While on lunch break yesterday, some of the guys were talking about a guy they knew who has a new Porsche Carrera. They all agreed that he was nuts because he started the engine and then took off without letting the car warm up. The consensus seemed to be that he’s going to blow the engine out and ruin the car by not letting it warm up.
That got my attention because this past August I bought a Saturn Ion Redline, which has a supercharger. The guys I bought it from didn’t make any mention of letting it warm up, and I didn’t ask, because frankly I never thought about it.
IIRC, the Carrera is turbocharged. So is it different for a supercharger? Do I need to let the car warm up before I drive it, and if so, how long? I seriously love my car and don’t want to damage it in any way.
Thanks for your advice, which I know will be stellar as always.
The only thing I can really think of is that turbocharged cars often call for some higher viscosity oils (because the oil gets heated up by the exhaust in the turbo) and so an extra few moments to let the oil circulate before setting off wouldn’t be a bad thing. There’s no reason I can think of why you’d need to sit there and wait for the car to warm up though.
IIRC there’s no special oil requirement for the GM bolt-on supercharger engines like your Saturn’s, since with those there isn’t the issue of the oil getting heated up there. Letting the car run for a few seconds before you start out and waiting until it’s warmed up a bit before really putting your foot into it is a good idea on any car.
I’m just an idiot backyard mechanic, but I’ve heard basically the same thing that GreasyJack posted.
If you have a turbocharger, you need to let it warm up when starting and you also need to let it cool down before shutting it off due to oil temperature issues.
Superchargers don’t have that problem. You can start them immediately and shut them off with no special procedures and it won’t bother the supercharger at all.
What I have also heard is that on some cars, things like the knock sensors and timing adjustments don’t work properly until the engine warms up to close to its operating temperature. In this case, it can be a bit harsh on the engine to crank out the power with your supercharger as the engine timing will likely be a bit off.
The guys you overheard are repeating old wives tales. Actually what they are saying is contradicted by the guidelines in the owners manuals. You are just wasting fuel.
Letting an engine idle to warm up is not a good practice. It is better to have the engine under a low to medium load. The engine will warm up to operating temperature much faster this way. So, the best thing is to start driving right after starting the engine. But drive gently…light throttle and low revs at least until you see the temperature gauge coming up.
I have a Porsche, although a different model than the Carrera. Nonetheless, it clearly states in my manual that no warm up is required. As soon as the oil pressure sensor turns off the little red idiot light, I’m off.
Are “the guys” you are talking to older dudes? Maybe used to cars from back in the day when cars had carburetors? Warming up was more needed back then. Modern days cars with fuel injection don’t need a warm up. Just go.
I’d be surprised if any modern (<10yo) car with a factory turbocharger, up to and including the Carrera, needs any special treatment at startup and driveaway.
It is only good sense to avoid hard driving and hard engine use until the oil temperature comes up, but the days of factory/production/warranty cars needing babying at startup are long gone. There certainly was an era of mass-production turbo cars in the 1980s that were prone to all kinds of problems and early failures, but between better engineering, better lubricants and things like oil pressure reservoirs, even high-performance turbo engines are just “driveable.”
That said, I was at a concours a few years back, taking Best in Class with all the Italian exotics in the row behind me (where they belonged)… and some moron kept starting his Murcielago and immediately revving the shit out of it - maybe 6-7k RPM. The other owners and I kept looking at each other, and one finally said, “Maybe he has a tow truck over in vintage.”
Semi-ninja’ed: There is a difference between starting any car and driving away immediately and then driving “normally,” and the way a high-performance car might be driven. It is good practice to let any vehicle warm up before putting unusual strain on the engine and driveline, and moreso for anything that can rip up a track.
As for your FoF’s Carrera, back when there were carburetor chokes and single weight summer oils in colder, winter temps it may have been beneficial to let a Porsche sit for a minute before starting up. But I’ve read the owners manual and visit a lot of Porsche sites and they all say with modern fuel injection and multi-weight oil to NOT sit and idle first but simple start it and go. Now it probably wouldn’t be wise to push it hard until the water and oil come up to temp, which is around 175 and 210F respectively but on mine that occurs within about 10 minutes of normal driving. Also, for whatever it’s worth not all Carreras are turbocharged. Carrera and Carrera S use direct fuel injection. The Turbo (and rarer GT2) are pricier models and it’ll say Turbo on the rear, have larger air intake in the front, brake vents, etc.
ETA: What others have said about the supercharger.
There seems to be some middle ground here. No warm up is required, however you should drive gently till it is warmed up. I’ve seen some cars that show a blue warning light till the engine is up to temperature which is to indicate the time when you can do what you wish with the car.
So some form of warm up still seemed recommended, it’s just driving it till warm, instead of idling it till warm.
Thanks for the go-ahead. Yes, the guy who brought up the subject is middle-aged; the rest are younger, and they all nodded sagely, so presumably they just wanted to be thought of as super-knowledgeable.
The Redline does have an owner’s manual, but it’s not specific to the Redline, as so few were made; it’s just a generic Ion manual. I had to research online and finally email GE even to find out how much oil it takes (both for the motor and the supercharger). And of course the index was no help. I don’t know who indexes owner’s manuals, but as someone who used to index books, let me just say they really do a shitty job.
911s from the original model in 1963 up through 1998 had air-cooled engines. Turbo or no, it was generally considered unhealthy to rev them hard until they’d gotten up to normal operating oil temps and showed some CHT indication.
