This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
full bulletin at NHTSA ↗2018 Buick LaCrosse engine problems
moderate Owners of the 2018 Buick LaCrosse have filed 3 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of August 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
3
Recalls
0
Avg fix
$3,100
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal for the delay.
full bulletin at NHTSA ↗This service bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in other states.
full bulletin at NHTSA ↗This warranty administration bulletin provides policy information on vehicles outside of a California Emissions State who move to and register their vehicle in a California Emission State may be entitled to the 7 year, 70,000-mile Emission Select State Component Limited Warranty.
full bulletin at NHTSA ↗This service bulletin provides a repair procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3055 Set.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 3 most recent
Thermostat failure at 56,000 miles.
If stopped uphill and the auto stop activates, when you release the brake the car can roll back, and the way people stop on top of you these days your car can roll back into them and you have to repair their car. Plus it actually takes more gas than my v8 2016 GMC sierra that doesn't stop when traveling from my fueling location to my home, per the cars own computer system
The 3.6 liter engine in my 2018 Buick Lacrosse Avenir only has 53,939 when we experienced a thermostat failure. The engine temperature was dead cold, and the dual electric fans were running non-stop. When I scanned the trouble code, I found PO128 which points to a faulty thermostat. Because the thermostat is buried under the intake manifold, we had the local Buick dealership replace it at a…
Had engine trouble with your 2018 Buick LaCrosse?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2018 Buick LaCrosse?
It's a documented issue but not catastrophic. 3 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Mileage data is limited for this issue. Owners report failures across a wide range, suggesting cause is more about driving conditions and maintenance than mileage alone.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/Buick/LaCrosse.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.