2002 Seville SLS question: PCM P0106 Code

[dwhitcombe]

Yesterday as I was coming into Denver, descending a mighty hill (10,000 feet to 5200 feet in about 40 miles) I was making use of the cruise control and downshifting to keep the car at right around the speed limit and avoiding use of the brakes.
The tachometer was reading pretty high in 2nd gear, and I tapped the cruise to decrease speed about 3 miles / hour, and the "Service Engine Soon" light illuminated almost immediately.
I pulled codes this morning, and got P0106 - Manifold Absolute Pressure system performance.

Did I break something?

The code wasn't current this morning, so I'm assuming the car isn't worried about it after getting into Denver and driving around happily for 2 or 3 hours, and after I reset all codes, it hasn't thrown the code again.

I'm assuming that the high rpms, the high altitude (probably around 8000 feet above MSL at the time the code got thrown) and fiddling about with the cruise control all contributed to the throwing of the code.

Can anyone contribute something I can take away from this? Should I take it into the Auto Shop (I'm a high school teacher, and we have a really excellent auto program)?

Thanks!

(First time poster, long time leecher..)

[Ranger]

Probably just a high altitude hiccup as you said. I would not worry about it unless it happens again.

[submariner409]

MAP (Manifold Absolute Pressure) is the inverse of atmospheric pressure: with the engine OFF MAP is 14.7 (psi) at sea level. Running, MAP varies as throttle opening and engine load changes, and is then a measure of varying manifold vacuum. Total vacuum is 30" of mercury (mercurial barometer) so MAP can be mentally converted into vacuum by doing an inverse 2 : 1 mental conversion - MAP 5 is about 66% of 14.7, so 66% of 30 = about 20 inches of vacuum. Manifold vacuum is greatest at idle (throttle blade closed) and least at WOT (100% throttle) so atmospheric pressure is pushing air into the engine as fast as is possible - the engine does not "suck" air.

Long-winded explanation for "Your light was normal under the circumstances".

Some who fool with MAF's and so-called "cold air intakes" wind up with all sorts of mixture and MAP codes.