What causes idle surges?
If an engine is not getting enough fuel (this is called “running lean”), due to fuel pressure (regulated by the fuel pump and regulator), restricted fuel injectors, a vacuum leak or really anything that throws off the fuel mixture going in to the engine, this can cause the surge.
Can a bad alternator cause high idle?
If your powertrain control computer is misreading idle speeds, this can cause a high idling malfunction. When your car’s throttle is malfunctioning, this can cause your car to stall or idle high. And a bad alternator can also cause fast idling in your engine.
Why does the idle surge when in neutral?
This went away the next day or so, but every time I’ve made that 4 hour drive, it happens for longer and longer each time. Now its really bad, and on top of the idle surging while the brake pedal is pressed, it ALSO idles really really high when in neutral and even sometimes surges but in fewer intervals when in neutral.
What happens when your idle is too high?
If your idle is too high (i’m guessing 1300 rpm+) and you step on the brakes the ECU thinks your coasting to a stop and kills your injectors to save on fuel… While in nuetral it’ll do the same thing surge, lower your idle and the surging will go away…
What does it mean when idle valve is screwed all the way?
If the idle valve is screwed all the way in check the throttle linkage. take the big hose off and make sure the throttle plate is closing completely. It could be that the cable is binding up, dash-pot is jammed, stop is out of place, etc.
What to do when idle surges like crazy?
1. Warm up the engine completely. 2. Remove the intake boot at the front of the TB (throttle body). 3. Duct tape the big hole shut on the lower right hand corner in front of the TB plate/butterfly. Please make sure you clean where your gonna tape so the tape doesn’t get sucked in. 4. Connect the boot back.