Not the typical "Warm up", The Owners Manual says Options

[Gunn1]

It isn't the first time I have read the 75' 914 1.8/2.0 operating instructions manual, but for some reason this time around this instruction struck me as odd.

Only because coming from a colder climate we typically start our autos and let them "Warm up".

However in the Starting the Vehicle section on page 29 it states;

"Do not warm up the engine in Neutral. Drive off Immediately using only low engine rpm for the first few miles"

I do understand keeping the RPM's down until everything is warmed up, but why would the book ask you drive off immediately? always thought even in Mild temps it was advisable to let the engine and fluids in the transmission warm a little before driving.

What reason would there be for not letting the engine warm up in Neutral?

[jcd914]

It is purely for emissions.
The emission compliance testing includes any and all warm up required by the manufacturer in each test run. Emission for compliance testing are measure in units per mile over a designated test run, on a dyno and the capture and measure everything from the tailpipe from the first turn of the key until the engine is shut off. Any emission idling is part of the test and up the per mile values. They also capture and measure fuel vapor loss.
So the manufacturers all eliminated the warm up cycle.
They didn't really change anything, just the warm up instructions.

Most aluminum pistons of the era have steel reinforcements in the castings. With the different expansion rates of the two metals the pistons are not round until they reach normal temperature. There are other engine parts that also need to get to temperature before the function as designed, oil being one of them.

Are you going to hurt it driving easy while it warms up, probably not.

But no engineer thought this up and decided it was "best" to drive off immediately.

An engineer calculated have calculated the impact the idle time would have of the test values and some manager would probably have received a bonus for the savings of not adding more emissions equipment.

Jim