Goss's Garage

Pat Goss
Automotive repair expert
Thursday, March 20, 2008 11:00 AM

Pat Goss has worked on cars for more than 40 years. He owns a car repair company that bears his name, has authored numerous books on auto maintenance, and makes weekly appearances on Motorweek, a PBS television program.

He visits right here once a month to answer questions about fixing your car.

For more auto advice and industry news, visit our Cars section.

The transcript follows below.

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Crystal City, Va.: What is the long term repair record like for the old 300M that was based on the Intrepid?

Pat Goss: The major parts are quite good but as these cars aged they had numerous small but expensive and annoying problems.

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Waldorf, Md.: I am trying to find a cheaper diesel car. I do not care what type of car it is just diesel. But all search engines will only do it by make, not by engine type. Do you know a search engine that will do by engine type?

Pat Goss: Unfortunately no. But websites like Cars.com can get you close. Your searches don't have to be that detailed as there are only a couple of possible choices anyway.

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Denver: Jeep Grand Cherokee 2006. Does a dealership have to do the 30,000 mile service to keep the warranty in good standing and what service should I have done?

Pat Goss: You should have every last item described in the owner's manual done and it can be done by any qualified person --- even yourself --- if you're qualified. But you must use proper products and keep records.

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Washington, D.C.: Pat, hello from northeast Washington. My 2004 4.8L equipped Silverado came with iridium spark plugs that are supposed to be good for 100k miles. Should I expect them to last that long? I'm at 75k right now and so far everything seems to be working well. Thanks for all your good advice over the years.

Pat Goss: We find many that go twice that long. Usually I recommend waiting until there is a symptom that suggests they need to be checked.

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Fairfax, Va.: BMW announced a new "double clutch" transmission in their M3 model. Can you explain how it works and what are the benefits?

Pat Goss: Sorry but not enough time or space here. But it is nothing new and has been used in other segments of the automotive field for years. They normally give better clamping forces to deal with higher horsepower and torque while maintaining low and smooth pedal effort.

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Baltimore: Pat: What is your take on so called "clean diesel" that has become a major alternative to gasoline vehicles in Europe and is set to come here? Do you think it can challenge hybrids, or will the old perceptions of diesel (good mileage, but noisy and smelly) hold it back? And will technicians need retraining to work on these drive trains? Thanks.

Pat Goss: If people drive one of the modern diesels they will immediately realize noisy and smelly no longer applies to diesels. They will also see that performance is amazing. The best of all worlds is diesel hybrid.

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Edgewater, Md.: Pat, my car is at your shop as we speak for some routine maintenance... but here's my question: I have a fairly long commute to and from D.C. into Maryland near Annapolis, and my paid-off 04 Solara gets me an average of 25-27 MPG. With gas prices climbing toward $4 a gallon, if I got $10k on a trade and paid $23k or so for a Prius that gets 50 MPG (my brother commutes to Baltimore in one and gets that much every day) is it worth it? I usually keep a car forever which is why I take it to your place, but cutting my gas bill in half seems very attractive. Also... got the bike out yet?

Pat Goss: I have never been a fan of hybrids from the standpoint of payback through fuel savings. In the past gas prices didn't make that a reality. But now that gas is over three dollars per gallon they begin to make sense for those of us who drive a lot. My fuel bills had climbed to over five hundred dollars per month on my twenty mile per gallon cars so a week and a half ago I went to Annapolis and bought a Prius. At the fifteen hundred mile mark it looks like I will save three hundred and fifty dollars per month. Lots of driving, they make sense a little driving, they make sense for the enviroment but not for the wallet.

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Laurel, Md: I use my cruise control quite often. I feel as if I am getting better gas mileage. I also invested in a dual tire inflater with a gauge. Two air lines that enable me to put equal pressure in both tires without guessing if they are the same. Your thoughts?

Pat Goss: For many drivers cruise will provide better fuel economy. Whether it does or not depends on how steady you are with your right foot. I have seen a couple of the multiple tire inflators that are accurate but I would never trust my tire pressure to anything but a high quality tire gauge.

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Takoma Park, Md.: I am used car shopping under $3K. First... I am surprised how few manual trans car are out there. I am looking at a 1993 Sentra with 120k on it. My friend had an SE-R version of the same car and his had problems with the trans popping out of gear. Says it was a problem with all Sentras. Was it all Sentras or just the S-ER version, did that come with a different trans with limited slip or something?

