that they had been given the incorrect part. According to the part supplier, the part was correct, but in fact it was not. We secured the proper part numbered part, installed it, and the vehicle started right up. This was a very frustrating situation for the client, the part supplier, and us. I do believe that we would have gotten the correct part number the first time because of the methods we use to source parts.

Another reason most shops will not install customer supplied parts is that a repair shop is a business, and the parts revenue is one way that the company stays in business. I know one would not walk into a restaurant and bring their own steak to be prepared by a professional cook, because they feel that the price the restaurant charges for the steak is too high. All businesses survive, thrive, grow, and innovate based on their profits.

The final reason to let your professional shop supply the parts is in case of a part failure, you have the company’s warranty to stand behind the part they supplied. If you supply something and it does not work out, everyone loses. I Hate When That Happens!

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