Vacuum Leak Possible?

[Arrowshooter]

Got to thinking about some things while my truck is down with a bad fuel pump. One of those things is a pesky "ping" I have had since I replaced my intake gaskets. In the hills it gets real bad until the knock sensor takes over. I doubt that it is the timing because I made sure the distributor went back in lined up with the 3 marks I made. But I do have an oil leak in the back because I did a p--- poor job with the back bead of silicon. Judging by what my idle does when I take off the oil filler cap, could this be leaking enough vacuum to cause a ping?

[j cAT]

Originally Posted by Arrowshooter

Got to thinking about some things while my truck is down with a bad fuel pump. One of those things is a pesky "ping" I have had since I replaced my intake gaskets. In the hills it gets real bad until the knock sensor takes over. I doubt that it is the timing because I made sure the distributor went back in lined up with the 3 marks I made. But I do have an oil leak in the back because I did a p--- poor job with the back bead of silicon. Judging by what my idle does when I take off the oil filler cap, could this be leaking enough vacuum to cause a ping?

based on your statement this is most likely the cause.....when using silicone sealants it is very important to clean the metal with mineral spirits...any oil residue will cause sealant to fail....

[Arrowshooter]

Originally Posted by j cAT

based on your statement this is most likely the cause.....when using silicone sealants it is very important to clean the metal with mineral spirits...any oil residue will cause sealant to fail....

I agree, I think my problem came when the bolt holes were just a little off so I "scooched" it back.