really awful
Crashes / Fires:
4 / 0
Injuries / Deaths:
1 / 0
Average Mileage:
81,107 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2003 Toyota Tacoma engine problems

engine problem

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2003 Toyota Tacoma Owner Comments (Page 1 of 2)

problem #22

Aug 282016


  • 171,000 miles


Loss of accelerator due to bad throttle position sensor/throttle body. When you ease off the accelerator the vehicle will lose all throttle response. Then you have to "work" the accelerator in and out until it starts responding again. It happens on take off or anytime you back off on the accelerator. It has cut off on me trying to pull out into traffic and I almost got hit! it has happened on the interstate and I had to try to work my way over with no throttle and try not to get run over! it now happens every time I drive it. Toyota doesn't sell a new tps for this vehicle now ( a $40 to $50 part)Toyota will be happy to sell me a new throttle body for $1400 and that doesn't include labor. I thought manufacturers were required to provide parts for their vehicles.

- Murfreesboro, TN, USA

problem #21

Aug 152016


  • 200,000 miles
I was driving down the highway experience loss of power such as fuel push the throttle down a couple of times it pick back up happened to more times within 10 mi1nutes it did not throw a code been checking it may relate to a throttle body problem been reading about problems with the throttle body do not want this to happen in heavy traffic or pulling out in front of traffic please let me know what or how to take care of this problem

- Sunrise, FL, USA

problem #20

Jul 152016


  • 240,000 miles
Intermidiot loss of throttle responce, from standing at light or stop sign and from acceleration. Hesitation during acceleration until pedel is pressed fully and ossulation while driving at a steady speed on hwy. * warning codes present**

- Moss Point, MS, USA

problem #19

May 312016


  • 246 miles


I was driving my vehicle 2003 Toyota Tacoma on highway 156 downhill to hollister, ca I was going approx 65 mph and it just jerked back and lost power I was only able to go 40mph no higher, the engine light has not turned on and it seems I am getting no kind of diagnostic error of what could be wrong.

- Hollister, CA, USA

problem #18

Dec 022013


  • 120,000 miles
While driving down the highway, I moved into the left lane to pass another car. When I stepped on the accelerator the nose pitched forward and the engine felt like it was not getting any gas. I was able to press the accelerator nearly all the way to the floor to continue getting power to the engine, but the first 2/3 of the pedal stroke were completely unresponsive. A check engine light came on and it was diagnosed as a throttle body issue. After doing some research, this seems to be a well documented issue on a number of Tacoma forums. The cost to replace will be $1400 dollars new or $400 dollars used. I am skeptical to purchase a refurbished part due to the known issue with it. This has happened a total of 6 times in 3.5 years of owning the vehicle and seems to occur in colder weather. Typically after pulling over and shutting the car off for 30 seconds, the issue is gone. It will undoubtedly happen again, but you never know when.

- Decatur, GA, USA

problem #17

Jul 072015


  • 101,000 miles
There is a serious hazard with the throttle body where hitting the gas pedal when accelerating will sometimes cause the truck to act as though you took your foot off the pedal - turning left with oncoming traffic almost caused an accident when the truck did not accelerate as you would expect when pressing the gas pedal. I had my mechanic try to diagnose the problem before looking up the symptoms online, and he traced it to the actuator in the electronic throttle body system. Researching online after discovering this, it seems there is a major issue with the 2003/2004 trucks with this electronic throttle control system hybrid. This is extremely dangerous and I would have thought this would have been recalled based on the known issues with Toyota's throttle control systems in the past. The system does not throw a check engine light code when this happens.

- Mount Pleasant, SC, USA

problem #16

Dec 102013


  • 108,000 miles


While driving in traffic the throttle stuck at above normal idle and the check engine light came on. I was able to exit the traffic but the idle would not come back to normal curb idle. What my mechanic has told me is that the throttle body assembly has failed and they can only get the part from the dealer. If this had happened on the freeway the outcome could have not been so good. I hope Toyota is aware of this problem and going to address the situation.

- Keller, TX, USA

problem #15

Nov 032013


  • 126,000 miles
The problem that exists is on my 2003 Toyota Tacoma. It will all of a sudden lose power and have no throttle response, almost as if it was hitting an engine governor. The rpms usually drop anywhere from 200-500 and then comes back up. The power would slowly come back after keeping my foot on the throttle. It consistently does it after accelerating out of an intersection (usually around 25 mph or while cruising (around both 45 mph or 75 mph) on the highway. This drop of power or lack thereof is a huge safety issue, especially when pulling into an intersection or needing quick acceleration to avoid an accident. I have read about many others with the same issues with their late model Tacoma. The parts to fix the issue are very costly and the problem seems to be widespread. [xxx] request research. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Franklinton, NC, USA

problem #14

Jul 292013

Tacoma 6-cyl

  • 188,707 miles
Coming to a stop approx 2 mph the engine suddenly revved very loudly and the truck show forward. The brakes did not stop the truck. I swerved to avoid the campsite we were at and hit a tree very hard. The engine however continued to rev loudly and I shifted to park. With the engine still very loud and the wheels spinning I had to shut the engine by removing the key.

