idle @ 500
 

hi everyone i just notice tonight that my car's idle is on 500 only. everytime i press the gas pedal its like still reving for 2-3 seconds even though im not touching the gas pedal anymore. any thoughts? plus everytime i go on 40mph and up and then go on break slowly, the steering wheel is shaking alittle bit. how will i fix this? :confused:

So you let off the gas and the revs continue up for a second or two? Sounds normal to me...Engine isn't going to immediately stop revving as soon as you take your foot off the accelerator...

Steering wheel shake while braking at high speeds sounds like warped rotors to me!

:iagree:

Search for a vacuum leak. The low idle is quite possibly due to a large positive fuel trim in response to AFR's skewing lean at idle; the revving up would be from it running into unmetered air from a leak in real time, before attempting further correction.

If its a vac leak, it could be anywhere along the intake tract all the way to the primary O2 on headers, but my guess is something under the hood. Check out those little resonator boxes coming off the intake tubes, or possibly even a loose hose clamp.

If nothing obvious is found, spray carb cleaner around the intake -- when the idle revs up you've found your leak.

The vibration while braking is either unbalanced wheels or uneven rotors as somebody else suggested.

Good luck!

hey guys. thanks for your suggestion, i dont know how to fix it

Did you find evidence of a vac leak? If so, where?

I'm assuming your car's stock? You don't have date of model so hopefully it's not a 2009 with a lot of miles on it, which could lead to seals hardening and vacuum leaks. Hopefully it's something minor. Searching for the vacuum leak as suggested is the first step.

Hauling *** then stopping abruptly and holding the brake pedal down the entire time the rotors are scalding hot can cause buildup on the rotors which can cause the grabby feeling you're having on braking.

Throttle response looks normal to me. That's just how modern cars act.


You probably have some buildup/glaze on one (or more) of the rotors(s). Do a couple of 60-5mph hard brakes and it should "burn" the glaze off. If you don't notice a dramatic improvement, you may have warped rotors - but that is not very common.
As per Fountainhead, don't hold your foot on the brake after a hard and/or long stop as this can cause buildup/glazing. Try to keep rolling until the pads/rotors cool down a bit (not always possible to do safely).

If your rotors are warped you can also take them to a machine shop to have them turned on a lathe.

Is my idle normal? During morning like 6am idle runs at 1k and after i get hone from work . It shows between o-1 rpm

That sounds normal. When it's cold, it idles higher and settles down when the engine is warm. That's just how things work.

what full synth oil do you use on your Z?

Any full synthetic of the appropriate weight will do you just fine.

Becareful what you ask around here :inoutroflpuke:

Moble1 Full Synthetic is pretty popular here. I've been running Royal Purple.