P1098 on 2021-2022 Chevrolet Silverado 1500 (LT, RST, LTZ, High Country) — Engine Coolant Control Valve Position Sensor Minimum Stop Performance
1 vehicles · 1 makes
How to diagnose and fix P1098: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Chevrolet Silverado 1500 · 2021–2022
Silverado 1500 trucks with the 3.0L LM2 Duramax inline-6 turbodiesel are prone to failure of the electronically actuated engine coolant control valve. Failure illuminates the check-engine light, can leave cooling fans running after the key is off (draining the battery), and in some cases causes the engine to run hotter than normal. A frequent root cause is corrosion/terminal damage in the coolant flow control valve actuator harness connector. GM announced Special Coverage N252508341 (September 2025) extending warranty to 15 years / 150,000 miles from in-service date for the affected valve on 2021-2022 Silverado 1500 (and 2021-2023 Tahoe/Suburban and GMC/Cadillac siblings). Owners have reported multi-month back-orders on the replacement valve (part 40009644).
Common Symptoms
- Check engine light
- Cooling fans run after engine is shut off
- Engine running hotter than normal
- Battery drain
How to Fix
Scan for codes (P1098 / P26BB are commonly reported); confirm the coolant control valve or its harness connector is at fault. Under Special Coverage N252508341 the dealer replaces the coolant control valve (part 40009644) at no charge within 15 years/150k miles. Inspect/repair the actuator harness connector for terminal corrosion. Reimbursement is available for owners who previously paid for the repair.
Sources for this issue (1)
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P1098 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P1098 mean?
P1098 stands for "Engine Coolant Control Valve Position Sensor Minimum Stop Performance." A manufacturer-specific code used by GM (Chevrolet, GMC, Cadillac, Buick) on vehicles with an electronic engine coolant flow control valve, and most prevalent on the 3.0L Duramax diesel (LM2/LZ0). The engine control module sets it when the valve's internal position sensor cannot confirm the expected minimum-stop position or reports a value inconsistent with what was commanded. Reported symptoms include a check engine light and cooling fans running at high speed as a failsafe. GM PI PIP5675G addresses P1098 and/or P26BB and identifies a software anomaly as the cause on affected vehicles, so a calibration update should be checked before replacing the valve.
What are the most common causes of P1098?
The most common causes of P1098 are: Outdated ECM software calibration (check for the GM update per PIP5675G first), Failed engine coolant flow control valve assembly, Damaged or corroded valve connector and wiring, Low coolant level or air in the cooling system, Faulty engine control module (rare). The specific cause varies by vehicle.
How much does it cost to fix P1098?
Repair costs vary widely depending on the root cause and vehicle.
Which vehicles are affected by P1098?
Au7o has documented P1098 across 1 vehicle models from 1 manufacturers: Chevrolet.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.