Oro

A week ago I had codes 302,4,6 misfire and 1351 - generally a good indicator of oil control valve failure. 2002 w/247k miles. Car ran a little off and with reduced power over 2.5k rpms, though entirely driveable. All original parts; I cleaned the ocv filters and inspected/bench tested the valves a year ago.

So last weekend I pulled the front bank OCV, bench tested it w/12v. No issues apparent and valve appeared good on the bench. I found a great deal online for two new Toyota brand valves so ordered both despite the codes indicating it was Bank 2/front bank.

Today I put the front bank OCV in and there was no change on a brief test ride. Then I put the rear bank OCV in and all was good. The old one also bench tests ok - e.g. opens and closes fully with 12v across the leads. I view the bench test as an indicator it SHOULD work, but not a guarantee. I cleared the codes afterward and had 300 (generic misfire) as well as the 302,4,6, and also 1351 and 1354. Drove it a while after clearing and both new OCVs and no new codes.

SO: how does a bad valve in bank 1 result in a misfire across the front bank (2)? How does the PCU sense the misfires and VVT error? I've got to guess some sensor leads are switched. Perhaps the actual OCV leads? Not sure if they would stretch far enough to do that, but perhaps. But they appear to be power only - just two leads for power and ground to the electrical connector. Could the PCU sense resistance in the power lead from a a non-opening valve and generate a code that way?

You guys help me figure this out while I go change that pesky front hydraulic motor mount this afternoon...