Your check engine light means the computer saw something out of range. We read the codes, then test the live data behind them so you get a named cause, not a guess.
Winter Haven
At our Winter Haven shop, the technician started with initial testing on the check engine light and the slow start after fueling.
Read the full jobHaines City
The technician retested and verified the repair, and performed a final road test where applicable.
Read the full jobWinter Haven
The technician started with an initial assessment and ran smoke machine emissions testing to test the emissions components.
Read the full jobSebring
The technician started with an initial assessment at no charge and updated the service manager within 30 minutes.
Read the full jobLake Wales
The technician found valve cover gasket(s) with covers leaking, with the severity of the leaks calling for that repair to be the starting point, and the…
Read the full jobWinter Haven
The technician started with an initial assessment at no charge and updated the service manager within 30 minutes, noting that further testing might be needed…
Read the full jobA code is a starting point, not an answer. When that light comes on, the computer has seen a reading outside the range it expects and stored a code for it. The code names the system involved. It doesn't name the broken part. One code can have five believable causes sitting behind it, and the only honest way to tell them apart is to test.
Steady or flashing matters. A steady light means the computer wants someone to look at it, and you can usually finish your errands and get it scheduled. A flashing light means the engine is misfiring right now and unburned fuel is heading into the exhaust. If it is flashing, pull over when it is safe and have the car towed or looked at before you drive it further.
Diagnosis starts with every stored code plus the freeze frame data that came with it, so we can see what the engine was doing at the moment the light triggered. Then we watch live data with the engine running. Fuel trims show whether the computer is adding or pulling fuel to cover for something. Sensor readings get compared against what the engine is actually doing. From there our ASE certified techs test the specific suspects, which is how a failing sensor gets separated from a vacuum leak or a wiring problem instead of replacing parts in order until the light goes out.
Some codes have nothing to do with how the car drives. Evaporative emissions codes are the usual example: the car feels perfectly normal while fuel vapor quietly leaks away. Sometimes it really is a loose or worn gas cap, and we'll tell you that. Often the cap is fine and a smoke test finds the leak somewhere else in the fuel vapor system.
You leave knowing the actual cause, with inspection photos on your phone and a written quote. Whether you fix it that day is a separate decision.
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Our experts diagnose and resolve any issue.
This one is worth checking the cap on before anything else, because sometimes it really is a loose or cracked gas cap. When the cap seals fine, the same code usually means a leak somewhere else in the fuel vapor system, and a smoke test shows us where.
A flashing light means a cylinder is misfiring while you drive. Ignition parts, fuel delivery, or a mechanical problem in that cylinder are the usual causes. We identify which cylinder and why before anything gets replaced.
The fault happened, cleared, and the code is still stored in history with the freeze frame data attached. That data tells us the speed, load, and temperature when it triggered, which is often enough to reproduce it on purpose and catch it in the act.
Usually an emissions or sensor code that never touches drivability. It still matters, because it can hide a second problem behind it, quietly cost you fuel economy, and it's the first question a buyer's mechanic asks when you go to sell or trade the car.
Common and frustrating. A code points at a circuit or a reading, not always at the component in its name, so an oxygen sensor code can be a leak upstream. Live data testing sorts the failing part from the part that's only reporting the problem.
Clinton and Ramon helped me with my Chevy suburban after my check engine light came on. They took me right in solve my problem and it was something simple so they didn’t even charge me. I’m thankful for a shop like this in Wauchula.
Gus Masterson
Verified Google Review
Ms. Cece, Mr. Art, Mr. Jeffrey and the entire Johnny's Automotive family are wonderful people, experienced and exhibit the utmost pride in their work and professionalism. I took my wife's 2017 Lincoln MKC to the one place that I knew would take care of my wife's car. It's her main drive and she's going back and forth from Winter Haven to Tampa almost daily. Johnny's Automotive and team probably saved me thousands of dollar in an unnecessary (for now) turbo repair for what turned out to be a vacuum leak affecting my wife's cars power and check engine status. Full break service has left her car braking smooth. She's now happy and most importantly, reassured, that she'll be safe in her car. You can't put a $$$ on that kind of peace of mind, for both my wife and myself. Thanks Cece, Art, Jeff and team! We'll be back next lil change to do tune-up and leave my wife's car like it was when it rolled off the lot new!
Mr Morales
Verified Google Review
Great people, fair price, and fantastic service! whether you just need a oil change, or need that check engine light to go away Johnny’s got your back.
Lincoln Mattingly
Verified Google Review
New to the area, so after reading Google reviews, i went to Johnny's with some dashboard lights on. They were very courteous and friendly and once they ran the diagnostic tests explained the issues that were found. The waiting room is comfortable, clean and well stocked. They sent me home and when my car was ready the next day they had me picked up. My car is running like new. Will not hesitate returning for any other issues that may pop up and I highly recommend their service. Update. Back for regular service and maintenance, including new tires. Still very impressed with this business and everyone I have encountered there. Will continue to go there for anything and everything associated with my vehicle, as they have my full trust.
Ann Formentin
Verified Google Review
They will fix it right! Had a check engine light for my transmission and they fixed it and it has never came back since. Good reliable service. They also treat your car as one of their own with the utmost care and respect ^-^
TheMonteCarlo Maniac
Verified Google Review
I was dealing with a big problem on my 2007 Chevy Suburban with 431,820 miles. It was idling rough with a misfire (lean code on bank 2), and Johnny’s took the time to find out the source of a three month ordeal. You guys totally ROCK! My car is running better then ever, and no check engine light. The team at Johnny’s is very friendly, responsive, upfront, thorough, and honest. Genuinely excited to bring my car back to them next time it hiccups. From start to finish 100% satisfied.
d'Aquin Reese
Verified Google Review
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Common questions about our check engine light services.
If the light is steady and the car drives normally, yes, get it scheduled rather than parking it. If it's flashing, if the car is running rough, or if a temperature or oil light is on with it, that's the moment to stop driving it. When you're unsure, call the shop and describe what it's doing.
A scan reads the stored number, which is a useful first clue and takes a minute. A diagnosis figures out which of the possible causes behind that number is the real one, using live data, testing, and sometimes a road test. That gap is exactly why people replace parts that weren't broken.
Usually yes, after the car completes its own self checks over a few drive cycles. We clear the codes when the repair is done so it starts fresh, then verify the fault doesn't return. If it comes back, that tells us something too.
It will turn the light off and it also erases the freeze frame data we use to find the cause, so it makes diagnosis harder. The light also comes back once the fault repeats.
We can tell you what system that code covers and what it usually turns out to be, and we're happy to do that. We won't quote a repair on it, because the same code lands on different parts in different cars. The quote comes after we've tested and know which one you have.
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