why does my car idle high?

Question

i recently swapped in a new motor in my 04 scion xa now when i start the car its fine but when it warms up my idle goes up to 1700 to 2000 rpms what could be the problem?

Answer 1

Timing is off, take it to a mechanic.

Answer 2

My first guess would be to check the temperature sensors. Frequently, there are a few around the thermostat. If it's possible to get them switched, that's what could have happened. Last resort, find a code reader. That should tell you, because it sounds like the computer is getting a wrong signal somehere.

Answer 3

once you put in any severe bypass exhaust factors you do away with the backpressure that your EGR valve (emmission componet) or Exhaust gasoline recirculation valve desires to appropriate perform, you fairly strengthen the quantity of unpolluted air and that ought to reason a mushy strengthen in idle as properly as occasional knocking (pre-ignition). Your EGR fairly feeds exhaust gasoline into your engine's manifold to decrease emmisions by making use of sabotaging your gasoline/air blend. next element, your intake mods might have led to the two a vacuum leak in the setting up of any new air clear out (unintentional) or it ought to no longer be connected good. you will have a foul examine valve on your brake booster, or your brake booster may be defective. the two could reason a vacuum leak and a vacuum leak of great proportions could reason a severe idle or maybe knocking under a load. So definite, any transformations on your vehicle might reason any form of issues. i'm guessing which you have the ok & N clear out good? you already know you nonetheless might desire to be sure to scrub and re-oil them with the kits they sell i wish. My CRX have been given sloppy and whilst i grew to become into checking it out I observed that airborne dirt and mud and sand were bypassing my clear out element all mutually. in all probability did no longer help that i grew to become into in Baja yet you already know what I advise. Now, one greater element. you could many times come across a school which will restoration your vehicle's subject freed from cost or much greater efficient you could circulate there and artwork on your own. I did it whilst i grew to become into in San Diego and that's the place I found out all those issues, regrettably i'm able to easily understand lots over the pc, there are various different reasons which comprise actual injury on your throttle physique that ought to try this. Your choke must be sticking? no.. (given which you had an previous carbureated style) yet you have a ninety six Honda Civic = no carb... gasoline injected rather. the desirable attempt is to close off your vehicle and borrow a smoke device and watch for the leak. i visit declare that your subject has a ninety% possibility of being an intake/vacuum leak, perchance a hose is off someplace. sturdy success and in case you like greater i'm going to do my desirable.. Anton

Answer 4

Some cars, when cold it idles at a higher rpm till they warm up, but those cars had carburetors, with fuel injection, they don´t , you needs a professional tun up, you have a problem, yours work in reverse....

Answer 5

Computer needs to be recycled. Turn off motor. Disconnect battery negative post. Then disconnect positive post. Let set fo 20 minutes. Connect positive post. Connect negative post.

Answer 6

The carburator is shot. Try putting some WD40 on the outside and see if it doesn't unstick something, like the throttle.

Answer 7

Not sure it is the timing but there an idle adjustment and perhaps it needs adjusting.

Answer 8

if the rpm's are high, the car is either cold, or needs a tune up.

Answer 9

Perhaps the timing is off?