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Okay here's the deal:
The 4 valve/cylinder engines use small valves and the accompanying lighter valve springs. The exhaust valves will on any engine get some accumulation of deposits, primarily from fuel combustion with some portion from oil that seeps through guides for valve stem lubrication, that in some situations can cause the valve to slightly bind in guide.
On a cold engine the guide-valve clearances are reduced due to temperature and the fact the metals of guide and cyl head shrink more than the metal of valve stem. You attempt to start engine and the oil system can and does build oil pressure on these engines in one crank revolution. This leads to the hydraulic valve lash adjusters ("lifters") filling and extending ("pumping up") while the sticky valve is closing sluggishly and not following the cam profile.
1. A strong contributing factor is excessive fuel system cleaning additives. I know this flies in the face of what has been said loudly and often for the last few years but it is the truth according to a recent study on this very no-start, low compression problem. The additives used for fuel system cleaning make the deposits on exh valve stems worse.
If you don't have a fuel system problem with symptoms then don't add anything to tank in the form of a cleaning additive.
2. Premium fuel has lower volatility and is harder to ignite in cold weather. This can make engine not fire as strongly on initial cranking and less than stellar starting performance give the "lifter" pump-up problem time to occur. If the engine fires off and reaches speeds over 600 RPM the lifter filling time is lessened enough to diminish the odds of the pump-up.
Cold weather also reduces the need for higher octane anyway as spark knock is less likely in colder air temps.
3. Regular operation of the engine at eng speeds over 4500 RPM for 5 minutes or more will cause valve rotation that will clean stems of valves somewhat. This can be done by driving with cruise set in "L" position on gear selector at 55 MPH. THIS WILL NEVER HURT THE ENGINE! QUITE THE CONTRARY, IF YOU DO THIS, I GUARANTEE YOU WILL NOTICE A SMOOTHER IDLE WHEN YOU STOP AFTER THIS EXERCISE OF ENGINE!!! I was amazed at the difference when I tried this on my parents' 95 960.
If the no compression, no start condition occurs you can usually get it to start if you will keep your foot on throttle 1/4 open and operate starter for 30 seconds at a time with a 1 minute rest. Keep throttle open until it starts. If 6 attempts (3 minutes starter time) have been made and it is not running then you will have to have a tow to a service shop. If cranking speed becomes slow during this time indicating you have a severely weakened battery, stop and charge battery or give in and have it towed to service shop.
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