'01 Celica Jerking Problems

So I bought a 2001 Celica a couple months back, and since then I've been having all sorts of problems. Initially there was a problem with the cooling pipeline so the engine was overheating, but that seems to be fixed now.

The main problem I'm getting right now is that the engine will every once in a while "hesitate" or "jerK" pretty violently while driving. At the same time that this happens the engine light will flash on temporarily and then flash off. Not knowing anything really about cars myself, I've taken the car to the dealership service center 4 times now and they haven't been able to fix the problem. Part of the issue is that they never seem to be able to reproduce the problem, so they'll give the car back and I'll be able to reproduce the problem in a few days. The problem seems to occur more when going up hills, and I'm also wondering if it might be related to the temperature. The last time it happened to me, it was jerking pretty much the entire trip and it was a hot day. Also, the engine has actually died a couple times as a result of this jerking.

Anybody have any idea what this could be? The service center (which is Mitsubishi) said I should maybe try taking it to an authorized Toyota service center.

Thanks!

Did you try hooking up an OBDII scan tool to see if you can read any diagnostic codes from it? Sounds like it is misfiring.

Yeah, the mechanics said they tried that, but that they didn't have the Toyota specific code reader, so it might be slipping under the radar. I plan to take it to an authorized Toyota service center pretty soon to see if they have any more luck.

Well the mechanics don't seem to be able to reproduce the problem. They said that it's not storing any codes in the computer, even though the engine light has flashed on, so they can't diagnose the problem.

sounds like misfireing to me to did you change plugs wires roter and roter cap recently because if you did or had it done that could be y but seems weird that only happens so often have them check that and ur timing idk its weird tho

Dude, I have a 2000 Toyota Celica GT and the same exact thing happend to me. I took it to the dealership and they said it was the catalytic converter
http://en.wikipedia.org/wiki/Catalytic_converter

well, needless to say... the dealership (at least in sc) charges a whopping $1300 for this baby to be fixed. Ouch. Luckly for you, there are other alternatives...
a. find and buy the catalytic converter for your car, universal, factory doesn't matter. Install it yourself. ( You will need a hydrollic lift, a couple of buddies who know cars, and tools. some welding may be required for universal cats) Pricing will vary.

b. go to a muffler shop. Midas, Meineke, etc... Midas was the shop that personally fixed mine. Grand total including labor was around $300. In fact, the guy at the dealership said personally this is what he would do if it were his car. I had the cat replaced with a universal one, drives like new.
no sputtering, shaking in idle, no violent jerks from one gear to another.

which ever you may choose, both will make that annoying check engine light to go away..woOt! Good luck! email me if you have any further questions..:smokin:

Not sure what the dealerships deal is. If your engine light goes off even for a second there will be a code stored in your cars ecu. They should be able to read the code and diagnose from there. Sounds to me like you either have bad or improperly gapped spark plugs, if you have an automatic it could be your torque converter, or like another guy said theres an emissions issue (but with that it should be easy for them to figure out). Most likely if thats the issue you would get an off the wall o2 sensor reading tripping codes to your ecu. Does your exhaust smell like oil or gasoline excesively?