306 accelerator problems

Hi everyone, I'm having a problem with my 306 HDI diesel. It revs up to 1250 RPM on its own and then decelerates intermittently. Sometimes I have to stop and restart the car for the acceleration to stop. They replaced the accelerator pedal, but it's still malfunctioning. Peugeot tells me I need to replace the computer (I don't trust them; it suggests they don't know much). An auto electrician already had this problem with a Partner, and all he did was replace the cables between the accelerator pedal and the computer. Has anyone else experienced this?
Thanks.

Does the check engine light come on when the problem occurs? If so, check the wiring harness that goes to the fuel rail temperature sensor; it might be rubbing against the engine block and causing a short circuit.

No, the injection fault light does not come on

Check the condition of the connector from the pedal to the computer; they corrode and cause problems. Be careful of humidity; sometimes you get on with wet shoes and it accumulates.

The cable from the pedal to the resistive accelerator is steel, like the others. I checked the connectors from the resistive accelerator to the computer, and I saw that the day before yesterday I was fiddling with them, and it didn't accelerate again. I checked the connectors. Question: Is it advisable to disconnect the battery when checking or cleaning the connectors?
Thanks.