Having problems with your 1997 Nissan Pickup ?
Brake pedal went out on me going about 65 on the highway, was able to pump enough to get it under control. Brake company said brakes and diaphragn were fine, needed new master cylinder. Brakes went out again on freeway going home even though they seemed fine on city streets. Took back a second time, they were supposed to have bled again. Brakes seemed fine driving on city streets, went out again at highway speeds going home. Last time on highway, no brakes, couldn't stop pumped brakes so slowed
It sounds like you've got an issue with the engine vacume line going to the booster. there's an in line one way check valve that keeps vacume in the booster in case of a loss of vacume, like if your truck stalled while driving. but there should always be vacume with the engine running. so check the vacume line going to the brake booster for kinks obstructions, and leaks.
Repair Help & Product Troubleshooting for 1997 Nissan Pickup
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