Let's say im parked and the car is on , if it stays like that for a while , does it damage anything ?! my friend insists that it ruins your engine because it stays in the same RPM area . any help is appreciated

Thanks

 

if its like that for maybe 20-30 mins and u have the **** modded out of it it may overheat.

other than that i dont think so.

(unless your talking about a new car with the engine not fully broken in yet.)

 

The thing i heard was that the engine does not have enough cooling because normally it would be cooled by the fans and coolant moving at higher rpms and/ or the wind coming at the car at high speeds.
I have stayed in my car for a full 3 hours waiting ... it was hot outside. I dont see or feel any deterioration in performance of the engine or the a/c for that matter.

 

But the fan should activate once it detects a determined temperature no?

 

yes the fan would be activated. though i heard that the tranny can get quite hot running idle.

in any case, for modern cars, i don't see any problem except that you are killing environment bad

 

There of course, is some added heat buildup during hot-weather idle, but electric fans have generally solved the lack-of-airflow idle problem with the old cranksaft-driven fans. In addition, many A/C equipped cars have a second fan as well that comes on with the compressor or at a predetermined coolant temperature.

One thing that is important.....the old rule about shifting into neutral and raising the idle speed during overheating does NOT apply any more to modern electric-fan cars. Unless you are driving an old car with a crankshaft-driven fan, toss that idea out in the trash. Electric fans are NOT affected by engine RPM and will generally spin at the same RPM no matter what engine speed is. And if you DO rev the engine you only make it worse.....the engine then produces more heat with the same fan speed.

Another old idea that can be tossed out, particularly if you have a second fan, is turning the A/C off. Keeping it on often activates the second fan and adds secondary cooling. If you shut the A/C off you may lose this secondary cooling.

Those old ideas worked with yesterday's cars but won't with today's.

 

the engine isnt generating extra heat because its operating at low rpm cooling isnt an issue. Idling for extended periods of time just wastes gas, the rpm is so low theres very little stress on the engine

 

On most 4-cylinder engines, especially those without balance shafts, idle RPM is actually harder on main crankshaft bearings than moderate engine speeds because the cylinders don't fire as smoothly at idle and the vibrations get transferred by the connecting rods to the bearings. Toyota and Honda fours, however, are especially smooth at idle...more so than some competitor's V6's.

 

Not much different than cruising at 60 on the highway at a consistent RPM in the final gear. You won't hurt the car as long as your cooling system is in good condition.

The thermostat dictates this, and will activate the fans at a given temp.

 

I use my cars as mobile offices at least one day a week - meaning that I may spend 30 minutes at idle two or three times a day in cold or hot weather to keep the HVAC running. As mmarshall said, with the old engine-driven fans, you had to keep an eye on the temperature gauge. I found some of the early US made cars with electric fans also had some problems as the thermostat logic wasn't fully sorted.

I had an '84 Olds Ciera and an '86 Buick Century company car that would often switch on the cooling fan several seconds after you shut down the engine, locked and walked away from the car . . . always gave you a creepy feeling that it would kill the battery because it would often run for several minutes. It was not uncommon to see the coolant temperature rise and fall over a fair (uncalibrated) range during extended idle periods.

Today's cars are a whole lot smarter. I hardly ever see the temperature gauge move once the thermostat is open. Extended periods of idling, particularly with today's high-detergent gasolines, do not produce the fouling problems of their predecessors - however it is still a good idea to get out on the freeway for a good half-hour's run before shutting down for the day. Whether it helps or not, it just makes me feel better.

 

Something else in the car (especially fluids) have to be worn down first, and then idle can cause some issues. I know one incidence where someone left their old late 70s Mustang in idle (the fluid probably was bad before) and the tranny did give out after he waited 45 minutes in idle. My cousin had to go fetch him with a flatbed.

 

Thanks guys for the input CL rocks