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Mark Gittelman is an ASE Certified Master Technician With more than 28 years experience in the automotive repair business. His friends call him MasterTechMark, but you can call him your personal auto repair business insider. For more free automotive information visit his other sites at and See Mark’s Auto Repair Credentials and Work History on Google+.

The website was built to help the do it yourself driveway warrior looking for supporting information about certain car problems. These in-depth articles are also useful for retail automotive service consumers as they try to sidestep extra charges and unnecessary repair operations. With over 200 pages of original content the site relies on the top navigation to narrow things down for visitors.  Also available are the custom search boxes found below and in the sidebar.

1979 Pontiac TAMark is not only a Professional Mechanic, but remains an active hobbyist and a big fan of motorsports. He’s built several track tested performance cars and enjoys competing on street night at the local drag strip. He’s managed a few show worthy muscle car projects as well. Two of his biggest loves was his precious 1979 Pontiac Trans Am with the Mighty 6.6L V8 and the shaker hood scoop. Although domestic cars were always his strong point he branched out in the 90’s to include a 1988 300zx to his collection. This car was nicknamed Christine, because of it’s ability to draw blood from those who worked on her. You can review some of the repairs she needed on the Nissan 300 ZX section.

If you need auto repair information right now and would rather bypass the hunting and searching you can ask your question on the auto repair help page on my other site. Your question will be posted to a premium car repair forum that is monitored by tested professional Technicians. There may be no better or faster way of getting the answers you need for specific automobile solutions from an actual expert. Reply times vary but researched answers are usually provided within 15 – 30 minutes of submission. Of course on Holiday’s and weekends it might take longer?

15 Replies to “About”

  1. Jesse

    I just read through your whole book, and I’m most impressed with the negotiation section right in the beginning. I’ve worked in the computer service industry for my entire career, and the two industries share many many unethical practices.

    You kept your negotiation section clear and focused, without turning the reader into a nagging “isn’t there a cheaper way?” person. That’s an important point to make, since annoying nagging customers will receive different service than a customer who demands reasonable quality at a fair price. It’s a hard line to follow, and while your scenario does a great job at that, I feel that it’s worth pointing out.

    Thank you for publishing your book. I’m sure you’ve received a lot of negative feedback from shops, but I can honestly say that seeing this book on the counter of any shop would make me feel more at ease going there with my own vehicle.

  2. kim

    Hello, I found your website through a google search. I recently have started working at a Auto Mechanic Shop in the office. I know nothing about cars. LOL Quite funny that I would find myself in a job dealing with cars. I was looking for information about cars just to get familiar with the terminology etc… The work I do is writing up work orders after the estimate is written, ordering parts, answering phones, accounting etc… I have really enjoyed your website and find it easy to understand. Thanks.

  3. Matt

    I read most of your book. I have to say I really like the way you explain things. I did own one of the few honest shops in my area for years and I hated trying to compete with the many ripoff shops out there. My only advantage was my love for diagnostics which led to many new customers after I could usually fix what other shops could not. This led to many for life customers. Never the less I talked many customers out of repairs because I felt that the car was not worth investing money into.

    There was one thing I have to strongly disagree on. It is in regards to brake flushes. I never pushed anything on any customers, but this is something I like to keep up with even on my own vehicles, so I always recommend it with a 4-5 year old vehicle. Not because of the corrosive properties of brake fluid which like you said the majority of parts will still last life of the vehicle. It is because of the brake fluids hygroscopic qualities that increase the brakes tendency to fade as moisture is absorbed into the hydraulic system over the years.

    Now the majority of time even if the brake fluid is very old and has collected large amounts of moisture it will still brake on command because in most cases the brakes do not get that hot. But what about the hot day where someone is going up down hills braking very hard and then a car pulls in front of them and they have the temperature of the brake fluid right at the boiling point because the moisture that has accumulated over the years. I do not want to have my children in that vehicle just like I do not want to talk my customer out of a brake flush just because that scenario is probably unlikely in most cases. So for the $100 I think the brake flush is a wise investment every 3-4 years especially in any kind of harsh driving conditions.

    Now some make the argument with modern brake systems they are sealed so well there is no need, but again I think the risk is to great and even with modern systems moisture usually finds away into the system over time. I think it is similar to fixing the air bag when the light comes on. 99% of the time we will never need it, but when we do we will be glad we have it. Furthermore with any tow vehicle or performance vehicle I think it is a absolute must and can make a argument about flushing the system every 1-2 years.

  4. Mark

    Matt: I agree with you 100% on your statements about the brake fluid being hygroscopic. And maybe my point was not made clear in the book. I’m hoping to expand and edit the book soon and will pay close attention to that section. My jaded opinion was formulated from seeing the brake fluid flush service sold as a profit center as opposed for genuine safety concerns. But your point is well taken!

  5. Glenn

    Mr. Gittelman: I am basically 100% auto repair ignorant. I have worked with the automotive industry for 18 years, but still barely know how to change my own oil! I came across your website and your book today, in an effort to better understand the Auto Repair Industry, as related to my field of marketing. I just wanted to take a moment to thank you.

    I read your book from cover to cover, and I found it engaging, informative and honest as well. I do, in fact, have a mechanic that I feel is the “Golden Egg”…one who performs his his craft with a smile on his face, and brings smiles to his customers as well. However, your book has given me an invaluable insight into your industry. Not just the negative, but also the positive.

