The supplied GM bulletin covers specified 2014–2015 Chevrolet Corvette vehicles and states that DTCs P0300–P0308 may occur when a spark-plug wire is loose at the ignition coil. Its documented inspection checks the wire connection and retaining clip before replacing the wire. This bulletin does not establish a general diagnostic order for all Corvette years or engines. Confirm the exact vehicle application and use the manufacturer’s procedure.
What should you confirm before buying a part?
The supplied catalog records are conditional. Champion CCH9300 is listed for 2015–2018 Corvettes with the Super-Chrg restriction and for a 2019 Corvette with the LT4 engine identifier. Denso ITL16 is listed for 2014–2017 Corvettes without a catalog restriction. Neither listing proves fitment for every Corvette configuration.
The catalog lists eight plugs per vehicle for these applications. Confirm the year, engine and relevant equipment before ordering. A matching model name alone is not sufficient to establish interchangeability.
The Champion records specify a 0.034-inch gap and plug type RES12WYPB4. The Denso records specify a 0.044 gap. These are supplied catalog details, not evidence that a misfire results from an incorrect gap.
If the vehicle has a replacement engine, modified equipment or unclear history, verify the application against the exact manufacturer information and the vehicle details before selecting a part.
Use the exact year, make, model, engine and relevant equipment details. A shared Corvette model name does not make every listed part interchangeable.
Which symptoms need further diagnosis?
The supplied evidence does not verify a general symptom list or establish what every warning-lamp condition means. If the vehicle is operating abnormally or a warning lamp is present, follow the manufacturer’s guidance and arrange qualified diagnosis rather than continuing to guess at parts.
The supplied bulletin states only that P0300–P0308 may occur when a spark-plug wire is loose at the ignition coil on covered vehicles. It does not support broader definitions for each code or identify a failed part from a code alone.
For the specified 2014–2015 Corvette applications, the GM bulletin identifies a loose spark-plug wire at the ignition coil as a possible cause of P0300–P0308. Its documented inspection checks the wire connection and retaining clip before replacing the wire.
The supplied sources do not provide a Corvette-wide procedure for distinguishing ignition, fuel, compression or valvetrain faults. If the connection inspection does not resolve the concern, use the exact manufacturer diagnostic procedure or a qualified technician rather than assuming an internal engine fault.
The listed products are catalog options, not a diagnosis or a guarantee that replacement will resolve a misfire.
What does this system do?
A spark plug may be the correct part only when the exact application and manufacturer procedure support its use. The supplied evidence does not establish a general plug-failure mechanism or show that replacing a plug will correct every misfire. A loose wire connection is the specific possible cause identified by the supplied GM bulletin for its covered vehicles.
What can you check safely first?
With the vehicle prepared according to the manufacturer’s safety instructions, do not disturb energized ignition equipment. For the covered bulletin applications, the documented inspection checks the spark-plug wire connection and retaining clip before replacing the wire. Use qualified service if the required procedure, access or safety precautions are unclear.
Which part numbers are worth checking?
Match one appropriate option to the diagnosed fault and exact vehicle. These may be alternatives for different years or equipment; they are not a list of parts to replace together.
What else should be inspected?
The supported starting point is limited: verify the vehicle scope, identify applicable codes, and inspect the wire connection and retaining clip described in the GM bulletin when the vehicle and engine are covered. Do not infer a valvetrain failure or authorize parts replacement from the code alone. For any further testing, follow the exact manufacturer procedure.
Installation and service precautions
Use the exact vehicle and product instructions for selection, inspection and installation. Confirm fitment before opening the package. Keep the engine off and follow the manufacturer’s safety procedure when working around ignition components. Use a qualified technician for restricted access, modified equipment, uncertain procedures or internal-engine diagnosis.
Use the manufacturer procedure for the exact year, engine and equipment. Do not substitute an unsupported general repair procedure.
Use a qualified automotive technician when the required diagnosis or repair exceeds safe owner-level inspection. Do not work on energized equipment or bypass safety devices.
Which vehicle applications are verified?
The catalog records below belong to each individual part number. Notes, engine, trim and equipment restrictions apply only to the associated entry. Confirm the VIN privately with XPart Supply where the application is uncertain.
CCH9300 — Chevrolet Corvette catalog applications
2015, 2016, 2017, 2018 Chevrolet Corvette — Aspiration: Super-Chrg
Catalog note: Gap 0.034 (in), Plug Type Number RES12WYPB4
2015, 2016, 2017, 2018 Chevrolet Corvette — Aspiration: Super-Chrg
Catalog note: Gap 0.034 in , Plug Type Number RES12WYPB4
2019 Chevrolet Corvette — Engine ID: LT4
Catalog note: Gap 0.034 (in), Plug Type Number RES12WYPB4
2019 Chevrolet Corvette — Engine ID: LT4
Catalog note: Gap 0.034 in , Plug Type Number RES12WYPB4
ITL16 — Chevrolet Corvette catalog applications
2014, 2015, 2016, 2017 Chevrolet Corvette
Catalog note: Gap 0.044, Iridium Power - Performance Upgrade with World's Smallest Center Electrode (0.4 mm Dia.) & Tapered Tip Patented U-Groove Design & Patented Ir Alloy (90% Ir)
A listing here does not override the current product-page fitment or a manufacturer supersession.
Ask XPart Supply to confirm fitmentPro Tip
Treat a Corvette misfire as an application and diagnosis question, not a reason to replace parts at random. For specified 2014–2015 vehicles, the supplied GM bulletin supports checking the spark-plug wire connection and retaining clip. Confirm the exact engine and product application before choosing a plug.
Frequently Asked Questions
Can a spark plug be selected for any Corvette misfire?
No. The supplied catalog records provide conditional applications only. A misfire does not by itself establish that a spark plug is the required repair.
Can a loose spark-plug wire cause P0300 through P0308?
The supplied GM bulletin says it may on specified 2014–2015 Chevrolet Corvette vehicles when the wire is loose at the ignition coil. The documented inspection checks the connection and retaining clip before replacing the wire.
Does a misfire code prove a valvetrain fault?
No. The supplied sources do not support that conclusion. Use the exact manufacturer diagnostic procedure or qualified professional diagnosis for any suspected internal-engine problem.
Do these spark plugs fit every Chevrolet Corvette?
No. Champion CCH9300 is listed for specified 2015–2018 Super-Chrg applications and a 2019 LT4 application. Denso ITL16 is listed for 2014–2017 applications. Confirm the exact vehicle details before purchase or installation.
Related parts and vehicle guide
Technical references
Manufacturer and technical reference material informed this guide. Public discussion activity is used only to identify questions; individual reports are not proof of the cause on your vehicle.
GM Preliminary Information PIP5159A: Engine Misfire May Be Due to Loose Spark Plug Wires
Read the technical source