Its been several years since I've mined the combined knowledge of the friendly and knowledgeable members of this forum, and today I have a QUESTION: Is it possible to disable the vacuum assist part of the brake booster? That is, plug the hole on the front of the brake booster where the check valve plugs in, and plug the vacuum line at the other end where it comes out of the intake. Why would I consider this foolishness? Because I don't want to buy and install a new brake booster that's why. New brake boosters are expensive. And I hate crawling under the dash to get at the 4 bolts that hold it to the firewall. I don't want to pull one from the junkyard either...who's to say it would be any better? I just put on new calipers and a new master cylinder. When the engine is not running the brakes are hard as a rock. When the engine is running the pedal is going pretty far down before we get to any braking. I want them solid, not mushy. Anybody ever try this? Does anyone understand the "theory of operation" of the brake booster vis-a-vis the brake hydraulic system? Art Benstein, the one true authority on matters concerning the 240 Volvo, what do you think about my idea of disabling the vacuum-assist? Yes, I am just a shade tree mechanic, but the wheels haven't fallen off so far. The car is a 1988 240 DL with approx. 230,000 on the clock.