Why do RPMs jump while holding a steady accelerator?
When holding steady pressure on the accelerator, engine RPMs can jump repeatedly while the car's power goes in and out. This surging occurs during acceleration even after completing gearbox adaptations and fluid top-offs, and it may be accompanied by crankshaft position signal failure codes.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1doing gearbox adaptation
- 2topping up gearbox oil
- 3Check transmission fluid level
- 4Inspect the air and fuel mixture
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“This is volvo s60 2014 2.5 petrol with tf80 sc gearbox. On autopilot it drives smoothly, this happens only when accelerating. Thanksss. Adaptation has been done successfully, didnt change the problem. Gearbox oil topped up properly. Only fault codes that I can see are with crankshaft position signal failures, no idea if that could even be related”source ↗
“When driving and steady pressure on the accelerator the rpm’s will start jumping around repeatedly and you can feel the power kinda go in and out.”source ↗
Where this came up
People with this problem also raised
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- 5Why is my car revving so high on a cold start?
- 3Car shakes at high speeds even with good tires and alignment
- 13Why does my car lose power when I step on the gas?