Stiff Brake Pedal on Cold Start - already replaced valve and gasket
#1
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So I've been fighting this for at least the past 3-4 months now. I've already replaced the gasket and the valve assembly on the master cylinder with no improvement. I even put a few hose clamps on both ends of the hose that goes from the valve assembly to the intake manifold to rule that out, but I'm still getting that stiff brake pedal. I've also noticed a bit of a shudder at idle recently too, I'd like to say there's a minor vacuum leak somewhere but I've had no luck in tracking it down. I can hear a air hissing type of noise behind the manifold, but I'm pretty sure that sounds like its the PCV valve.
Does anybody else have any ideas to what I can check?
Does anybody else have any ideas to what I can check?
#4
Lexus Test Driver
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If you want to confirm PBB islate it by plugging the hose and start the car. Do you still hear a hiss??
Next step. Get a hand held vacuum pump and rig some sealed plastic fittings to the PBB and pump away untill you pull a vacuum on the booster. If all is well it will hold that vacuum for days.
Id say use soapy water to look for leaks but its not going to blow bubbles, just suck your suds in. If you have a huge vacuum leak propane will make the engine raise its idle but thats big leak.
Next step. Get a hand held vacuum pump and rig some sealed plastic fittings to the PBB and pump away untill you pull a vacuum on the booster. If all is well it will hold that vacuum for days.
Id say use soapy water to look for leaks but its not going to blow bubbles, just suck your suds in. If you have a huge vacuum leak propane will make the engine raise its idle but thats big leak.
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