James and team did a great job getting my wife's a/c up and running before summer. James diagnosed and explained every part of the repair, gave me options and never pressured us. I have already given his name to several friends. We would definitely use again. read more

Responded very fast and point out which issue I have Unfortunately my issue was a major one they couldn't handle. I did some major research. But Thxs to them it made finding the issue and getting the parts easier and less headache for me. I highly recommend them for diagnostic and minor fixes. I would hit them up again for all my cars issue if I can't figure it out myself. The car is question was 2015 Chevy Tahoe misfiring Issue was map sensor and AFM read more

I hired this mechanic to replace the cinching actuator on my Tesla. Immediately after he completed the work, my car began making loud, abnormal noises that never existed before. My door handles started making a loud squeaking/horn-like sound. When I opened my trunk, it sounded like it was malfunctioning or "dying." The same noise occurred when the trunk closed. When I opened my doors, the noise came from the trunk again. Even when I backed into my driveway and pressed the brakes, my car made a loud honking sound. All of these issues began after his repair. I contacted him immediately to let him know something was clearly wrong. Instead of taking responsibility or offering to inspect the problem, he became defensive and accused me of lying. He claimed the issues were preexisting and said I had tampered with my own car. He talked over me, became argumentative, threatened to cut business ties, said he would block my number, and abruptly hung up on me. He also blamed me for "self-diagnosing," even though I was simply describing the symptoms I was experiencing--something any customer would do. I hired him because he is the mechanic. It is literally his job to assess, diagnose, and fix problems. Instead, he refused accountability and demanded I pay him an additional $250 just to run a diagnostic to determine whether he caused the problems. Every reputable mechanic I've worked with in the past has stood behind their work. This one did not. He then sent me a disclosure form he wanted me to sign stating that I would only receive a partial refund if he decided the issues were his fault. I did not agree to this. When I didn't respond to his repeated messages, he texted again saying that after "some thought," he would now be willing to refund only a "portion" of what I paid. I paid him $350. When I declined to pay the additional $250 diagnostic fee, he argued with me and repeatedly stated that because I said no, I was "accepting that this is the end of the issue," then hung up on me. To document the abnormal noises, I opened and closed the liftgate several times. During this process, a panel that concealed the wiring fell off its hinges. A Tesla-certified mechanic later told me this was because the panel had not been screwed in correctly. I ultimately had to hire a Tesla-certified mechanic to fix what was done. Based on the symptoms I described over the phone, he immediately recognized that the wiring had been done incorrectly. When he inspected the vehicle, he confirmed that multiple connectors were improperly rewired, including the liftgate being wired into the speaker system and the trunk light being wired incorrectly. The horn was sounding as a warning that something was wrong. This was not only careless -- it was a safety concern. This mechanic was rude, dismissive, unprofessional, and completely unwilling to stand behind his work. Based on my experience, I would strongly caution Tesla owners and anyone with a modern vehicle against using his services. *** This is in response to Jane's response. PLEASE READ as this is very important. James claims he offered a "warranty check," AKA "diagnostic," but only if I paid him an additional $250 for his time. I declined. At that point, he repeatedly talked over me, read a disclaimer aloud without allowing me to respond, and ignored my polite requests to speak. He then told me he was "ending this relationship," said he would block my number, and abruptly hung up on me. He did not offer a full refund--only an unspecified portion of what I paid. I uploaded a photo of the revised invoice he sent after damaging my vehicle. In that invoice, he attempted to insert a disclaimer stating that I would accept a partial refund only after he decided whether he caused the damage. The document does not specify any refund amount. Had I signed it, I would have forfeited my right to a full refund. After my Yelp review, I sent James videos from a Tesla-certified mechanic explaining exactly what he did wrong. He incorrectly reattached the wiring, connecting the liftgate to the speaker system, which caused the loud horn noise. On a Tesla, this sound is a safety alert indicating faulty electrical connections. James presents himself as an honest professional. My experience was the opposite. I was spoken over, yelled at, threatened with being blocked, and treated with hostility when I simply asked questions about the damage done to my vehicle. I have never been treated this way by any business before. Based on both his conduct and the documented mechanical errors, James is not qualified to work on electric or modern vehicles. His behavior was unprofessional, aggressive, and manipulative. I strongly recommend that anyone with a newer or electric car take their business elsewhere. Quantum Mobile Mechanic is not on Better Business Bureau. I reported him to the BAR (California Bureau of Automotive Repair).*** read more

