Volvo: volvo 940 turbo, volvo service, volvo 940

Question
Morning,


I have 2 potential problems with my Volvo 940 turbo 1994 with 121 k and full Volvo service history.

Firstly, when I press down on the break pedal before I start the engine it is firm, I then start the engine and the break pedal relaxes slightly and I can then press down on the pedal further, this is normal I believe.  Recently, the break pedal has remained firm on engine start up and doesn’t relax.  The pedal doesn’t try and force its way up to resist my foot, it just stays firm, any ideas?

Secondly, on warm start up, the engine revs start higher than normal about 2000 rpm but stays there for about 10 to 15 seconds and roughly settles down.  Normally it would start perfectly at about 1500 rpm and the settle as normal, any ideas?

Please let me know if you can help.

Thanks

George


Answer
George,
Have the brake booster, and check valve tested for leaks. Vacuum should be applied to the booster when the vehicle starts. As the idle, sounds like the brake booster or valve leaks, that sometimes causes a high idle. Clamp off the hose to the booster, start the car and see if that works to verify a leaking booster or valve.