Could be a number of reasons, rot, damage, vibration may have made it come loose.
Depending on where the leak is you just replace the vacuum hose or the bad part the hose is attached to.
You can have a vacuum leak on any hose on the vehicle but not on a fuel filter.
you can take oil and put it where you suspect there to be a vacuum leak. If there is a leak the oil will be pulled into the engine or hose
ck for vacuum leak at the pcv valve hose
To find a vacuum leak. the vacuum hoses should be sprayed while the engine is running. A solution of dish soap and water sprayed on a leaky vacuum hose will cause it to blow soap bubbles. Spraying both the hose and the connectors should find the vacuum leak quickly.
The vehicle does not have just one hose. A vacuum leak in any hose can cause low vacuum and the door will not operate properly. The leak could be under the dash or under the hood.
Usually a vacuum leak, check your power brake booster hose first, then any other vacuum line for cracks, breaks, or disconnection.
It could be a leaking vacuum hose to the power brake booster or the membrane in the booster could have a hole. When the brakes are applied, the booster is opened to the engine vacuum via the hose. The vacuum leak would then increase, causing the engine to stall.
The most typical cause of a vacuum leak is a cracked vacuum hose. The hoses get brittle with age, and cracks are common.
Broken or split hose Radiator leak heater core leak
Yes It Wil If The Vacuum Leak Is In A Hose That Gos To you Transmission
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