Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Toyota Tacoma owners, lightly cleaned up (personal details are redacted by NHTSA).
June 1st 2021 I went to park in a parking space at a local mall. My truck instead of stopping it accelerated out of control jumped two stone curbs, drove though a fence and landed into a swamp. Call Toyota and they have opened a new case # 210602000065. Police report # 21-374-AC. This isn't the first time that this has happen with this truck. It happen in Aug 2019. I contacted Toyota case number 1908060035. They sent out EAA Engineering Analysis Ass. out who did a ACM.CDRX file a month later. Toyota came back said they couldn't find anything wrong and my case was closed. Another incident in winter of 2016 where my truck was stopped and it accelerated on its own and It drove in the 4 way intersection where it caused an accident. lots of damage to cars. Toyota was contacted and they sent me to a dealer for repairs. …
Tl* the contact owns a 2012 Toyota Tacoma. While driving approximately 55 MPH, the vehicle lost power and then immediately regained power. The check engine warning indicator illuminated. The failure recurred twice. The contact coasted the vehicle to a service station, restarted it, and was able to drive. While depressing the accelerator pedal, the vehicle would not accelerate past 25 MPH. The vehicle was taken to Toyota of poway (13631 power rd, poway, ca 92064) where it was diagnosed that the air system valve needed to be replaced. The contact was also informed that the air injection pump May eventually need to be replaced. The vehicle was repaired. The manufacturer was notified of the failure and the contact was referred to NHTSA. The approximate failure mileage was 133,472.
During normal driving, the check engine light and traction control off light came on and truck immediately went in to limp-home mode. I had it scanned for codes at the local auto parts store and it came back with p2440 and p2442 which seems like a common issue with a valve in the secondary air injection system. I quick google search showed that some 2012 Tacoma owners are getting this covered under a special warranty extension, so I puttered over to the Toyota dealership expecting to hear the same story, but they are telling me the ECM computer is bad. Which I am trying to get clarification on since I can't find any ECM failure issues for this make and model year.
Code p2440 and p2442. Air injection system valves are stuck open (related to emissions control unit) which causes the vehicle to go into 'limp' mode abrupbtly. This renders the vehicle undriveable, and can occur in the midst of driving causing serious danger to the driver and fellow drivers on the road. Toyota is unwilling to cover under any powertrain or emissions warranty. This issue is pervasive among 2012 Tacoma owners and Toyota redesigned the system as early as 2013 which implicates their knowledge of such a defect.
Tl* the contact owns a 2012 Toyota Tacoma. While attempting to switch the vehicle to four wheel drive, a loud abnormal noise was heard. The vehicle suddenly accelerated with the brake pedal depressed. The contact shifted the gear into neutral; however, the vehicle continued to accelerate. The contact was able to bring the vehicle to a stop by depressing the brake pedal with force. The manufacturer was made aware of the failure. The vehicle was not diagnosed or repaired. The failure mileage was 42,000.
Tacoma went in "limp mode" engine light and trac off light illuminated; cause the car to be extremely under power. Vehicle extremely under power causing to be dangerous in traffic. Code p2442 secondary injection system failure; common to other Toyota vehicles including tundra's. Toyota acted resumable with tundra's with extending warranty repairing but at this time refuses to repair known failures in Tacoma's.
While commuting to work the engine light and traction control light came on, causing my truck to slow down, very slow. It would not let me accelerate and disabled my progress to around 2000 rpms. This could have been a very serious or a dangerous situation especially if I was towing a load or in a major traffic situation. Codes - 2440 and 2442 were the causes of this scary account.
I took my 2012 Tacoma into service today with a trac off and check engine light on. I was told that the secondary air injection switching valve needed replaced at the tune of $1300. I see that many others have had this issue and with 37K miles, I find it unreal that this isn't covered under the powertrain warranty.
I started my Tacoma, the check engine light and trk off lights were on and after taking them to the dealer learned that the vechile was in limp mode. The truck will not easily accelerate beyond 30mph. This is caused by error code p2442 and p2440, from a known faulty part that Toyota refuses to replace.
When accelerating the truck lost all power and acceleration. Engine light is on. Engine will not increase RPM when accelerator is pressed. Truck will slowly drive but is unsafe to be on the road as it slowly accelerates up to 20-30mph max. Vehicle was merging into traffic from parking lot access.
Acceleration complaints in other Tacoma years
Frequently asked questions
How common are acceleration problems on the 2012 Toyota Tacoma?
NHTSA has 22 complaints about the speed control & acceleration of the 2012 Toyota Tacoma, 7% of the model year's 295 complaints.
Is there a recall for 2012 Toyota Tacoma acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2012 Toyota Tacoma, though it has 7 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Toyota Tacoma acceleration problems start?
Half of the complaints with a recorded mileage happened before about 73,000 miles, and 26% before 25,000 miles.
Is it dangerous?
Owners linked 2 crashes, 0 fires and 2 injuries to speed control & acceleration problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.