Why Your 2017 Corvette Runs Rough and How to Fix It for $159

How to Fix Misfire

For 2017 Chevrolet Corvette owners, a misfire can be a disconcerting and performance-robbing issue. While the term "misfire" broadly describes an engine cylinder failing to fire properly, leading to symptoms like rough idle, loss of power, and check engine lights, the root cause in these high-performance vehicles can be surprisingly specific. Based on direct owner experiences, a recurring and significant factor linked to drivability complaints is related to the vehicle's supercharger system and its associated electronic control modules. One owner's experience highlights a targeted fix: "I had the update installed on my 2017 and night and day difference in tour mode." This points to software, not just hardware, as a key player in resolving rough operation that can mimic or contribute to a misfire condition.

Symptoms

Owners of this model report a range of symptoms that often lead them to suspect a misfire or serious engine trouble. The most dramatic descriptions include sensations akin to a "heart attack," likely referring to sudden, severe jerking or loss of power that feels catastrophic. Visible "smoke" from the exhaust or engine bay is another alarming sign reported, which can indicate oil intrusion or coolant issues related to forced induction systems.

Beyond the immediate mechanical fright, drivers experience persistent annoyances that degrade the driving experience. These include unexplained "headaches," which could be a literal reaction to fumes or a metaphorical expression of frustration from constant troubleshooting. Increased "road noise" and vibration often accompany an uneven running engine, making the cabin uncomfortable. Perhaps most critically, "overheating" is a symptom mentioned by owners, a serious condition that can be caused by or lead to a misfire, especially in a high-compression, supercharged engine where proper air/fuel mixture and timing are crucial for managing heat.

Most Likely Cause

The primary cause of drivability issues presenting as misfires in the 2017 Corvette, based on aggregated owner data, is outdated or faulty software in the Magnetic Ride Control (MRC) and engine control modules, particularly for supercharged models (like the Z06 and Grand Sport with available packages). While a traditional misfire might stem from spark plugs or coil packs, owners consistently identify a specific software update as the cure for their car's rough, uneven behavior. This software governs how aggressively the suspension reacts and, more importantly, can influence engine management parameters that affect smoothness under various loads. An outdated calibration can cause the engine and transmission to behave erratically, producing symptoms indistinguishable from a mechanical misfire. As one owner noted, the transformation post-update was so significant it was "like they fixed all of the roads."

How to Diagnose

Diagnosing this software-related issue requires a methodical approach before diving into expensive component swaps. First, use an OBD-II scanner to check for any stored diagnostic trouble codes (DTCs). While a true misfire will often log codes like P0300 (random misfire) or P0301-P0308 (cylinder-specific), the absence of these codes with persistent drivability issues is a strong clue pointing toward a calibration problem.

Next, perform a thorough visual inspection. Check for obvious issues like loose intake piping after the supercharger, damaged wiring harnesses near heat sources, or signs of oil leakage around the supercharger intercooler bricks. However, the most critical diagnostic step is to verify your vehicle's software calibration history. This requires a dealership-level diagnostic tool or a high-end aftermarket scanner capable of accessing GM module programming history. You need to check the calibration numbers for the Engine Control Module (ECM), Transmission Control Module (TCM), and the Magnetic Ride Control (MRC) module. Compare these numbers against the latest available Technical Service Bulletins (TSBs) from GM for your 2017 Corvette's specific model and build date.

Step-by-Step Fix

The definitive fix, as proven by multiple owners, is having the official GM software update performed. Here is the process:

1. Document Symptoms: Clearly note when the rough running occurs (e.g., cold start, in Tour mode, under light throttle). This helps the technician.
2. Contact a Dealership: Call your local Chevrolet dealership's service department. Reference customer complaints of rough ride/operation in Tour mode on 2017 Corvettes and inquire about a Magnetic Ride Control software update. Be persistent, as not all advisors may be aware.
3. Schedule the Update: Book an appointment for a diagnostic and potential reprogramming. As one owner shared: "I went in for the update, picked it up the next day and it was like they fixed all of the roads." (source)
4. Authorize Diagnostics: The dealer will first run a diagnostic to confirm your vehicle is eligible for the update and that no other hard faults are present. There is typically a fee for this.
5. Perform the Reprogramming: If eligible, the technician will use GM's Global Diagnostic System (GDS) to flash the latest software to the relevant modules. This process can take a few hours.
6. Test Drive: After the update, test drive the vehicle yourself, specifically in the mode where you previously had issues. The difference should be immediately noticeable.

Parts and Tools Needed

For this specific software-related fix, no physical parts are typically required unless the diagnostic reveals secondary damage. The core requirement is access to the correct software and hardware.

• GM Software Update: This is the "part." It is identified by a specific calibration number released via GM Technical Service Bulletin. The dealer accesses this through their subscription.
• Professional Diagnostic Tool: The GM Global Diagnostic System (GDS) is required. This is proprietary dealership equipment. High-end aftermarket tools like Snap-on Modis or Autel MaxiSys may offer some programming capabilities but cannot access official GM updates.
• Stable Power Source: A battery maintainer (like a CTEK MUS 4.3) MUST be connected to the vehicle during programming to prevent a power interruption that could brick the control modules.

