Buick · Transmission · Critical code

P0746 on Buick: How to Diagnose & Fix

Pressure Control Solenoid Performance/Stuck Off

1 Buick model · 1 documented issue · 1 critical · $150-$5,500 repair

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P0746 on Buick by model: symptoms, diagnosis and fix

The Aisin AF40 6-speed automatic in 2011-2017 Regal (and 2010-2017 LaCrosse 4-cyl, 2008-2017 Opel Insignia A) develops harsh 1-2 and 2-3 shifts, torque-converter shudder at light throttle, and delayed engagement, usually 80,000-150,000 miles. GM's "lifetime fill" claim is widely disputed by independent shops.

Common Symptoms

  • harsh shifts
  • torque converter shudder
  • delayed engagement
  • flare on upshift

How to Fix

Drain-and-fill ATF every 50,000 miles using AC Delco / Aisin AFW+ (or JWS3309 equivalent) — about $150-$250 DIY (5-6 qt drained per service). Severe shudder may need torque converter or valve body work ($1,500-$3,500). If neglected past 120k miles, full rebuild may be required ($3,500-$5,500).

Typical repair cost:$150 - $5,500
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P0746 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 P0746 mean on a Buick?

P0746 stands for "Pressure Control Solenoid Performance/Stuck Off." P0746 means the transmission's pressure control solenoid 'A' is performing poorly or appears stuck in the off (low pressure) position. This solenoid regulates hydraulic line pressure that applies clutches and bands to make smooth, firm shifts; the TCM detects when commanded pressure changes aren't producing the expected response. A stuck-off condition typically means line pressure stays low. You may experience slipping, soft or delayed shifts, harsh engagement, overheating, or the transmission entering limp mode. On Buick it is documented across 1 model: Regal.

What are the most common causes of P0746?

The most common causes of P0746 are: Low, dirty, or degraded transmission fluid, Faulty pressure control / EPC solenoid, Clogged valve body passages or stuck valve, Wiring or connector fault at the solenoid, Internal transmission wear (worn clutches, leaking seals), Dirty or clogged transmission filter, Faulty transmission control module (less common). The specific cause varies by vehicle.

How much does it cost to fix P0746 on a Buick?

Published repair estimates on Buick range from $150 to $5,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.

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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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