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Looks like their 5 star quality reviews continue with me. From start to finish, the communication was easy, the tech was informative and the quote and price was as mentioned with no hidden fees. Their availability for same day service is what hooked me but the overall experience is what will keep me coming back. The entire process felt genuine and honest, hard to find in an industry with shady mechanics so this was refreshing. No upsell or "discovery" work. Thank you for the service. read more

My main concern is that Quantum Mechanics communicated their assessment directly to the dealership and did not properly inspect the vehicle, even though I paid for the inspection. The assessment they gave the dealership described the car as "well-maintained with a few minor issues," which contradicted what I was told: the car needed its power steering fluid changed, new suspension struts, ball joints, engine, and transmission mounts, totaling $2,676.35. Because Quantum Mechanics called these issues minor, the dealership remained firm on its listed price. I don't understand why Quantum Mechanics communicated this directly to the dealership, since I paid for your service, not them. Also, the car had many other issues that they did not mention, like rust, the floorboard, and the dashboard lights. The e-brake sometimes does not engage it also has an oil leak read more

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This was a very easy and pleasant experience for me. Having a mechanic come out very quickly and taking care of my alternator on a Saturday meant I did not have to take extra time off during the week to have my vehicle towed and repaired, hopefully the same day. Service was quick and efficient, and the mechanic had a great attitude. Will definitely be reaching out the next time I need mechanic assistance. Pricing was also very reasonable! Thanks James and Jacob! read more

Great experience, great price. He was professional and was able to help me out same day. Will definitely use again read more

I found James on Apple Maps for local mechanics, and boy... I got lucky. I called the number on Apple Maps to see about a transmission fluid leak. James answered with a congenial and professional attitude. He came out ASAP to do an inspection and was immediately able to determine that my transmission was fine; however, I had a bad, leaking valve cover. He charged $100 for an inspection, which acted as a discount when I proceeded with the repair. Since the manifold was being removed to access the valve cover, he asked if I also wanted to get my sparkplugs/coils serviced. He didn't try to sell me on any extra services; he was genuinely interested in taking care of my car. I got my sparkplugs replaced, ignition coils replaced, and a full set of fresh valve cover gaskets with parts+labor totaling ~$900. My 2010 Nissan Xterra with 130k miles has been driving great ever since. James is an honest mechanic who has a passion for treating cars right. His prices are extremely fair, and I would recommend him to anyone in the area. read more

Quantum Mobile Mechanic - Engine bay post service - Auto Repair Near Me

Fast and very communicative. The owner is transparent and honest. Made my final decision to buy a car because of these guys. Thank you!

There are no words to describe how good of a service I recieved from Quantum. I had a check engine light on for my 2010 dodge charger and James came same day to diagnose it. He was very informative and professional about what was going on with my charger and even took the time to walk me through what the problem was. He was very honest about the repairs needed and even gave me some tips to save some money. He ended up making all the repairs same day and even gave me some advice on how to go about getting repairs done on my other vehicles I asked him about. I couldnt ask for and recommend a any better mechanic! What made this experience even better was the fact that he comes to you! No hassle driving around and leaving your car at the shop. Thank you Quantum for your excellent service. read more

I had an excellent experience with Quantum Mobile Mechanic and am so grateful I booked a pre-purchase inspection. It literally saved me thousands of dollars and a major headache. The owner, James, was very responsive from the start and took the time to explain everything clearly and thoroughly. He was patient, honest, and came across as very trustworthy - which is so important when you're dealing with used cars. The technician performed a very thorough inspection and uncovered major issues with a vehicle I was extremely close to buying without an inspection. Because of their detailed report and clear explanations, I was able to walk away from a bad purchase with confidence. If you're considering buying a used car, do not skip a PPI, and definitely call Quantum Mobile Mechanic. Worth every penny and then some! read more

