Serious Problem
03-04-2011, 05:39 AM
#16
Rennlist Member
One thing first:
The Power assisted brakes works by getting vacuum from the plenum chamber.
No el connections, No fuses, No alarms - No nothing.
Your brakes are working perfectly fine without the power assist, however the pedal is heavier..........
There is a hose going from the plenum chamber to the brake booster. If there is a leak here it will result in two things:
1: Loss of power assisted brakes (Brakes still works perfectly)
2: Will cause a rough idle / running issues, as the engine will draw unmeasured air.
The Power assisted brakes works by getting vacuum from the plenum chamber.
No el connections, No fuses, No alarms - No nothing.
Your brakes are working perfectly fine without the power assist, however the pedal is heavier..........
There is a hose going from the plenum chamber to the brake booster. If there is a leak here it will result in two things:
1: Loss of power assisted brakes (Brakes still works perfectly)
2: Will cause a rough idle / running issues, as the engine will draw unmeasured air.
03-04-2011, 05:48 AM
#17
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993turbo:
just checked board and yes- there are no fuses etc.
I did notice that the rubber cap that is normally on top of the plenum was off and sitting on the engine!
Can you tell me where the hose is?
just checked board and yes- there are no fuses etc.
I did notice that the rubber cap that is normally on top of the plenum was off and sitting on the engine!
Can you tell me where the hose is?
03-04-2011, 05:55 AM
#18
Rennlist Member
No sure how its routed on a RHD car as your brake booster is on the opposite side of NORMAL cars.
However, if you know what your brake booster looks like: (BIG round black thing) on the drivers side firewall. There is a air hose going from the brake booster to the engine. This hose must be verified.............................
However, if you know what your brake booster looks like: (BIG round black thing) on the drivers side firewall. There is a air hose going from the brake booster to the engine. This hose must be verified.............................
03-04-2011, 06:51 AM
#19
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My love for Rennlist knows no bounds!
Found a fat black hose with a connector that had come out. Plugged back in and I have brakes that work without all my weight!
So, two unrelated problems that occurred at the same time, as per sod's law. I suspect the dodgy roads here on the Isle of Wight, including a drive up 2 miles of unmade road to see a friend in the middle of nowhere, shook the hose loose.
Thank you everyone for your help. How could a fool like me fix such a complex car without this forum?
Mrmerlin interpreted my panicked rambling straight away- hats off to you, Sir. I will have to get to the bottom of the weird starting issues that another time. Hopefully car will be fine for funeral this afternoon, plus trip to Bristol tomorrow before returning to London. Perhaps John Speake can be persuaded to look at the system.
I have also learnt about the brake system on the 928 today...
So, two unrelated problems that occurred at the same time, as per sod's law. I suspect the dodgy roads here on the Isle of Wight, including a drive up 2 miles of unmade road to see a friend in the middle of nowhere, shook the hose loose.
Thank you everyone for your help. How could a fool like me fix such a complex car without this forum?
Mrmerlin interpreted my panicked rambling straight away- hats off to you, Sir. I will have to get to the bottom of the weird starting issues that another time. Hopefully car will be fine for funeral this afternoon, plus trip to Bristol tomorrow before returning to London. Perhaps John Speake can be persuaded to look at the system.
I have also learnt about the brake system on the 928 today...
03-04-2011, 08:00 AM
#20
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,<snip>
03-04-2011, 09:56 AM
#21
Team Owner
FWIW I would at the least check the ground strap at the rear of the car and take a peek at the hot post under the hood.
These are easy things to look at you might find a loose or dirty connection and it will take only a few mins to fix.
Kinda weird how 2 things fail at the same time glad you figured out one of them
These are easy things to look at you might find a loose or dirty connection and it will take only a few mins to fix.
Kinda weird how 2 things fail at the same time glad you figured out one of them