How to tell if the intake gasket is bad on the "inside"?
Thread Starter
Supreme Member
Joined: Aug 1999
Posts: 2,441
Likes: 1
From: sweden
Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
How to tell if the intake gasket is bad on the "inside"?
Hi..
Is there any easy way to test if the intake gasket is leaking on the inside of the engine?
/N.
Is there any easy way to test if the intake gasket is leaking on the inside of the engine?
/N.
Supreme Member
Joined: Apr 2002
Posts: 1,353
Likes: 3
From: Austin
Car: 82 Z-28
Engine: 383 TPI
Transmission: 700R4
Actually there is a way. Remove the breather and PCV from the valve covers. With eng idling (cold eng would be more comfortable) plug the breather and PCV holes with your palms. If you feel a vacuum building, you have an internal vacuum leak.
You can tape one of the holes and use your hand to seal up the other hole if you prefer. Might need to tape over the oil cap hole if the oil cap is venting. Main idea is to seal off the crankcase so you can tell if a vacuum is building up. It may take several seconds for you to feel the vacuum. Depends on how big the vacuum leak is.
Internal vacuum leaks are pretty rare, but when they do occur; they are almost always misdiagnosed. Luckily they are easy to check for.
You can tape one of the holes and use your hand to seal up the other hole if you prefer. Might need to tape over the oil cap hole if the oil cap is venting. Main idea is to seal off the crankcase so you can tell if a vacuum is building up. It may take several seconds for you to feel the vacuum. Depends on how big the vacuum leak is.
Internal vacuum leaks are pretty rare, but when they do occur; they are almost always misdiagnosed. Luckily they are easy to check for.
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
May 10, 2023 07:19 PM
ambainb
Camaros for Sale
11
Apr 25, 2016 09:21 PM