Pat Goss: Most Japanese designed manual transmissions have a history of poor performance. We see a lot of manual transmission cars in a years time that pop out of fifth gear due to internal wear.

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Alexandria, Va.: Pat, I will be purchasing a Silverado 1500 and they offer a 5.3l in aluminum or iron block. Which one and why? I assume the aluminum block engine is lighter, but what about reliability/longevity? I intend to have this truck 7-10 years. Thanks.

Pat Goss: Both are very good but more than aluminum or iron I would look for fuel management. The fuel management system gives great performance with significantly better fuel economy. I believe you will find fuel management on the aluminum engine.

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Tampa, Fla.: Hi, Pat. I recently took my 2004 Corolla in to get the A/C looked at as it quit blowing cold and was told that the compressor is not getting any power to it. Any ideas on what the cause may be and is this something I should attempt to repair or would I be best taking it to the dreaded dealership? Thanks for your help.

Pat Goss: Dreaded dealership? Maybe maybe not! What you do need is someone who knows air conditioning day care. Usually if the compressor isn't getting power it indicates low refrigerant in the system. Step number one should have been to use a refrigerant identifier to check the system. This tool would have shown the percentage of refrigerant, air, etc. Had this been done it would normally show a high concentration of air which would cause safety devices to shut down the compressor to preserve it. Of course there are lots of other possibilities but low refrigerant is far and away the most common.

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Palos Verdes Peninsula, Calif.:1994 Jaguar XJ6 four door sedan ...

Problem: At times the interior floorboard of my car gets very hot. Both front and back seat interior floorboards.

The first time I noticed it was on a trip from Calif to Colorado. It has since happened after about 10 miles of freeway driving at speeds of about 60-75 MPH. Another time was on a trip to Las Vegas.

The floorboards and interior of the car get very hot.

I've gone to several mechanics and no one can tell me with any degree of certainty what is causing this.

Pat Goss: Begin by checking the positioning of the exhaust system and condition of exhaust system shields. If all is in order it may be normal for the car. If it is normal and it annoys you it should be possible to have a good custom exhaust shop fabricate heat shields to isolate the heat --- somewhat!

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Montgomery Village, Md.: Pat, it seems that years ago, we were encouraged to periodically put a "gas drier" in the fuel tank to remove moisture and/or water from the fuel system. Was this all hype? Did it really work? Should we still do it? Would it hurt the fuel injectors that so many vehicles have now? Or just hurt our wallets? I drive a 2005 Acura TL. Thanks as always for your sage advice.

Pat Goss: It has always been a good idea but since the advent of ten percent ethanol in our fuel it is almost mandatory. Ethanol attracts moisture which makes fuel system damage more likely than ever. But there are two types of "dry gas": methanol and isopropyl. Use only isopropyl products as methanol will only prevent freezing, it will not help get the moisture out of the tank. Use one twelve ounce bottle once every month.

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Waldorf, Md.: Is there a spray that will help get what looks like dust particles off a windshield? I have tried several things and nothing seems to work.

Pat Goss: I use glass polish from Griot's Garage. I have been very pleased with the product's performance over the years.

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Gaithersburg, Md.: Pat, I have a 2004 Infiniti I35. Ever since getting the car in 2005 (Used 11k miles) there is a pinging (or knocking?) around 1800-2000 RPM's. I've expermented with all different grades of fuels per the dealer and have used numerous treatments of BG44K to no avail. The dealer tells me that it's not uncommon with this engine but I think they just don't know what the cause could be. I've researched a bit online and found that it could be the mass airflow sensor or the knock sensor. What are your thoughts? Appreciate the help!

Pat Goss: Mass Air Flow is extremely common and very easy to check. Also we see a lot of Nissans with bad knock sensors and again an easy test. Finally if the car has EGR that should be checked as well but remember the entire system must be checked not just the EGR valve.

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Baltimore: I have a 2000 Mazda MPV. The dreaded "check engine" light came on and my shop is telling me that I need to replace the oxygen sensors at a total cost of over $1,000. Is this a repair that I can defer?

Pat Goss: It would be highly unusual for all the oxygen sensors to go bad at once. Of course anything is possible but it is nothing I have ever seen except through external damage. Also did your shop actually test the sensors or are they making the recommendation based on codes? We often find shops that do nothing but read codes and recommend the parts referred to in the codes. Codes unfortunately do not tell what is wrong only what is being affected by what is wrong. For each code there is a test with the same number that has to be performed to find out what is actually wrong. The most common cause of oxygen sensor codes are vacuum leaks and lean fuel mixture not the oxygen sensors.

