Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

Please take a moment & say thank you by donating $5 or whatever you can to the Center for Auto Safety. Notes: Although it has a stellar record in terms of vehicle problems, initially the 4th generation (2003 - 2009) 4Runner didn't earn our top "Seal of Awesome" rating because it received poor crash test ratings for rear impacts. However it's proven to have one of the lowest driver death rates out of all vehicles (not just SUVs), so we've bumped it back up to our top award.


definitely annoying
Typical Repair Cost:
No data
Average Mileage:
177,000 miles
Total Complaints:
1 complaints

Most Common Solutions:

  1. not sure (1 reports)
2003 Toyota 4Runner engine problems

engine problem

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2003 Toyota 4Runner Owner Comments

problem #1

Feb 012016

4Runner Limited V6

  • Automatic transmission
  • 177,000 miles


Check Engine Light and VSC Trac VSC Off lights are on and will not go out.

-Replaced spark plugs with Platinum 100k mile plugs from RockAuto for about 6.00 each -Replaced ignitor coil with OEM part from RockAuto for about 55.00 -Check engine light still on, and I think it triggers the VSC lights, as well as using a non toyota OBD code reader.

-I suspect dirty or failed fuel injector possibly. -I had several error codes, including P0301 (which is cylinder 1 misfire) and P0300 which is random cylinder misfire. Also had a P0171 error which said something about system "too lean". After changing spark plugs, breaking and repairing one ignitor wire (for cylinder 4), and running with a new ignitor, I still can't get the lights to go out. I read on RockAuto, under a rebuilt fuel injector description, that someone had the o-rings go bad on fuel injector number 1 for cylinder 1, which caused a poor seal (thus too lean)...and they replaced the fuel injector which fixed the problem. Only issue for me is the OEM part is about 150 per injector...rebuilt is about 20.00. So may just replace all since car is older (now 13 years) and I want to drive it to 300k miles.

Additionally, the VSC lights seem to trigger if you use a non toyota code reader. I've been able to clear the Check engine light but it comes back. I'm also worried that when I accelerate quickly, the check engine light flashes, which I think means the catalytic converter or O2 sensors are protesting the unburned gas or fumes going into the converter.

Anyway, I've had to learn a ton about this stuff because I'm military stationed overseas, in the middle east, with not lots of local parts or expertise. I'm still researching this issue, but I love this car and was glad to find this website and discover the green seal of awesome.

- , Norfolk, VA, USA

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