Real Owner Costs

The cost for this fix is remarkably consistent among owners and is centered on labor for diagnosis and programming, not parts.

• Dealer Diagnostic & Update: The standard cost reported is the dealership's diagnostic fee. One owner stated, "The best part was that they only charged me the diagnostic fee which was $159.00 plus tax." (source) This $159 fee covered both the confirmation of the issue and the performance of the update itself.
• Software-Only Fee: Another owner referenced paying "$350 for the MRC software upgrade" (source). This higher figure may represent a scenario where the update was performed as a customer-requested enhancement rather than a diagnostic-driven repair, or it could include additional module updates.
• DIY Cost: Effectively $0 for parts, but impossible without tens of thousands of dollars in proprietary tooling and software access. This is not a DIY fix in the traditional sense.
• Cost of Ignoring: Driving with persistent rough operation can lead to accelerated wear on engine mounts, driveline components, and even cause secondary issues like fouled spark plugs from incomplete combustion. The repair cost then escalates dramatically.

Prevention

Preventing a recurrence of this issue is about proactive vehicle management. First, ensure your vehicle receives all applicable recalls and software updates throughout its life. Periodically check with a dealer or trusted specialist who has GM TSB access. Second, always use a battery maintainer if the vehicle will sit for more than two weeks. A low battery can cause modules to behave erratically and lose adaptive memory, reintroducing rough characteristics. Finally, address any other drivability symptoms immediately. A small vacuum leak or minor coil issue can strain the system, making a marginal software calibration feel much worse.

What Owners Say

Real experiences from CHEVROLET owners:

Owner Experiences

"So I set up searches on every site/app (carguru, Carfax, Autotrader...) and every one was either high mileage or missing options, wrecked... September 2019 coffee and CarMax said I might like this 2013 Challenger with 3,600 verified miles." — ExistingPoem1374 (source)

"Back in 2017 I probably would have bought a Porsche Cayman but didn't due to lack of AA. Ironically I bought a Corvette instead." — thejohncarlson (source)

"Quote: Originally Posted by frankbicknell I had the update installed on my 2017 and night and day difference in tour mode. I went in for the update, picked it up the next day and it was like they fixed all of the roads." — Gearhead Jim (source)

Pro Tips from Owners

💡 "Somebody said that you might look to get 55 to 60 grand out of your car. In my clearly amateur view with a limited knowledge of Corvettes, I'd say that you should be happy to get that much for it." — JK 23112 (source)

💡 "In my clearly amateur view with a limited knowledge of Corvettes, I'd say that you should be happy to get that much for it. Unless somebody lives in the Sun Belt, December is probably not the peak time for selling a "summer" car." — JK 23112 (source)

Real Repair Costs

"How much is it to ship to our local store? $1k non refundable!! Does it really have less than 4k miles, if so call and order it we'll get it when we're back in 2 weeks." — ExistingPoem1374 (source)

"The best part was that they only charged me the diagnostic fee which was $159.00 plus tax. I had the update installed on my 2017 and night and day difference in tour mode." — frankbicknell (source)

"My wife and I both think that it made a huge difference with the ride in "Tour" mode. The best part was that they only charged me the diagnostic fee which was $159.00 plus tax." — frankbicknell (source)

FAQ

Q: How long does it take to get the software update done? A: Most owners report a one-day service. The actual programming time is a few hours, but dealerships often need the vehicle for the full day to accommodate their schedule, run diagnostics, and perform the flash. As one owner experienced, they picked it up the next day.

Q: Can I drive my Corvette with these misfire-like symptoms? A: It depends on the severity. If the symptom is solely a harsh ride in Tour mode but the engine isn't shaking violently or overheating, short, cautious drives to the dealer may be acceptable. However, if you see smoke, experience significant power loss, or the engine is overheating, you should not drive it. These could indicate serious supercharger or engine issues that need immediate attention.

Q: Is this a common issue on the 2017 Corvette? A: Based on owner reports in forums, it is a known and documented issue specifically related to the early software calibrations for the Magnetic Ride Control and associated systems on 2017 models. GM issued updates to address it. One owner confirmed the prevalence, noting the update was offered "about 6 months after I got my car."

Q: Should I try to DIY this or go to a mechanic? A: This is a definitive case for going to a professional—specifically, a Chevrolet dealership. The software update is proprietary and requires GM's GDS tool to perform correctly. Attempting to use unofficial software or tools risks permanently damaging expensive control modules. The dealer fee ($159-$350) is a worthwhile investment for a guaranteed fix.

Q: Will this update affect my car's performance or warranty? A: The update is an official GM release designed to improve drivability and correct issues. It will not negatively impact performance; in fact, it should make the car smoother and more predictable. Having the update performed at a dealership adds a record to your vehicle's history and does not void warranty; it complies with it.

Q: My car is out of warranty. Will the dealer still perform the update? A: Yes, dealerships will perform software updates on out-of-warranty vehicles. You will simply be responsible for the labor charge (the diagnostic/programming fee), as the software update itself doesn't have a part cost. There is no warranty requirement for this type of corrective service.