test

[paulmer]

Looping back — after installing the NGK 2288 plugs and doing a hard DME reset, the engine is much better. I'm still not 100% satisfied with idle quality, but it’s definitely improved. One objective piece of data stands out: fuel economy. On a gentle 70 MPH cruise, the OBC showed ~20 MPG. Even after a spirited drive, MPG only dropped to about 17. For comparison, I'm used to seeing ~7 MPG in city driving.


Next time someone complains about lingering issues on an M70 after doing the usual maintenance, I'll definitely start by asking them to confirm their plug resistance is at the correct 1kΩ spec.


Would it be wasteful to replace the fuel pressure regulators while chasing idle quality? Maybe I’m being overly picky, but I’m still not quite satisfied. The FPRs are the last untouched part of the fuel system under my ownership — everything else has been refreshed. I've also been chasing a phantom fuel smell that’s hard to reproduce. I'll probably change fuel hoses out of safety, but perhaps they could also be related to subtle idle quality issue? And if already changing fuel lines, maybe replace FPR, with consideration that internal rubber diaphragms may be many years old.


One other observation — during a smoke test, I saw wisps coming out of the DK throttle blades. Maybe it’s time to look into replacing those bearings. Between that and the plugs, maybe these are the twin smoking guns?

Thoughts, shogun?