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Anonymous: Mr. Goss: I have had my car in the Acura repair shop three times in the past week. They can't seem to identify the source of a terrible belt noise. I have had the pulley and pulley belt replaced and also some other belt that was worn out. I'm not sure what to tell them. I have begged them to leave the car alone for three to four hours and then start it up and listen for the sound. Short of that, any ideas of what I can suggest they do? I am frustrated. The dealership service department is top notch, but this little issue has been a headache for all of us. I would like to think my 2003 RSX shouldn't have to make this noise. Thank you!

Pat Goss: They need to check: belt alignment, belt tension (belt tensioner,) and for contamination on the pulleys. Further they should be checking to make sure none of the accessories driven by the belt are too hard to turn at startup.

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Anonymous: To V-Chip or not to V-Chip? Hi Pat -- I enjoy your chats and you give great advice! I have a 2003 Hyundai Sonata. I like it but hate that I bought the slow base model. My brother suggested a V-chip that will give me more horsepower. Are these things safe or will I completely ruin my car? Thanks!

Pat Goss: No they will not hurt your car but they can make you fail your emissions test and don't expect miracles. There are legal chips and illegal chips. Legal chips can only change settings at absolute full throttle so the only time you would see a diference is when your foot is on the floor. Illegal chips can change the operating parameters throughout the performance range of the vehicle. But what you feel, if anything, will be very minor. Most such devices have meaning at the track where a thousandth of a second can make the difference between winning and being the first loser.

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Rockville, Md.: Hello, I was wondering if you knew where in the Rockville/Gaithersburg area I could purchase BG44K? Thank you.

Pat Goss: I'm afraid not but if you go to www.bgfindashop.com and enter your zip code you will get a list. You can also call them at 800-327-8883.

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Bethesda, Md.: Hi Pat... I have an '04 Volkswagen Phaeton out in Scottsdale, Arizona and want to put new tires on it. Should I stick with all-season tires or just get summer tires (if there's such a thing?) Thanks.

Pat Goss: In Arizona summer tires should do fine. But be careful as many summer tires are now directional which means they can't be properly rotated and that often makes them get noisy early in life.

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Reisterstown, Md.: Hi, Pat. I use Bon Ami cleanser to polish my windshield. It cleans off the grime and that oily residue you get driving during the rain. It's made of feldspar and will not scratch glass. Sprinkle a little on a damp paper towel and rub over the surface of the glass. Allow to dry, then polish off with a dry paper towel. I can't always find glass polishes but I can always find Bon Ami.

Pat Goss: I used Bon Ami for years and recommended it until it became hard to find in many areas. I then tried the catalog glass polish which wound up being less messy and does as good a job. But if you can find the Bon Ami it is a good and MUCH cheaper way to get rid of windshield film.

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Minneapolis.: I have a 1990 Camry that is still running well, but is getting water in the trunk. Is this water a major problem, or a minor nuisance? I'm worried because of the water sitting in the spare tire well more than anything, and that I think the car is rusting from the inside out.

Pat Goss: You're right about the rust. Often we find the spare wheel, jack, and tools rusted so badly they aren't safe to use. Also over time the body of the car will succumb. But in most cases the fix is easy. If you open the trunk and look at the forward corners of the body below the rear window you will find a seam in each corner. These seams are caulked at the factory to prevent water intrusion. Over time the caulking becomes brittle and flakes off. Usually the leak can be fixed by cleaning and re-caulking those corner seams.

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Washington D.C.: A few weeks ago my '98 buick Regal GS spontaneously combusted in a Metro parking garage. The fire destroyed my car and damaged five others as well as the garage. I got a paltry settlement from my insurance company which was not nearly enough to buy a replacement car, so my out-of-pocket expense was consdierable. Last Friday Buick announced a recall for this problem, saying there had been over 200 cases of fires. Since GM has obviously known about this for some time, do you think they should be liable in some way? Can I get a new car or something from them?

Pat Goss: A new car would be out of the question in most cases. After all recalls and settlements are not a lucky day solution but rather a solution to make the vehicle owner safe or whole again. In this case you MAY be entitled to something based on the recall. But that something would usually be the difference between the insurance company settlement (if the insurance company was realistic and didn't get you to sign off for a bogus amount) and the true value of the car plus some inconvenience. But there are a lot of legal issues involved and I am not an attorney so I would discuss it with an attorney familiar with automotive affairs.

