2002 elantra 2.0L DOHC CApoor idle no power will not even hold an RPM parked. NO CODES!
Country: United StatesMake: HyundaiModel: Elantra GLSYear: 2002Engine: 2.0L DOHC
changed all plugs and plug wiring from Hyundai dealer. checked for codes there are/were NONE. Took breather off thinking air restriction, no change. there was no change after changing plugs and plug wires. old plugs were sooty. all 4 looked the same.
Name is XXXX XXX i will assist you the best i can, please Only accept if you are happy with my answer.You said no codes but is the check engine light ON when the engine is running .Where did you have it checked for codes .Greg
check engine light has never came on during any time since this started yesterday, and is not on now. I checked it myself with a scan tool. It idles very rough and sometimes dies, and when I step on the gas, if it increases RPM, it does it slowly and not evenly. finally when the RPMs increase if I keep the throttle still, it drops rapidly often and then attempts to come back up or sputters and dies.
Good information thank you .What i need you to do if you can is check the fuel pressure as i'm leaning towards fuel delivery problems .This is the first step you should do with an issue like yours .Please do this then get back to me .Kindest regards Greg
I could not find the shrader valve to check the presure. where is it located on this engine? also, remember I told you the old plugs were sooty so I was leaning away from too little gas and toward too much gas.
Do you have live date on your scan tool so you can check the fuel trim .Greg
With a running engine at idle let me know what the fuel trim read
OK, I will do it right now.
Good i will wait up to hear from you.Greg
i have my laptop at the car right now and i see nothing that says fuel trim. what else would it say
i have long term fuel trim and short term fuel but nothing for fuel pressure. I also have fuel system 1
Long Term Fuel Trim (LTFT).Short Term Fuel Trim (STFT)"Fuel Trim" is the fine tune control of fuel delivery by the ECU. To accomplish this the ECU increases ordecreases fuel delivery by increasing or decreasing the time that the injectors are open.By monitoring the primary Oxygen sensor(s) (pre catalytic convertor), engine coolant temperature,throttle position, air mass volume, engine speed(rpm) and to a lesser extent changes in altitude, humidity,ambient temperature, fuel quality, etcA vacuum leak or a bad MAF sensor and O2 sensor will cause you to run rich. disconnect the MAF sensor then start your engine and if it runs much better then the MAF is your issue .If your reading are over +20% or -20% then you have a problem ,but normally the check engine light will come on and give you a code Long Term Fuel Trim (LTFT)This is the control of Injection Pulse Time Open (ti) (also called Injection Pulse Width) over the entire rangeof engine operation. It is primarily calculated at idle or low load mid range engine operation and is averagedover time.In these idle/low load conditions the amount of fuel variation is small due to the relatively small amount of airinput. The computer monitors the O2 sensor and ADDS or SUBTRACTS approximately 0.001msec to theinjection pulse time (ti) in order to maintain a Lambda = 1. This amount of increase or decrease of theinjection pulse width is known as the Adaptation Value. This is the value output by the ECU when readingthe live data stream.For example: An LTFT of 1 is the factory spec for a new injector's injection pulse width (time open). Thiscorresponds to an LTFT Adaptation Value of 0.0.An LTFT Adaption Value of 0.100 would indicate a wider injection pulse width. This corresponds to a LTFTof 1.100.An LTFT Adaption Value of -0.020 would indicate a narrower injection pulse width. This corresponds to aLTFT of 0.980.The LTFT is also influence by the Short Term Fuel Trim (STFT).ShortShort Term Fuel Trim (STFT) MultiplicativeThis is the control of the Injection Pulse Time Open over the mid to upper range of engine operation. Whenthe engine operates at normal or higher load or at higher engine speeds, larger volumes of fuel and air areneeded. In order to maintain a Lambda = 1 in these conditions, the ECU monitors the O2 sensor andcalculated load (see figure 2) and compares the values against the optimal value for the fuel injection pulsewidth stored in the drive map. If this base fuel injection pulse width value does not yield a Lambda = 1 at theO2 sensor for the measured air mass, the computer increases or decreases the pulse width by a percentage(%) determined by the difference in Lambda from optimal. These percentages have been computed by theengineers at the factory from extensive dynamometer testing and are stored in a "weighted STFT valuearray(1)" in the drive maps. When the STFT reaches the limit of its adjustment it will cause correspondingdecrease or increase to the Long Term Fuel Trim. If the correction to the base value exceeds +25% or -25%for longer than 10 seconds a DTC is set for rich or lean stop for STFT.Hear are some conditions that will set adaptations faults and there causes.Intake air leaksIncorrect Fuel PressureInjector valve defective or cokedEngine Temperature Sensor defectiveEGR valve defectiveSecondary air leakFuel evaporation control system defective or leaking.Air Mass Meter defectiveVacuum leaksOxygen sensor aging (slow response)Clogged or damaged catalytic converterContaminated fuelFuel tank ran emptyCombustion altered by a mechanical failure (Spark plugs, compression, intake/exhaust valves, ...etc.)Please remember to only rate my answer when you are 100% satisfied. IF you feel the need to click either "Helped a little" or "I expected more", please stop and reply to me via the CONTINUE CONVERSATION button with the issue you have. I will be happy to continue further and do everything I can to provide you with the service you seek. Kind regards Greg.
I cannot find the MAF. Where is it? it is usually on the intake by the air cleaner but there is nothing there.
There is no MAF on this vehicle it uses MAP, that is what I have just been told.you've listed every component of the car, I already have that, I need to narrow it down to a working list. suggestions?? do what, in what order? I did get a code when I disconnected the oxygen sensor. Why am I not getting any codes when it will not idle correctly or have any power to move the vehicle faster than 5 MPH??
Hi .Yes that is correct mistyped here is information on the MAP.Get a Multimeter and test the sensor .MANIFOLD ABSOLUTE PRESSURE SENSOR (MAP sensor)The manifold absolute pressure (MAP) sensor is a pressure sensitive variable resistor. It measures changes in the intake manifold pressure which result from engine load and speed changes, and converts this to a voltage output. The MAP sensor is also used to measure barometric pressure at start up, and under certain conditions, allows the ECM to automatically adjust for different altitudes. The ECM supplies 5 volts to the MAP sensor and monitors the voltage on a signal line. The sensor provides a path to ground through its variable resistor. The MAP sensor input affects fuel delivery and ignition timing controls in the ECM.
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