throttle dies when brake pedal depressed

frankjones48 · Post by **frankjones48** » 07 Oct 2012, 12:06

2000 s80 t6, 140,000mi. When brake pedal is depressed, the accelerator pedal becomes useless or dies. Any speed or at idle.
Car idles fine and accelerates fine but, when brake is depressed all revs above idle die. What could this be?

Post by **boosted5cyl** » 07 Oct 2012, 13:31

Sounds likeyou might have a major vacuum leak either at one of the many vacuum pipes, or perhaps on one side of the brake booster/servo itself. Time to start hunting for a leak!

frankjones48 · Post by **frankjones48** » 08 Oct 2012, 12:15

actually, the throttle dies when the brake light goes on(no pedal pressure). So- 45mph down the road - touch the brake to indicate slowing down -throttle goes to idle. Where to begin? Thanks for any replies.

Post by **boosted5cyl** » 08 Oct 2012, 12:31

Have you been able to verify this by manually pressing the switch by itself? I get what you are saying but I would want to be 100% sure myself.

How's your battery voltage at the terminals while the car is in use? All lights on, radio on. blower on etc etc? I don't think that the battery is necessarily the cause of your problems but since these cars are so reliant on electronics I would start by making sure the voltages are stable..

frankjones48 · Post by **frankjones48** » 09 Oct 2012, 11:24

Thank you for your reply. No, I haven't just depressed the switch which I will do and let you know. I have replaced the voltage regulator and the battery within the past week as that was necessary but, the problem remains.

Post by **boosted5cyl** » 09 Oct 2012, 11:52

Cool give it a go and report back. No idea what's going on to be honest but hopefully we can figure it out.

ACk · Post by **ACk** » 13 Oct 2012, 15:25

Hi, check the main vacuum hose with the check valve from the brake booster to the intake manifold. check the fuses for the brake system and ABS system. See if you can smell any burning from the main relays in the fuse box. check to make all the bulbs inside and outside are not burnt, or appear lose in anyway. Look for yellow/black burn marks, you may have a short somewhere.
If you or a friend has an OBD meter, plug it in and see what it reads.

Drive safe!

frankjones48 · Post by **frankjones48** » 17 Oct 2012, 08:31

Have been on vacation but, back now and am on it. Thanks for the responses.

Frank