Quantum Mobile Mechanic was exactly what I wanted! Someone who I could trust, who would explain everything, and go above and beyond to ensure that all my issues were resolved. You won't get better quality for the price either. 10/10 I won't be going to anyone else. Thank you Arthur! read more

I had a great service experience with Quantum Mobile Mechanic. Technician Jacob completed a transmission drain and fill and replaced the serpentine belt, and the whole process was very easy to schedule. Having a mobile tech come to my place made everything convenient and stress-free. Jacob was professional, confident, and delivered quality work. The pricing was also very reasonable especially considering the quality and service provided. I definitely plan to use their services again in the future. read more

Very convenient service, they come to your area and give an honest diagnostic without upselling. My technician, Jacob, did a great job. He was very transparent and didn't sell me anything I didn't need. He fixed whatever was wrong with my car. Thank you Jacob and Quantum Mobile! read more

Wonderful service! Fair & not trying to oversell you! Great work, value & the mechanic explained everything throughly and even showed me the difference in my car with the issue & how it should look. Use them & you won't regret it plus they come to you! These guys are the best and don't try and take advantage of a woman who knows very little about cars! read more

Excellent same day service!! Jacob changed my brakes in a hour. I was very pleased with their service. Highly recommend

Communication was great, they respond fast and answered any questions I had in a timely manner. Did a thorough inspection of a vehicle I was looking into at a dealership. Would definitely use them again if needed. read more

I can't speak highly enough about this business. I found them on Yelp and requested a quote. The owner, James reached out right away. Super professional and was very upfront with everything. He answered any questions I had and made sure I understood everything before proceeding. His technician, Jacob came out and was the nicest guy too. He explained everything to me as he was doing it and answered any questions I had. The owner, James really cares about giving good service and it shows. It's so hard to find honest mechanics these days and this guy is it! Top notch service and quality of work all around. Would highly recommended to all. read more

James was quick and responsive to my request. I called in the morning to get a same day pre purchase inspection and he was able to fit me into his schedule. He did a thorough job of inspecting the car and gave me all the information I needed right after he was done. Thanks James! read more

Quantum was very reliable, thank you James and his technician Eddie for helping me to get ready for my road trip to San Francisco tommorrow, by fixing turn signal light bulb, it was a quick fix but I am glad someone helped me to get this done. read more

I'm in the Bay Area and I needed an inspection on a vehicle in Upland. I called James and he promptly took my call and told me how he could be of assistance. He went to the dealership the same day and was able to perform a PPI on the car. I got a detailed report the same day. While speaking with James, I could tell he was very knowledgeable about cars and had a genuine enthusiasm about the work he does every day. He was very detailed about what he looks for in an inspection and he gave me some insight on the dealer themselves. I ended up purchasing the car thanks to James insights and examination. Thanks James! read more

Jesse you did an amazing job on fixing my air conditioning. Just in time for my move to Arizona. Showed up on time and kept me updated on time frame. Would highly recommend this company Very reasonable on price read more

I am very pleased with James service very knowledgeable and professional taking the time to explain everything from start to finish. The value of the service is so great, he was able troubleshoot the electrical problem my vehicle had and fixed it. He got my vehicle up and running in couple of hours very impressed with the skill. I can say he gained a lifetime customer because of my experience with the valuable service I was given today. I will highly recommend him to family and friends for any future repair opportunities. Thank you James! read more

Quantum Mobile Mechanic - So awesome!! It's mobile service to your convenience and no hassle or waiting. - Auto Repair Near Me

They did a great job resolving a suspension issue on my Tesla model 3. I was 100% happy with their response time, expertise and the quality of the work done. I won't hesitate to use them again! read more

Prompt and knowledgeable. Set us on the right track and would definitely hire again to help us out.