- East Islip, NY, USA

problem #13

May 102010

Tacoma 4WD 6-cyl

  • 45 miles
I bought this truck brand new in March 2003 and have had many problems, but nothing you don't expect with vehicles today or anything Toyota did not eventually fix, until now. About a year ago while driving down the road at about 45 the truck just lost power and stalled on me. I was almost not able to get it off the road and of course the person behind me almost rear ended me and was highly agitated I had stopped in the middle of traffic and appeared to be driving like a teenager learing to drive a manual shift transmission. When I took it to the dealer I was told it was a bad maf sensor which was replaced along with other items which cost $400. This did not fix it and after much trial and error and research I have found it was the throttle body and one of it's sensors that can't be replaced. When I mentioned this to Toyota, they disagreed and said this was impossible. It is funny how many complaints are here and how many more are having this issue who don't even know to file a complaint here. My local Toyota specialist (not the dealership), who I trust and has spent a week with my truck driving it and testing it and still only charged me $80, has also confirmed the problem, a bad sensor and the only fix is to completely replace the throttle body assembly at a cost of about $1,000 or so depending on availablity of parts. This is an obvious problem with the 2003 and 2004 models only and have heard claims from Toyota mechanics "off the record" that Toyota knows about the problem and refuses to acknowledge it. It has come to the point that I don't let anyone in my family drive this truck but me, it is too dangerous. My kids don't ride in it with me either because it could stall as I am trying to cross traffic and the results could be deadly. Please, please do something about this, I am going to have to spend the money because I can't wait to fix this, but maybe, just maybe you can save others the money and possibly their familes lives!

- Stafford, VA, USA

problem #12

Jul 312011


  • 125,000 miles


Vehicle loses power unexpectedly and is inconsistent. Has happened before to me and many, many times by others with the same vehicle. A poorly designed/engineered accelerator pedal position sensor appears to be the issue. Toyota has been notified by me multiple times but refuses to acknowledge this serious flaw in their vehicle. Most recently, I was nearly rear ended when on the freeway, the vehicle suddenly lost power. Fortunately the driver behind me was conscious and was able to make an emergency maneuver to the other lane. Someone will die from these problems! this has been well documented by many at www.ttora.com/forum/showthread.php?T=13283&highlight=apps+fix I ask that the nthsa please investigate and do something about this. It appears many of us, including myself, have submitted complaints on this issue and nothing has been done. One may argue that this is an 8 year old vehicle so no reason to investigate. This issue has been brought to your's and Toyota's attention since 2005. It needs to be investigated! please.

- Corrales, NM, USA

problem #11

Dec 202010


  • 120,000 miles
The contact owns a 2003 Toyota Tacoma. The contact stated that the hook that held the floor mat in place loosened and caused the floor mat to become stuck under the accelerator and brake pedals. The contact was unable to stop the vehicle while driving 20 mph in the rain. The contact took the vehicle to an authorized dealer who had previously replaced the hook. The dealer did not have any record of the previous repair and stated the the contact would be responsible for the costs of a replacement hook. The floor mat had not been removed. The failure mileage was approximately 120,000. Updated 03/03/11 updated 03/07/11

- Los Angeles , CA, USA

problem #10

Mar 292010

(reported on)

Tacoma 6-cyl

  • miles
2003 Toyota Tacoma consumer states unintended acceleration. The consumer stated the sudden acceleration only happened at low speeds. Updated 06/08/10.

- Tucson, AZ, USA

problem #9

Aug 012009

Tacoma 6-cyl

  • 92,000 miles
My Toyota Tacoma pre runner 2003, throttle position sensor failed on the freeway and I could not accelerate. Almost crashed because traffic was really going fast and I had no throttle response. I put the truck in neutral and I put my emergency lights on and rolled to the nearest of ramp. If it wasn't for my years of experience driving, this would not have been so easy. This is very common but the repairs are not. 1500 dollars at the dealership. There are several cases of this occurring if you go to Toyota forum you will see this is not a unique situation. This started when I first got the truck in August 2009 but who knows if the previous owner new about the problem. I think she did. I cannot fix it because they only sale the entire throttle body which cost 1200 dollars plus labor 160 dollars. Almost 1500 dollars.

- Sun Valley, CA, USA

problem #8

Sep 052007

Tacoma 6-cyl

  • Automatic transmission
  • 51,514 miles
I was the number 3 vehicle at a red light. First car went through (thinking the light had changed). Second car moved into first place. I started to follow and when I realized he had stopped I applied my brakes. I could feel the truck lurch even though I was still pressing the brakes as hard as possible. I slammed into him and caused damage to both vehicles. My foot was not on the gas pedal at all.

