Did I toast the engine?

[Jake Raby]

Originally Posted by Jager

Low oil pressure and AOS failure at the same time seems strange to me… Would loss of oil pressure cause a premature failure of the AOS?

Not strange at all.. Just a different mode of AOS failure. The AOS fails and direct manifold vacuum sees the crankcase in excess of 24" of water. This creates turbulence in that impacts the pool of oil in the sump, and pulls it away from the pick up tube, as well as creating extreme aeration of the oil.

Aerated oil has no ability to create pressure, and has no film strength.

Completely normal, and expected. This is by far the most harmful of the 4 ways that an AOS can fail.

The loss of oil pressure does not cause the AOS to fail, in fact the primary and secondary issues are inverted from that.

[Luckyed]

All the AOS failures I have seen resulted in white smoke. Is it common for the issue to sometimes result in black smoke?

[Jake Raby]

Originally Posted by Luckyed

All the AOS failures I have seen resulted in white smoke. Is it common for the issue to sometimes result in black smoke?

Yes, it can IF the manifold vacuum and planets align well enough to add fuel trim, resulting in excess enrichment, which leads to black smoke.

People think that every AOS fails the same way, thats not the case- symptoms and exact failure varies. I have seen AOS' fail and the engine never smoke at all, just make a vacuum squeak past the front main seal, and turn on the OP light, then fail like the original poster's has.

Because people don't know all the modes of AOS failure we see cars that are thought to have completely failed, and all they needed was an AOS. I have received these cars after plucking them off dealer lots 3,000 miles away, and fixed the issue in less than 1.5hrs.

That guy was told that he needed a 22K engine, I fixed it for 400 bucks.