Lancer jerks when accelerates
#1
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Lancer jerks when accelerates
When ever I'm driving on the high way and go to accelerate more the car jerks and then accelerates . Also when I'm driving let off the gas and put my foot back on it . It's been doing that since I had it and my buddy said it's not supposed to be doing that. And when we were in the parking lot he wanted me to rev my car , and he said when I revved it a cloud of dark smoke came out .
Can anyone help ?
Can anyone help ?
#2
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Any codes? Usually black smoke means it's running rich, there might be a reflash for the pcm from the dealer(in Snakebit!'s post about his P0134 code he mentions it). Typically if it jerks when you accelerate it's a sign your tps is bad, or at least on it's way out, but with how much it costs I'd test it first. If you can get access to a scan tool hook it up(you can do it with the motor off, ignition on) and go into the datastream list(the scan tool has to have graphing ability to do this) and select the tps voltage, it should pull up the graph data. Slowly push down the gas and watch the graph on the scan tool, look for any flat spots while pressing the pedal down. If you see a flat spot,sensor's going. It's not a 100% reliable test, but you'd need to scope the voltage to get a 100% accurate test, and that stuff's pretty costly.
#4
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If it hasn't completely failed and throwing a code they wouldn't even know, you get the symptoms first, then after a while it'll throw a code for the signal being out of the specified range. Contrary to what a lot of people think, Mitsu's don't have a hot wire MAF, they have Karman-Vortex air density meters. The wire people see when they pull the sensor off is actually the resistor wire for the intake air temp sensor, which is combined with the air density meter. The reason CRC mass airflow cleaner says not to use it on Karman-Vortex type sensors is because they work with a small mirror getting hit with the airflow, then that gets interpreted by the pcm/ecu. The cleaner can erode the metallic backing of the mirror, making the sensor useless.
#5
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Oh, and another thing regarding the black smoke, with the scan tool, in the datastream list check out your STFT(short term fuel trim), if it's high negative then the pcm is subtracting fuel from the air/fuel ratio and you're definitely running rich. You should be able rent a scanner from advance auto, but I think they want to hold on to your license as collateral along with the rental fee.
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