    You represent your profession well. As I read through your book, website and blog, I kept waiting for the salespitch. However, there was none. Apparently you have done this for the same reason my mechanic does…because it brings personal satisfaction. I sincerely thank you, and commend you as well.

  6. Josh Besso

    I just wanted to take a moment and praise your efforts. I feel you are truly one of the very few people out there that truly know what they are doing. I enjoyed reading your posts and by other comments I can tell it is very common to hear what an outstanding job you do. Thank for keeping me in touch with the automotive world..

  7. John Eichel

    This is actually a question, but submitting it here because it is really not a “car question” per Se. Am thinking seriously about buying an auto repair shop, and looking for advice regarding what to look for. Am 58 years old with a career in business, so that part I probably have covered. Have also been an avid DIY over the years when it comes to my own vehicles, so am mechanically inclined and interested in the subject area. Shop size is 4 or 6 bay, with a handful of full-time technicians. Cincinnati, Ohio area. Are there a top 3 or 5, etc, things an experienced owner of a shop would be looking for? Location is surely one. How do I evaluate the competency of the technicians, for example. Do I try to determine the reputation of the shop in general? How would I go about that? Any other advice you might be able to provide would be very helpful. I’m all about due diligence, and this seems to be in great need of it.

  8. Mark

    John Eichel: I really can’t provide advice about buying an auto repair shop because I have never done so. It’s the kind of business in my opinion that has so many things stacked against it, it’s hard to find any positives. With that said my opinion is most likely jaded. I think an established customer base is one of the most important things. Talk with these loyal customers about what they think are the weak spots of the business. Read comments from this page

    Some shop owners stopped over there to comment and you can get an inside look at just one of the details involved with the business. Also some of them provided links to there shops websites so you could speak to them more.

  9. Angela Stringfellow

    Hi Mark,

    I work with Direct Capital, an online lending agency providing small and mid-size businesses with fast, easy access to the capital they need to grow and prosper. I wanted to reach out and let you know that we’ve just released our list of “Top 50 Automotive and Mechanics Blogs: The Best Industry Blogs on Auto Technology and Auto Repair,” and you’ve made the list.

    Congratulations! You can see the full list here:

    It would be great if you’d share this news internally and/or with your audience on social media. You can find us on Twitter @DirectCapital

    Thanks so much for your time, and congratulations again!

    Angela Stringfellow

  10. Tom

    2010 Equinox, 2.4L; was doing some maintenance (bleeding brakes, nasty dirty fluid) the other day so thought I would pull the throttle body to clean it up while I had the engine cover off since I was also looking for the EGR to see if all connections looked good (turns out this engine doesn’t have EGR).

    Was able to unbolt the TB but couldn’t unplug the pigtail so I cleaned the throat while attached to pigtail (electrical plug was not yanked on). Yep, throat was black, used a little carb cleaner (did not spray indiscriminately) and rags/paper towels to clean black off (inside the TB throat only). Was careful not to damage green gasket ring to intake on removal or replacement. While cleaning the TB throat with plug attached I was moving the butterfly valve open/close to reach all areas to wipe. Re-mounted everything and now it runs …terrible.
    Acceleration off the line is bad (it misses and stumbles), it hunts for gears, doesn’t shift right, once up to highway speed it drives acceptably. OBD reader shows P0223, Sensor/Switch B Circuit High Input. I tried clearing the codes and starting engine back up, immediately generates the same code. I started this morning and now it literally sounds like a motorcycle idling and then dies after about a minute.

    Mechanic friend of mine says it sounds like the IAC may not have been cleaned but I had already tried pulling the side cover off (after finally figuring out how to unplug the pigtail) and could not get it to pop apart. Only thing I can think to do now is to replace the TB with a new one (which comes with IAC attached), but I would hate for that not to be the problem and spend money for nothing.

    I could try testing the pigtail for connections but would have to know what kind of voltages and signals to expect. Ideas?

    • Mark Gittelman

      Tom: There’s no question that the throttle body is a weak link on the equinox and the code you set is often associated with a problem requiring replacement. However there is no guarantee it will solve all of the problems you described. If you order the new TBI from amazon you could most likely return it if you had to. equinox 2.4L Throttle actuator

  11. Tom

    Thanks Mark! I ordered the TB from Amazon before your response, arrived and installed it yesterday (hated to spend the money but not much choice). Once I let the ECM reset by pulling fuses for 20 minutes then reinserting them, and then by leaving it in the Run position without starting for another 5, it fired right up witha slightly rough idle. Service StabiliTrak light immediately out, CEL still on. Drove it around the neighborhood, cautiously optimistic. Had to clear codes with OBD reader. Drove it to 15 miles to work today during a light rush hour and can begin to feel it settling in with smoother idles.

    …give me a 400 SBC with Quadrajet any day over this unable-to-fix drive-by-wire electronic junk. almost impossible to work on this stuff without a $20,000 piece of equipment.

    As for your website, keep it up! I’m a gear head that can fix it once shown or told how, even though my real profession is I.T. Systems Analyst. You give enough information that explains HOW to fix, WHY it broke, WHAT ELSE to look at, etc. Outstanding! My ’65 Impala SS convertible, ’67 Impala convertible, and ’86 El Camino Conquista say “Thank You!”

  12. Charles McCreary

    Hey Mark, I just wanted to point out that many libraries have “Mitchell on Demand” that patrons can use at no
    charge. ex library employee and backyard mechanic, Charlie

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