W124 3.0 non idle surge
 

92 3.0 w 124 above 1500 RPM or 40 mph the car will speed up about5-10 mph without any increased pressure on the pedal.


205 k with new Head gasket,recent cap, wires, plugs, etc. I am thinking overvoltage relay as it has a used one that was installed about 20 k miles ago. Idle is stable with no lack of power or hesitation. Can you check these engines for codes successfully?

Kind of a vague problem description. Can you be more detailed? Is it possible the accelerator linkage is binding or staying partially applied?

The OVP will be the least of your issues, if it has intermittent problems, you'll have plenty of symptoms.

I know...when I worked at a BMW service dept. I hated when a customer would make a statement like I did . I replaced the gas cap which was a poorly sealing chinese POS and had a OVP relay so I swapped it out. The "symptoms" have seemingly evaporated.

Upon a discussion with my wife she said she used the cruise and that's when the symptoms appeared. I had some issues with the ASR linkage about 40 k ago and lubed and cleaned all of the linkages at that time. They still seem very responsive.

What would happen is the car would speed up like it had a defective VPS ( Veh. speed sensor) Idle is always rock steady and smooth throughout the power band. As my wofe says "It's like a hand would push you forward a bit and stop when you let of the accelerator"

I work in MH and gave my wife a full psych eval so she is good there ;-) The symptom only appeared 3x with me at the helm ......

I believe the cruise control does kick in at about 40 mph if I'm not mistaken. Might wanna check there, maybe disable the cruise control and take it for a spin and see what happens. Another thing could be throttle body, but I doubt it.