Q: Accelerating doesn't produce increase in RPM

asked by on May 25, 2016

I'm having trouble with my car occasionally not accelerating. Stepping on the accelerator produced no increase of RPM or speed and my mechanic said it read 900 and stayed there. (Fortunately it showed up for him.) When this happens, maximum speed is 25mph. Yesterday, I had been parked for 3 hours and then started it, which did fine, but then pressed on the accelerator and it produced normal RPM. Is the problem an accelerator linkage?

The throttle opening is controlled by the engine computer and if the computer sees a problem in the system it will limit the throttle opening. You need to have the computer tested to see the codes that can cause this. The problem will cause the computer to go into failure management mode and limit the throttle body from going over just above idle until the problem goes away or is fixed. In your case it must be an intermittent problem and will need to be isolated and repaired.

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