From 1999 onwards, Porsche switched to water-cooled engines for emissions reasons. Any concern about warm-ups pretty well ended with that changeover.
The issue as I understand it is the temperature of the turbine and turbine housing, i.e. the parts that have hot engine exhaust running through them. If you’ve just come to a stop after driving, then these parts have recently had very high temperature exhaust blowing through them, and they will be smoking hot. If you shut down immediately, the heat will migrate to the bearing section and roast the oil contained therein. Instead, the advice is to run at idle for a couple of minutes, moving relatively cool engine exhaust through the turbine (and fresh air through the compressor) to cool the whole turbocharger down enough so that when you finally shut down the engine and stop flowing oil through the bearing section, there’s not enough heat left to fry that residual oil.
Obviously this isn’t an issue for turbo engines on startup, and it’s not an issue for supercharged engines at any time (the supercharger being belt-driven instead of exhaust-driven). Even so, it’s a bad idea to mash the accelerator on any engine that isn’t reasonably close to full operating temperature. Pistons and rings aren’t up their designed fit, and you’ll get excessive blow-by past the rings, which damages all of those parts and also contaminates the oil.
Best bet of all is to consult the owner’s manual for your vehicle. Failing in that, the general advice is to idle for a few seconds, then drive away at light loads and moderate RPMs to warm up the engine before you start gettin’ jiggy wid it.
turbochargers get seriously hot when run hard and that translates to cooked oil, plugged oil lines, and loss of lubrication. Best to idle the engine for a bit after racing it.
While letting the engine idle to warm up is not necessary and just wastes gasoline, it does take 10-30 seconds after the engine starts for the oil to fully circulate. It is not a bad idea to let the engine run for 30 seconds or so after starting. With an automatic letting it sit in drive for 10 seconds or so before starting isn’t a bad idea, either. For a manual, 10 seconds or so in neutral with the clutch out will get the oil moving.
I will generally start the engine, then put my seat belt on. With my manual, I have it in neutral when I start it, and I just let the clutch out with my foot on the brake before putting it in gear. With the automatic, I’ll wait a few seconds after I put it in gear before taking my foot off the brake.
My brother will buckle-up, start the engine, drop it in gear, and start accelerating, all within less than 5 seconds after the engine starts. Drives me crazy.
Yes, it does. The oil galleries are full of air. While it is true that as long as you have oil pressure, the bearings are oiled, this doesn’t mean the oil has circulated, all it means is there is resistance to circulation. Giving the engine a few seconds to circulate the oil hurts nothing.
There is probably no downside at all to letting the engine run at idle for 10 seconds or so while you complete the ground-pilot’s checklist. The savings in fuel between turning the car on and then strapping on the belt, adjusting the mirror, tapping on the radio etc. and having your hand go from the starter switch to the gearshift is absolutely negligible. And while modern engines have full oiling and pressure pretty much from the first few turns of the crankshaft, it can’t hurt to let the flow get a bit better started, either.
None of this is about the trivialities of a few seconds here or there. Nor is it about how to treat cars that are pushed to the limit for a significant time. It’s about whether or not a reasonably modern turbocharged engine needs any special warmup before driving away, or any special cool-down after coming to a stop, and the answer to both is “no.”
IF you’re about the lap the Ring, letting the oil come up to temp is a good thing. IF you just outran a Highway Patrol in Nevada and made the Utah border in six minutes flat, you might want to let the engine idle a minute before shutting it off. IF you’re on your way to work or the grocery store, just drive the goddamn thing, no matter how low, wide, expensive, or multi-badged it might be.
OK, I’ve gotten you from “so long as the engine’s oil pump can move it, oil is flowing throughout your engine” to “1 to 2 seconds, at most”. Care to backtrack any more?
There are moving engine parts that are not oiled directly by the oil pump. These areas depend on oil being splashed or slung off of parts that are oiled directly from the oil pump. Things like cylinder walls, valve train components, etc… As different engines are designed differently, unless you have specific knowledge on a specific engine, it seems to me the prudent action is to let the engine run 10 seconds or so to make sure the engine parts are well lubricated. By 30 seconds, everything that needs to be oiled should be oiled.
Of course, it is also possible that I’m full of it.
No, but it sounds like your information is a few decades old, as discussed above. Engines have changed a huge amount decade by decade - after the dinosaurs of the 1960s and 70s, we had the frantically-modified crap of the 80s and early 90s… and then they’ve only gotten better every few years. Across the board, we now have more power, greater efficiency, vastly greater durability and generally “simpler” driving requirements than at any prior time, even ten years ago. (The cost is much more complex engineering, meaning most modern engines are not serviceable by DIYers or any untrained person, but oh, well.)
The changes in materials, engineering, technology, coatings, fluids and everything else mean that a 2015 Ford engine does not have to be treated like a 1968 one. Start it and go. It’s designed to do exactly that… and last twice as long, with a quarter the maintenance. The same is true of all but a few crapsters and a very few ultra-high-performance cars… and Porsches, frankly, are sold more to ignorant dicks who expect them to run like a German watch no matter how ‘badly’ treated than they are to street racers who prep their cars for every commute.
Start it and go. (Optional but good practice: don’t push it to any limits until it’s warmed up.) Park it and shut it off. Outside the 1% situations, nothing else is ever needed with any car newer than about 2000. It is what they are built, from the blueprints up, to do.