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Florida: Hi, Pat--Lots of useful advice today. Down here we have both ethanol and humidity just about year-round. I'm going to start using the isopropyl, but what can result from moisture in the gas tank? Thanks!

Pat Goss: Moisture in the tank can cause de-plating of metal tanks, rust inside metal tanks, fuel pump failure, performance problems, rusted fuel lines (if made of metal), check engine light illumination, damage to fuel injectors, etc., etc.

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Fairfax, Va: I rented a diesel Mercedes-Benz in Germany a couple of years back and was amazed. No fumes or excess noise, great fuel economy, very nice performance, and diesel fuel was cheaper than gas. Unlike here!

Pat Goss: Yes we just don't seem to get it. I love diesels but had to get rid of mine due to the cost of fuel. I do a lot of driving and because diesel is so high in the US my cost per mile was higher at thirty miles per gallon of diesel than at twenty miles per gallon of regular gas. RIDICULOUS!

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Montgomery Village, Md.: Dry Gas question follow up: Thanks for your earlier answer. Since I have never put "dry gas "in my 2005 TL, with 74,000 miles, might I expect some kind of indicator light to pop up because of the different "burn" of this product? I always use 93 octane premium gas.

Pat Goss: No! You're only using twelve ounces in a full tank of fuel so there would be absolutely no difference in how the fuel burns or how it affects any of the sensors.

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Gaithersburg, Md.: I have an 04 Acura TL which I'm very happy with. My mechanic, who has never steered me wrong has recomended I get my transition flushed every 10,000 miles due to issues with Honda/Acura transmissions. It's not that expensive to do, so I don't have a problem, but I was curious if that was normal. Thanks!

Pat Goss: Honda has had some serious transmission issues so flushing is a great idea. However I'm not sure about every 10,000 miles. I normally recommend two years or twenty four thousand miles and use a high quality fluid. That would be my recommendation for all cars.

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Arlington, Va.: I have a rotary engine and I get a lot of noise when my manual transmission does not have the clutch pedal depressed, however it is noticeably less when the clutch pedal is depressed. What is the likely problem and repair estimate?

Pat Goss: If applying very slight pressure on the pedal makes the noise lessen you probably have a bad release bearing but if the clutch has to be completely released it is most likely in the transmission.

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Leonardo, N.J.: Hello Pat. My 1994 Mitsubishi Eclipse seems to go through oil pretty rapidly, forcing me to give it about half a liter every 200 miles. It has zero leaks so I know it has to be burning off but I don't have the faintest idea of how best to service this problem. I have always been diligent with tune-ups, replacing sensors, and etc. What would be likely culprits for this older engine, or is it to just to be expected with over 160K on it?

Pat Goss: Not expected on most engines but Mitsu had a history of problems on their older models. In most cases it was bad valve seals but on some we found stuck or worn oil control rings on the pistons. But no matter what the cause it really wouldn't make sense to open an engine with that many miles. Keep it topped off and run it to failure. Spending money on a major repair would move you from being ahead of the curve to seriously behind it. Not smart.

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Richmond, Va.: We recently purchased a used 2002 Audi A4 3.0 liter (not quattro.) It's due it's 80,000 mile service in a few months. Do we take it to an Audi dealer or will any euro automotive place work? I realize the dealer would probably be more expensive but would we be getting any better analysis/tune up? I believe it's timing belt time as well. Thanks!

Pat Goss: That completely depends on the skills of the dealer and the skills of your independent. There is no guarantee that a dealer technician will do a better job. If you one of the top techs in the dealership you'll be okay but if you get the "new guy" who knows? But that's exactly the same at the independent. It isn't the name over the door as much as it is the skills behind the door.

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Arlington, Va. On a rare occasion my manual transmission 2000 Ford Focus ZTS (subject to frequent problems, I might add) revs at 4000 RPM at idle (the car also appears to be trying to idle that high when the gear is engaged, but is restricted by the gear?) It eventually stops after 20 minutes of driving or being parked for awhile. What should I ask the garage to look into?

Pat Goss: Check the idle air control (IAC) for varnish buildup. If the IAC is clean check it's function and if it passes these tests check the signals being delivered to the IAC.

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Pat Goss: Well folks I guess it's about that time. Thank you for participating, I really appreciate it! Until next time please remember and support our troops and please --- Drive Gently! Happy Easter.

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