I have a 2003 protege automatic with 8,000 miles on it. If I don't have time to let it fully warm up when the weather is cold, the car will occasionally hesitate at slow speeds, but smooths out eventually and runs fine when fully warmed up. On one occasion, the car was acting funny on the highway. There seemed to be a "dead spot" in the gas pedal. When I took my foot off the gas, the car would slow down almost like the brakes were applied. When I would put my foot back on the gas and passed the "dead spot" the car would jump and not accelerate smoothly. Any ideas what the problem is? I really like my new car, and would like to have this problem(s) solved. I know if I take it to the shop, they will probably come back at me with "we can't get the car to do what you are describing and can't do anything if we don't know what is wrong." HELP!!!!

Not running smoothly until warmed up is common to many makes and models and doesn't necessarily indicate a problem. Much depends on the temperatures involved and what you consider to be "warmed up." When not a legitimate fault, it can be likened to a person waking up and yawning and stretching and needing a cup of coffee to get going. I have no idea what could be causing the other problem you describe, but make a detailed and accurate list of the symptoms to give to the shop. The more information they have, the better it assists them in making a diagnosis

Thanks for the info and the quick response. I understand that some cars need to have time to warm up, but I haven't had a hesitating problem with any of my past cars manufactured in the past 15 years. I remember having this issue when cars were carbuerated. I was under the impression that fuel injection is supposed to keep a car running smoothly at all times. ON these cold mornings, I can drive out of my driveway and the car is fine. Once I get down the street and I am in stop and go traffic, I can feel the car hesitating and see the tachometer jumping like the car wants to stall. (this is accpetable for a brand new car to be doing this?) Any other ideas or suggestions?

There's definitely something wrong, but all these late model cars have such sophisticated engine management systems that you have to have pretty good diagnostic skills and the necessary equipment to do the testing, or the problem is one so common that everybody already knows the fix. I won't even hazard a guess as to what could be wrong, but I sure hope they can duplicate it when you take it in to the shop. In the meantime, you might go to Alldata to see if there's a TSB on it.

Hey! to you use write casolin in your car !
Problem is I think the throtle sensor whits is turning your car idle on and of I had a same problem whit my 95 mazda protege You can fix the problem and no cost to you:)Just find the throtlle sensor and move the sensor inn and out ,it moves abouth 1mm in and out! So good luck!

Hey! to you use write casolin in your car !
Problem is I think the throtle sensor whits is turning your car idle on and of I had a same problem whit my 95 mazda protege You can fix the problem and no cost to you:)Just find the throtlle sensor and move the sensor inn and out ,it moves abouth 1mm in and out! So good luck!

Using water remover (gas dryer) in your gas tank might help. If water precipitates out of your fuel,it will cause all kinds of performance problems in cold weather. A bottle of this stuff sells for about $ 2.50.

check the 3 inch diameter air hose from the air filter to fuel injector. flex area gets cracks and makes enging run bad with leaking air. seal with glue and duct tape or replace the rubber air hose