Brake pulsing sensation??

[F4Phantom]

I drive along and after the car is warmed up I feel like the brakes are being very slightly applied and so get a faint deceleration on and off pulsing feel from the car. If you were to manually simulate the feel by using the brakes you probably couldnt because its light, so I dont think its the brakes.

If anyone knows what this could be please let me know.

Thanks.

[genphreak]

If not I'd suspect an air intake leak. Have you checked the non-return valve pipe is sealed? However the leak could be elsewhere, or it might be a sticky ICV- if the solonoid is a little sticky it might do this.

Does the engine feel like its idling smoothly? :) Nick

[F4Phantom]

If not I'd suspect an air intake leak. Have you checked the non-return valve pipe is sealed? However the leak could be elsewhere, or it might be a sticky ICV- if the solonoid is a little sticky it might do this.

Does the engine feel like its idling smoothly? :) Nick

In terms of the engine running smooth, it does, but another possible linked symptom is that after the car is warm, I can sit at the lights and put it in neutral, and the rpm will climb steadily to say 1100rpm. it will always drop eventaully back to normal idle. But you can feel in 'D' it has more urge so putting in neutral tells you how many rpm the engine wants to do. Obviously this is impossible to notice while driving because you are always doing more than 1100rpm. So the two symptoms are the idle is smooth but the rpm changes, and the pulsing thing.

[Cavs]

Possibly the air flow sensor?

[BillionPa]

your idle shouldnt fluctuate by more than +-70rpms when warm, if its climbing you probably have an air intake leak, check the intake boot after the air flow sensor, and if needed get a smoke test done.

[F4Phantom]

your idle shouldnt fluctuate by more than +-70rpms when warm, if its climbing you probably have an air intake leak, check the intake boot after the air flow sensor, and if needed get a smoke test done.


OK thanks I will go and see to all these potential problems. I might wrap some tape if I see a hole and see if that fixes the prob.

[Jon K]

sticking caliper? compare all brake pads to one another

[F4Phantom]

sticking caliper? compare all brake pads to one another


Hey I just realised, on the rear one side of the pads are much thinner than the other side. Could this be it? POSSIBLE BREAKTHROUGH!

I just thought it didnt matter with auto leveling calipers.

[genphreak]

Hey I just realised, on the rear one side of the pads are much thinner than the other side. Could this be it? POSSIBLE BREAKTHROUGH!

I just thought it didnt matter with auto leveling calipers.Rear only? This shouldn't happen. ON the rear, if you get a real bodgey mechanic, they might only replace one pad as they sometimes don't realise the calipers come apart. Without taking them to bits you can get the old pads out, but you can only replace one pad due to the new pad's greater material thickness...

F4, I would test drive the car rolling in neutral before you get too excited. Major source of vacuum leaks is the sump gasket- perhaps the front oil timing cover is a possibility too...

The AFM output needs to be tested against a ohmmeter for a steady resistance rate of change. ICV needs to be checked for smooth operation back and forth at 5V.