I ask for a quote for a specific job. I got a quick response and concise pricing for the work. A few correspondences later, I did not use this shop for this particular project; perhaps, next time. My review is based on professionalism/customer service but no work. read more

If you're looking for an honest, reliable, and fairly priced mechanic, James is your guy! I needed my rear shocks done on my Mazda CX-5 and began my search on Yelp. I sent out my "project" to other mechanics in the area and James was one of the first to reply and I love that he sent over a detailed breakdown of the estimate along with other items I needed a quote for as well. I was able to schedule that same week! Weekend availability is a plus! He had his mechanic Jacob perform the service and he did a great job! Super friendly and honest which is hard to come by with mechanics sometimes. Thank you James and Jacob! read more

Good experience. On time, friendly, thorough and professional. I recommend Quantum Mobile Mechanic. read more

Quantum Mobile Mechanic - Picture of the car. - Auto Repair Near Me

My car started leaking coolant on my way to work. I called up Quantum Mobile Mechanic and spoke with James. He made the process smooth and simple from start to finish! While it's rare to have a diagnosis and problem fixed the same day (actually within a couple of hours), James made it possible. James was very communicative throughout the process. He went above and beyond to make sure the diagnosis was correct and everything was fixed correctly the first time. He also didn't try to add any unnecessary work, which I appreciate. If you're in a bind, or don't feel like taking your car to the shop, I 10/10 recommend that you call Quantum Mobile Mechanic. read more

Excellent service, James helped me out of a pickle that I started with my Ford Focus a few months ago. I had started the repair myself and got in over my head. He was super accommodating as I had a complicated scenario, fairly priced, and most importantly he was honest, which is hard to find with a mechanic. 10/10 recommendation! read more

My vehicle broke down at a shopping center. I called James from Quantum mobile mechanic and briefed him on what happened. He immediately said not to worry he will help. He diagnosed my issue within 30 minutes. He had my vehicle fixed and back on the road within 1.5 hours. He is trustworthy and his pricing is beyond fair. If you ever need a mechanic, Mobil or for regular maintenance, James is the one to call. read more

Great service quick service! Mobile and just showed up to my house was done with my breaks in like 45 minutes.

Unfortunately James no matter what you wanna clam it was, to have it run 10 times worse with more problem then before you touching it makes zero sense. I would have rather had it the was it was then the way you "fixed " it. I do blame you i didn't touch it. If you weren't confident in your skills and all your diagnostics tools and if it was so bad why take my low budget money. You should have left it alone. Everyone want to make excuses and not responsibly. read more

Quantum Mobile Mechanic - What i was told i needed - Auto Repair Near Me

James was amazing! From start to finish, he gave me the most efficient price on a throttle body replacement and did an amazing job. So thankful for Quantum! read more

I had a couple repairs done on a 2012 Jeep and each interaction I had with either James or Eddie were cordial, timely, efficient and effective with their customer service. They both were clear on the service to be done, showed me old and new installed parts, answered my questions, along with suggestions to keep the vehicle running safely on the road. I was back in the saddle in no time. read more

Got my starter and alternator replaced by them and got my car back on the road again. Very grateful they were able to come out as fast as they did. Very honest, helpful, and convenient. My car hasn't run this well in so long, highly recommend to anyone considering choosing them for car repairs. read more

Extremely disappointed with their service. I gave a description that the window rolls down but not up and they quickly provided a quote which included the replacement of the motor. This was done without any diagnostics. Upon completing the job, the issue still existed. When asked if they can put the old motor back, the answer was that with the new motor they are able to manually roll up the window but with old one they can't. Which makes no sense because from the cameras in the garage I can clearly see that the window was rolled up manually before the replacement. Then gave some explanation about some computer part that isn't communicating correctly which could be the cause. So basically I was charged $250 for an unresolved issue. Would not recommend getting service from them. read more

The service was great! the response time was fast, I got a quote late at night to get the water pump replaced on my car and the technician Jacob came out the next day and he arrived early and did a great job. read more

Owner and employees communication skill level is low. We made agreement's to come to my work. Then he send his driver to my house. Right off the back bad vibes and lack of communication. read more

the service involved the replacement of the alternator for my 2006 Nissan, maxima. An estimate for the repair was promptly provided. Once an agreement was reached on the repair cost, an appointment was scheduled, the mechanic showed up and performed the repair in my driveway in a timely fashion. read more