QuestionQUESTION: Hello i have a 2004 sonata 4 cyl sometimes it does not want to go when at a stop no check engine light , checked codes on tran and engine no codes , changed the fuel pump the spark plugs and wires , still does it car has high miles would a change in trans oil and filter do any good ,
ANSWER: Changing the transmission fluid will likely make little difference, even if the problem is in the transmission. There is no serviceable filter on your transmission.
My question, however, is, how does your car not want to go? I see you've replaced plugs and wires (which could cause a misfire) and the fuel pump (which could cause low fuel pressure), but each of these would feel different from the other. What I'm looking for is a description of what occurs when you attempt to start from a stop and the car doesn't accelerate normally.
1. Does the engine rev up? Abnormally high? Normal? Not high enough?
2. Do you feel a rhythmic vibration?
3. Does the engine seem to slow the more you depress the accelerator?
If you're unable to asceratain the answers to the above question, your best bet is probably to take the car to a shop reputable and competent in driveability diagnosis. It seems fairly clear that you're having trouble determining what type of problem you have, let alone the specific cause of the problem. Once a good diagnosis has been made, you'll be in a better position to determine whether you can do the repairs yourself or you'll need to pay someone to do them for you.
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QUESTION: the engine seems to slow and you give it gas but no go , you have to take the foot out of the gas pedal and slowly give it gas in order to make it go faster about two times , engine dose not accelerate
AnswerYou might start by checking the following:
1. Air intake bellows intact (no leaks) and secure between the air flow sensor and the throttle body.
2. Air flow sensor installed with the arrow pointing the same direction as air flow.
3. Any large vacuum leak, such as a disconnected PCV or brake booster hose.
4. Throttle position sensor for correct readings.
5. Correct camshaft timing.
