Making a very long story short, 157k mile 1987 fj60 2f engine was running crummy w. low vacuum (<10 in).
Determined a gasket leak. Determined cracked intake manifold.
New manifold assy installed, vacuum lines routing good, smog stuff good.
Here are the numbers.
Vacuum at 12 in with following compression/leak down data.
Cylinder # 1 -145 PSI, leak down within 10% (Good)
Cylinder # 2 -135 PSI, leak down within 10% (Good)
Cylinder # 3 – 132 PSI, leak down at 30% (excessive)
Cylinder # 4 – 145 PSI, leak down within 10% (Good)
Cylinder # 5 – 140 PSI, leak down at 30% (excessive)
Cylinder # 6 – 140 PSI, leak down within 10% (Good)
Need held in determining what's going on.
Why would only 2 cylinders have low leak down while compression good all around?
Is low vacuum associated with bad leak down numbers?
Would there be flutter in vacuum gauge readings?
All advice welcome!
Determined a gasket leak. Determined cracked intake manifold.
New manifold assy installed, vacuum lines routing good, smog stuff good.
Here are the numbers.
Vacuum at 12 in with following compression/leak down data.
Cylinder # 1 -145 PSI, leak down within 10% (Good)
Cylinder # 2 -135 PSI, leak down within 10% (Good)
Cylinder # 3 – 132 PSI, leak down at 30% (excessive)
Cylinder # 4 – 145 PSI, leak down within 10% (Good)
Cylinder # 5 – 140 PSI, leak down at 30% (excessive)
Cylinder # 6 – 140 PSI, leak down within 10% (Good)
Need held in determining what's going on.
Why would only 2 cylinders have low leak down while compression good all around?
Is low vacuum associated with bad leak down numbers?
Would there be flutter in vacuum gauge readings?
All advice welcome!