- San Jose, CA, USA

problem #7

Feb 052007

Tacoma 6-cyl

  • Automatic transmission
  • 45,000 miles
- the contact purchased on 07/29/03 a 2003 Toyota Tacoma four door dbl cab. The first failure occurred on 4/25/04 while slowly pulling into a parking place with and lightly accelerating, the engine revved so fast the truck drove over the parking strip and crashed into a pillar on the sidewalk, causing $5000 worth of damage to truck, and $6000 damage to the pillar. During the second occurrence on 10/09/06 vehicle stopped at a red light and the engine accelerated so the contact put it in to neutral and engine revved faster. The driver then shifted the vehicle back into drive and engine returned to normal in a couple seconds. During third occurrence on 02/05/07 while stopping at a red lightthe engine revved and went back to normal before the contact5 could turn off the key. If there had been a car in front of the contact's vehicle it would have caused a crash. The first two times the contact took the truck to the dealer. Each time they could not find anything, and gently suggested that maybe the accelerator and brakes were both engaged at the same time. First time the contact's foot was on the accelerator, and the other times it was only on the brakes, that was the first thing the contact checked. The service manager advised her not to drive this vehicle so she rented a vehicle for a couple days. They had someone from Toyota come to check it out, but they could not find anything wrong.

- San Jose, CA, USA

problem #6

Apr 252004

Tacoma 6-cyl

  • Automatic transmission
  • miles
First instance 4/25/04 slowly pulling into a parking place with a light touch on the accelerator, the engine revved so fast the truck cleared the parking strip and crashed into a pillar on the sidewalk (picture available) $5000 damage to truck & $6000 damage to the pillar. Second instance 10/09/06 stopped at a red light. Engine revved up, put it in neutral & engine revved faster. Shifted back into drive and engine returned to normal in a couple seconds. Third instance 02/05/07 just stopped at a red light. Engine revved up and went back to normal before I could turn off the key. If there had been a car in front of me I would have crashed. First two times I took the truck to the dealer. Each time they could not find anything and gently mentioned that maybe the accelerator & brake were both engaged at the same time. First time my foot was on the accelerator & the other times it was only on the brake. That was the first thing I checked. The service mgr. Advised me not to drive it so I rented a car for a couple days. They had someone from Toyota come to check it out. Could not find anything wrong. Last time was just the other day. Have not called them yet. 2003 Toyota Tacoma four door dbl cab. Purchased 07/29/03 capitol Toyota.

- San Jose, CA, USA

problem #5

Sep 042006

Tacoma 4WD 6-cyl

  • Manual transmission
  • 65 miles
After driving for approximately 2 hours, on three separate occasions, the vehicle would intermittently lose significant power. It felt as though I had taken my foot off the throttle. After my own investigation, I learned that Toyota has a history of this problem, particularly with their 2003/2004 model Tacoma's. evidently, their accelerator pedal position sensor (part of their throttle by wire design) fails. This created a few serious safety situations for me when the throttle failed to respond when needed. After reporting this to the dealer, they inspected the vehicle and did determine the apps was at fault. Numerous accounts of this happening with other owner's is readily available via the various bulletin boards on the web. Compounding the issue, is the fact that this sensor cannot be replaced without replacing the entire throttle body assembly at a cost of $1000 or so. Toyota initially responded that they've never heard of this issue yet others have reported to them prior to me which indicates either they have a very poor process for logging issues or are trying to avoid another recall.

- Corrales, NM, USA

problem #4

Mar 152005

Tacoma 4WD 6-cyl

  • Automatic transmission
  • 50,000 miles
At any time, my 2003 Toyota double cab 4X4 Tacoma pickup truck will lose all power as if I have removed my foot from the accelerator pedal when in fact I have not. This will cause my truck to drastically decrease speed until I pump the gas pedal until it decides to work again and pick up speed again. I have done much research on this issue and have found that the cause is a faulty "drive by wire" throttle body which is causing this. The throttle body on these trucks are computer controlled. You can only open the throttle body butterfly the first 25% with the pedal then the computer opens it the rest of the way. These throttle by wire throttle bodies are crapping out left and right and Toyota is trying not to replace them under the power train warranty. They are claiming it is covered under the 3/30 bumper to bumper warranty and not the 5/60 powertrain warranty. I feel that this is a safety issue and needs to be addressed as it causes me to loose control over the vehicle and it is putting myself, passengers and others on the road in danger. What if this happens if I pull out in front of a dump truck" what if it happens when I am crossing a train track?" I think it is a serious loss of control issue and it should be a recall item pure and simple.

- Richmond, TX, USA

problem #3

Apr 202005

Tacoma 6-cyl

  • Automatic transmission
  • 45,000 miles
Throttle body sensor went bad, and in turn, caused the truck to lose about 90% of its throttle. It happened to me several times in high traffic, causing me to lose almost all power, and cars behind me to slam on there brakes.

- Coral Springs, FL, USA

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