Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2005 Toyota 4Runner owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2005 Toyota 4Runner. The contact stated that while driving at an undisclosed speed, the vehicle briefly hesitated and was unable to accelerate, prompting the contact to discontinue driving the vehicle. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the catalytic converter. The contact was also made aware that the mechanic discovered excessive corrosion covering the entire subframe of the vehicle. The contact was advised not to drive the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 205,000.
The contact owns a 2005 Toyota 4Runner. The contact stated while driving at an undisclosed speed, the radiator boiled over without warning. The contact stated that the failure was due to the head gasket. The contact called the local dealer however, the vehicle was not diagnosed or repaired. The manufacture was not contacted. The approximate failure mileage was 170,000.
When I first saw the pictures on the internet, I noticed that the front underside appeared to have rust issues. (Frontal shot) I contacted that sales person and he blew me off when I requested photos of the underbody. After several attempts, he finally sent a couple of pictures. The pictures obviously did not show the major rust issues as I have provided. The pictures were carefully fabricated not to show the major rust issues. It was apparent that the vehicle was taken off the internet while they hid the rusty underbody by applying some coating. A short time later, the dealership reposted the vehicle on their website. The vehicle was not properly advertised as having this major rust issue. I asked the salesman if his family was driving the vehicle, would he feel safe. He replied, "Absolutely". With this said, I decided to purchase the vehicle. Also, my signature is not on the "We owe". …
Head gasket failure. 2005 toyota 4runner generation are notorious for head gasket failure. Due to the poor manufacturing of the gasket it has been deteriorating and has allowed coolant to leak into the cylinder causing misfires and possibly more damage internally. including permanent mechanical breakdown or a completely ruined engine block. High risk of Hydrolock, Damaged Engine Bearings and Sludge, Severe Overheating, Catalytic Converter Failure. Any of these effects cause by this head gasket failure will be extremely dangerous to happen while driving. The vehicles is being taken to a independent mechanic 09/28/2026 for conformation diagnosis. And possible repairs. The check engine light showed the following code-P0300, P0302, P0304. The only symptom where misfiring and coolant levels depleting. …
Stationary on startup - my 2005 Toyota has been rendered worthless because of a factory defect in the blower fan that only runs when cold starting the engine. It triggers the "limp home" mode in the vehicle which overrides transmission shifting and makes the vehicle unsafe to drive. The error code for this problem is p0418 secondary air injection system relay. This is a well-known problem and has occurred in many, many of the Toyota 4.7 l engines in different vehicles. Toyota is aware of this defect in this/these part(s). This could not be predicted or prevented by servicing the vehicle at regular intervals, or any other method of typical consumer maintenance. The price for repair is in the $3-thousand dollar range. This was not a consumer neglect item. Toyota has a part in their engine that is defective, and they know that. …
2005 Toyota 4runner 4.7l v8. "check engine" and vsc trac. Codes 1441, 1444 and 2440.Toyota knows they put a faulty secondary air injection system in the v8 engines for a number of years, and now they want $2200 to fix the problem. If the faulty valve sticks open, the vehicle will automatically go into "limp mode" with a maximum speed well below safe travel speeds on highways and interstates, creating a safety hazard for occupants and others on the road. Toyota did a recall on other models with the same engine, but nothing for the 4runner. This is a know issue with the v8 engine, and they are covering the repair for sequoias and tundras with the same engine.
Tl* the contact owns a 2005 Toyota 4runner. While driving 70 MPH, the vehicle lost power. In addition, the accelerator pedal was depressed, but the vehicle failed to accelerate. The check engine and vsc warning lights illuminated. The vehicle was taken to an auto store where a technician pulled up diagnostic trouble codes. The contact spoke with a local dealer who stated that, based on the codes provided, the vehicle would be repaired under NHTSA campaign number: 05V123000 (engine and engine cooling). The VIN was not included. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 103,000.
For 3 days the car would start with engine roughness, lasting 15 seconds or so (sometimes with a cloud of smoke from the exhaust). On the 3rd day the check engine light, vsc, and trac lights illuminated. An analysis at an independent repair shop found a computer code of p0306 (engine mis-fire on cylinder 6). A borescope video of the cylinder shows small amounts of coolant entering the cylinder, indicating a head gasket leak. Searching this vehicle online and in this database shows a high number of reports of head gaskets leaking into cylinder 6. I am looking at quotes between $2500-5000 for repairs.
I'm a retired master mechanic turned aerospace engineer. On aug 24, while my foot was on the brake, the engine revved to full throttle, squealing the rear tires. This event was clearly caused by a faulty electronic throttle control circuit. I shut off the truck. When I started it again, the situation was still there. I shut it off and waited 10 seconds, then started it and it idled normally. I concluded that there was a software glitch. This happened once before about two years ago. In both cases, my truck was luckily stopped in a parking lot with the transmission in drive.
Tl* the contact owns a 2005 Toyota 4runner. While driving at any speed, the check engine indicator illuminated and remained lit. The vehicle was taken to ackerman Toyota [phone], located at 2020 hampton ave, saint louis, mo 63139) where it was diagnosed that the air switching valves needed to be replaced. The vehicle was taken to an independent mechanic where the exhaust manifold and the air switching valves were replaced. The manufacturer was not made aware of the failure. The failure mileage was approximately 172,000.
Engine complaints in other 4Runner years
Frequently asked questions
How common are engine problems on the 2005 Toyota 4Runner?
NHTSA has 31 complaints about the engine & cooling of the 2005 Toyota 4Runner, 7% of the model year's 425 complaints. The component named most often is exhaust system › emission control › catalytic convertor (4 mentions).
Is there a recall for 2005 Toyota 4Runner engine problems?
No. NHTSA lists no engine & cooling recall for the 2005 Toyota 4Runner, though it has 5 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 2005 Toyota 4Runner engine problems start?
Half of the complaints with a recorded mileage happened before about 109,000 miles, and 16% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to engine & cooling 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.