Two problems related to automatic transmission control module have been reported for the 2004 Toyota Camry. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Toyota Camry based on all problems reported for the 2004 Camry.
Recently I brought my 04 Camry to my dealer because of sulfur smell and rattle at light acceleration. The dealer verified the problems and replaced the converter and intake manifold according to the tsbs. They said they also had to re-program the ecm. Then after I picked up the car, I found everything is harder: the acceleration, steering, and braking. I found it is hard to maintain a speed whether on local or highway. On may 28,2005, while I drove the car on highway with 4 persons sitting in the car (including me), I found the steering was very hard and felted like it was locked, and I found it is very hard to accelerate to hwy speed and hard to maintain it. I brought the car to the dealer again on may 31. After having a technician test drove it, they told me it was similar to other Camrys (normal) and wouldn't want to solve my problem. I believe they never tried to reproduce my problem (by having more people sitting in the car). I think this problem is a safty issue so I file complaint with NHTSA. I also feel the car doesn't shift right and engine is noiser after the convert/intake change and re-programming.
Severe hesitation when depressing throttle to full-throttle. When pulling into traffic or when attempting to over take a vehicle engine appears to remain at idle when gas pedal is fully depressed to the floor. No down shifting occurs along with no engine rpm increase. After 2-4 seconds engine then responds. If throttle is gradually depressed to full-throttle there is no symptoms, engine does respond properly. I believe it may be a problem in communication between the throttle position sensor and transmission tcm.