2005 Toyota 4RUNNER engine problems

Filed Sep 23, 2026 · Engine · TX

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. The vehicle has not been inspected by the manufacturer, police nor insurance representative. Noticeable misfiring around the beginning of 2025 has just became more aggressive since 2026

Filed Aug 4, 2025 · Acceleration, Body · 205,000 miles · OH

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.

Filed Jun 27, 2025 · Body, Engine · TX

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". Also, the vehicle has an exhaust leak from the manifold area. It makes a loud ticking noise. This is going to cost approximately $1,500 to fix. The air conditioner is not blowing cold and either has a leak or in need of freon. This is another repair out of my pocket. This is what kind of pre-owned vehicle they sold me. This vehicle should have never been listed for sale.

Filed Sep 14, 2021 · Engine · 170,000 miles · UT

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.

Filed Aug 6, 2019 · Engine · 172,000 miles · MO

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 (314‑351‑3000, 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.

Filed Jul 11, 2019 · Body, Engine · 192,000 miles · OH

Severe corrosion of frame at the rear body mount location. The body of the vehicle is no longer secured to the frame at this location due to the severe rust. Significant rust also on the front cross frame member which has the tow mounts rendering them useless and unsafe. Cracked exhaust manifold causing excessive engine noise and exhaust fumes. This is a time consuming and costly repair.

Filed Oct 12, 2018 · Driver assistance, Engine · 136,000 miles · TN

The toyota secondary air system has failed rendering my car without traction control... And other lights. There is no preventative measures for this part and toyota used the exact same system on the tundra's and sequoia's with the same problem I'm having. This needs to be addressed as the repair for the system is roughly 4000.00 almost half the cost of my car... Please make them fix this on all cars where the same system was used.

Filed Aug 27, 2018 · Engine · 110,000 miles · MD

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.

Filed Aug 18, 2018 · Acceleration, Engine · 100,000 miles · MO

The secondary air injection pump is sending error messages and the vehicle is now in limp mode. The vehicle will not go over 30mph.

Filed Jul 19, 2018 · Engine · 182,505 miles · CA

Oil leak in #6 cylinder after 182,505 miles requiring an valve job.