Two dashboard lights illuminated at the same time: the Check Engine light and the TRAC OFF light. At first I really didn't notice much of a difference, but after 2 days I experienced significant power loss. I would pull out into traffic, and would be okay until about 20mph, then have no power. It crawled while trying to get up to speed. I read on the internet that if you disconnect the battery and open the gas cap the lights would go out and the problem would go away. I did this and IT WORKED; or so I thought.

I then left for an hour trip (I know, dumb) and within 15 mins the lights came back on and I couldn't get the truck over 60mph on a major highway. I actually stopped at a rest stop and disconnected the battery and removed the gas cap. Again this shut off the lights but only for about 5 mins. Then the power loss was back.

Took to my local mechanic who I trust and he said it was a known problem that was something called a Technical Service Bulletin but not yet a recall. Apparently the Tundra and Sequoia are recalled for this problem but not the Tacoma. I don't get it. I was told to keep my receipts ($1,870.68) - right after Christmas, thank you - and hopefully one day get reimbursed if it becomes a recall. I can only hope this is a no interest investment into my future.

This was very inconvenient. I had to rent a car while it was being repaired. The fix is relatively easy to do with a little mechanical ability but when I factored in the wait time and cost for affordable parts from the internet I would just about break even. The most frustrating thing is that this is a known issue on Tacomas & Tundras but since it is not a safety concern there is no recall. It's just guaranteed money in the Dealers pocket.

If you have a 2012 or older Tacoma or Tundra, do yourself a favor and research the problem and know where you can get the most inexpensive parts. This cost me $1600 after negotiating the price down with the Toyota service department. I found out after the fact that there aftermarket parts available at nearly 1/3 the cost and your local mechanic or a do-it-yourselfer with very few tools can do the job. There a half a dozen videos on YouTube about the fix.

With no warning the Check Engine and Traction Control lights come on and the truck lost all ability to drive faster than about 25mph. Husband barely made it to service shop. Repair shop says this is a common situation on Tundras and now evidentially also on 2012 Toyota Tacomas. At 38,300 miles it needs a new air pump and diverter valves?! Quoted repair $2100 bucks! Sadly, this sounds exactly like what other 2012 Tacoma owners have been experiencing. Repair shop thought it should be covered under Federal Emissions Warranty but Toyota is not agreeing. Not sure car is even drivable to dealership 25 miles away even IF Toyota would warranty it.

This truck garage kept and very low mileage. We are a BIG Toyota driving family and this Tacoma mechanical/design defect is NOT up to expected Toyota Customer Experience.

2012 Tacoma. TRD Sport 4WD. Fourth Tacoma over 30+ years. Ran flawlessly till check engine light and Trac Off lights came on at morning start up recently. Goes to "limp" mode. Dangerous driving on any kind of highway. Dealer confirms it's throwing codes P2440, 2441 and 2442. Air injection system issues. Apparently common on the 2012's. Dealer recommends replacing "both banks of valves" for >$800. Confirms no extended warranty or special treatment from Toyota. Frustrating. Only 24,000 miles! Still chasing it. No resolution.

Update from Mar 11, 2017: Called Toyota customer service. After a confirmation of the problem with the local dealer, they "goodwilled" the repair. Thanks as a long-time Toyota customer. (My 4th Tacoma, among others.) Replaced valve assembly.