Why Does My Car Run Better When Used Frequently?

[rwest]

Hi,

I know that many of us are fond of saying these cars are meant to be driven; I agree, and mine when not driven for several weeks will back fire upon start up and then maybe even the next few starts, but if I drive it or run it every day or every couple of days, I don't get any back fires. Can anyone supply a reason why?

Thanks,
Rutager

[spuggy]

Originally Posted by rwest

Hi,

I know that many of us are fond of saying these cars are meant to be driven; I agree, and mine when not driven for several weeks will back fire upon start up and then maybe even the next few starts, but if I drive it or run it every day or every couple of days, I don't get any back fires. Can anyone supply a reason why?

Thanks,
Rutager

Because it resents you when you don't use it...

Seriously, the platform was developed in/by/for endurance racing. Try a LONG drive. Like multiple hours, stop for gas, keep going. Like Seattle to San Diego.

It'll probably run better after that than you've ever known it run before. For at least a week...

[Dave Colangelo]

Engines are designed and tuned to run, statues are designed to sit around. I have thought about this many time and this is what I will throw out feel free to criticize.

Engines are tuned and designed to run and thus that is where they are happiest. when things sit, the air around them is stagnant and gravity is pulling down on them. Thus rust may occur from moist air sitting around an engine, things may settle into place while they sit for to long. Oil may gum up on small parts spark plugs may get corroded, the fluids will settle and separate, you get the picture, and lets be honest these cars have a heart and soul, they get offended...

Regards
Dave

[mreid]

I thought I had a great answer until I read Dave's.

What he said!

[drodg]

When my 911SC sits for numerous weeks the suspension is noisy, the doors creek and it doesn't sound like the solid structure that I know it is. I drive it and everything gets quiet. I drove it a few Saturdays ago after it had to sit for numerous weeks because of our lovely midwest winter. I pulled it out of the drive and thought what is wrong with my car. Why all the groans? After driving it everything settled down and I thought now that is why I love a 911!

[911SauCy]

After sitting through the winter, mine is a grumpy beast for about 150miles.

Then, it begins to run and react in a more composed manner to everything...and BEGS FOR MORE!

[mhunter]

I like to add to this thread since I was thinking the same thing. I've had my Porsche 1971 911t for 16 years and I always drove it on weekends. It always had that burning oil smell, probably from oil leaking on the heat exchangers. For two months now I've been driving my Porsche to work everyday and the burning smell of oil has become unnoticeable. I also think it runs better too. My car really does liked to be driven daily. after all these years Im getting to know my car.

Mh

[McLaren-TAG]

You guys let your car sit long enough to ponder about it?

[Canada Kev]

How do you feel after sitting on your ass for a few weeks and then go out for a run? Make a few groans and get some muscle aches? After a few regular runs you start to feel better and actually look forward to them, right? Same with your 911. She just wants a bit of exercise...

[rwest]

All good points, I have taken my car on several 24 hour drives over the years, only stopping for fuel and nature breaks; oil consumption was very low, I'm sure because all the parts were expanded perfectly to each other.

As far as letting it sit for long periods, being in MN, I don't have much choice if I want it to last. I have a mildly heated garage and I run it to temp every few weeks if outside temps get above 30.

I'm still curious about the back fires, maybe it takes longer to crank and more raw fuel gets into the airbox?

Thanks for the responses,
Rutager

[neilschelly]

Regarding backfires, maybe you've got a fuel injector with a slow leak? That would cause those first few revolutions to run a bit rich and some extra fuel to slip through to the exhaust.
-N

[T77911S]

i think its worse for high mileage cars to sit.
my volvo, 150k+ sat for 2 weeks. its was vine when i parked it but had all kinds of alarms going off when i started it back up. ABS, was one of them..

my mercedes has been sitting for a month. 170k. i hate to see whats going to be wrong with that one

[theiceman]

i dont experience any of this .. Maybe its just me .. in fact the sounds and smells of rolling my car out after 6 months of hibernation are amazing.

It may take a couple of extra cranks to get it to go in the spring but thats it . Once started it purrs and goes like it always did ..

[Canada Kev]

Where I live it's gotta be stored for the winter. I've found that actually UNheated (well below freezing) storage ALL winter without starting it up seems to work very well. Other than a bit of extra cranking and a small amount of smoke on the first start of the year, she runs great with no hiccups.

[tharbert]

I wonder if some of this sentiment isn't a result of ethanol. Our cars were never designed for it's use. It shouldn't be left unused for more than a couple weeks. It has some terrible attributes, some magnified by age: hygroscopicity, phase separation due to exposure to water, different solvency characteristics that loosen debris in the fuel system... Just a thought.

[manbridge 74]

Check the basics.

I've had my car for two years and once everything was dialed in as it was intended to function per the people who designed it... no more erratic starting/running.

One caveat regarding fuel today vs 1974. Besides ethanol (or maybe because of it) concerns, today's fuel has lost some of its lubricity. This is of concern to CIS guys and why you see threads about adding Marvel oil or ATF to gasoline.

[ASD]

guitars are meant to be played..they sound better, feel better. Cars are meant to be driven. Charging the electricals, warming the metals, oiling, exhausting, moving, it all flows. People shouldn't sit on a couch too long either....

[manbridge 74]

Agreed. But for those that live in areas with winter/salt/gravel I don't think it's too much to expect instant fire up after 2-3 months. I get a bit of smoke for the first quarter mile, (normal for these cars after storage) but everything functions normally.

[bcgreen]

After sitting, are there any issues with leaks?

[manbridge 74]

Oil leaks- yes. But...

My plan is to follow what I've learned via air/oil cooled Suzukis/Yamahas. If they did not leak when I owned them, neither should a 911. Just haven't had the reason to drop the engine yet to address them.