why is there that slight off idle hesitation with fuel injection?
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why is there that slight off idle hesitation with fuel injection?
i did a search, but all the topics that it brought up arent what i'm looking for.
i'm used to carbs that have a pretty much instant throttle response...
this is my first fuel injected rig, and i've noticed that there is a slight off idle hesitation when you just give the pedal a little jab. its not a performance thing and i've driven other peoples cars that behave the same way so i assume its pretty much just how fuel injection is. but all the same i dont like it, i'd love to just give the car a little blip of throttle and not have it act a second later.
just curious as to what mods can improve this little nitpicky problem or if its just something that comes with having fuel injection and no accelerator pumps.
btw, my '98 ws6 is completely stock at the moment, i would imagine making it breath easier would help as well as a more aggresive cam, but all the same if one of you really smart fellers could enlighten me i would appreciate it.
i'm used to carbs that have a pretty much instant throttle response...
this is my first fuel injected rig, and i've noticed that there is a slight off idle hesitation when you just give the pedal a little jab. its not a performance thing and i've driven other peoples cars that behave the same way so i assume its pretty much just how fuel injection is. but all the same i dont like it, i'd love to just give the car a little blip of throttle and not have it act a second later.
just curious as to what mods can improve this little nitpicky problem or if its just something that comes with having fuel injection and no accelerator pumps.
btw, my '98 ws6 is completely stock at the moment, i would imagine making it breath easier would help as well as a more aggresive cam, but all the same if one of you really smart fellers could enlighten me i would appreciate it.
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The hesitation is due to the electronics involved in decoding the signal from the throttle position sensor. When you punch the gas, the TPS has an output resistance or voltage that the PCM reads and has to decode to determine how much fuel is delivered to the injectors. Of course the amount is also determined by the A/F ratios which is read by the o2s and maf. With a carb, you have no computers trying to figure out what to do, it is almost instant. Hope this helps. - Patrick