Chapter 7- The Nicest Man With the Worst Car

The listing was on a neighbourhood app and Priya Anand sent it to her at ten past seven on a Tuesday morning with the message: isn't this the exact thing you're looking for.

Priya is a parent from the pickup line at Emma's school, works somewhere in the valley doing something involving data, and has an unerring instinct for spotting a good listing and no instinct whatsoever for evaluating one. It was, in fairness, the exact thing Sarah was looking for.

A 2019 three-row SUV. Seven seats. Ninety one thousand miles. Fourteen thousand two hundred, which was, by every listing Sarah had looked at in six weeks, roughly two thousand dollars under where it should have been.

Brant

Brant Willoughby was in his fifties, wore a fleece with the logo of a company he had retired from, and had the vehicle sitting in his driveway in Los Gatos with the doors open and the interior visibly, painstakingly cleaned.

He met her at the kerb with his hand out and an apology already in progress.

"I've had it running," he said. "Wanted it warm for you so it doesn't sound rough when you start it. Cold mornings, you know how they are."

It is important to say clearly what Sarah believes about Brant Willoughby, because the rest of this chapter is difficult and she does not want it misread. She believes he was doing what he thought was courteous. She has never had a reason to think otherwise, and by the end she was fairly sure of it, because of how he reacted.

But he had just told her, without knowing it, that she could not evaluate his car that morning.

The cold start problem

An engine is at its most revealing in the first minute after a cold start, and this is not folklore. It is a consequence of how the system works.

A cold engine runs on a different set of instructions. Fuel does not vaporise as readily, so more of it is delivered. The oxygen sensors are not yet hot enough to be trusted, so for a period the computer runs without their feedback and simply follows a programmed strategy. Oil is thick and has not reached everywhere it needs to reach. Clearances are at their largest. Some faults appear only under exactly these conditions: a weak ignition component that misfires until things expand into place, a seal that leaks until it swells, a sensor that reads badly until it warms.

Once the engine is at operating temperature and the computer has settled into its normal closed-loop control, the same fault may leave nothing at all to see. The car is not concealing it. The car has adjusted around it, which is precisely what it was designed to do.

Sarah scanned it anyway, because she was there and because she did not want to embarrass him. No stored codes. Warning light off. Self-tests mostly complete, with the catalyst and evaporative tests showing not ready.

Then she asked whether she could come back on Saturday morning, before he started it.

"You want to hear it cold," he said, and she could see him deciding whether to be offended.

"I want to see it cold," she said. "On the screen. It's a completely different set of numbers and it's the only time some of them exist."

Brant thought about this for a moment. Then he said, with what she is quite sure was genuine cheerfulness: "Well, that's more than the last four people did. Saturday. I won't touch it."

And he did not, which is the part that has stayed with her.

Saturday, eight in the morning

Frost on the windscreen. Sarah asked him to start it with her already sitting in the passenger seat with the adapter connected and the application recording.

The engine caught, ran unevenly for perhaps four seconds, and smoothed out. Brant, standing at the driver's door, said what people always say: "They all do that."

The screen did not agree. The misfire counters for two cylinders had moved during those four seconds, from zero, and then stopped. Nothing had been stored. Nothing was pending. The vehicle had noticed events and had not yet seen enough of them to commit.

That alone was a finding worth a conversation. What came next was the finding that ended the morning.

The code that cannot be erased

Sarah had got into the habit, by then, of checking one more screen. Most applications label it separately, and most people never open it.

There was one entry in it.

This is the single most useful thing in this book for anyone buying a used car, so it is worth stating slowly.

Vehicles built to the more recent revisions of the diagnostic standard keep a second, protected copy of certain confirmed faults. That copy is called a permanent code. It cannot be removed by the ordinary erase command that any scan tool can send. It cannot be removed by disconnecting the battery. It is cleared by one route only: the vehicle's own computer runs the relevant self-test again, under real driving, confirms that the fault is no longer present, and retires the record itself.

Read that against the situation in the driveway. There were no stored codes and no warning light. Somebody had erased the record. But the vehicle had kept its own copy, and its own copy said that a catalyst efficiency fault had been confirmed and had not since been proved fixed.

The unfinished self-tests, which had looked unremarkable on the Tuesday, now had a companion, and together they told a coherent story: the memory was cleared, the vehicle has not been driven enough since to re-run the slow tests, and the fault it was carrying has not been demonstrated to be gone.

Telling him

Sarah has had to explain a scan reading to a stranger a number of times now, and this was the first time, and she got it about half right.

She turned the phone around so he could see it and said: "There's a code on here that can't be cleared by clearing codes. It says the car confirmed a catalyst fault and hasn't proved to itself that it's fixed."

Brant looked at the screen for a long time.

"There was a light," he said finally. "Back in the spring. My guy said it was a sensor. He did the sensor and the light went off and that was that."

"Did he clear the code, or did the light go off on its own?"

"I don't know. I don't know what that means."

She explained it as carefully as she could. It is entirely possible his mechanic did a competent job. Replacing an oxygen sensor is a legitimate response to a catalyst efficiency code, because the code reflects a comparison between two sensors and a faulty sensor can produce it. Sarah knows this better than most people, because that is precisely what happened on her own car.

But the sequence matters. If the sensor was replaced and the code was then erased, the light goes out immediately regardless of whether the repair worked. The vehicle's permanent record does not go out. It waits, and it re-runs...

This curated preview is provided for personal reading. Copyright remains with Nobo Astoria.