Idling damage

[TDot]

For the past year I've been idling my car A LOT while doing my audio set up and doing computer programming for my front end for my computer. While doing research on how to calculate gas burn during idling I found out that idling can damage your engine. I have noticed that the car has been driving a little rougher, noticeable to me, and don't really understand why, so for now ill attribute it to excessive idling since finding this out. How much is excessive? Just so I'm clear, up to 4 hours at a time.

So my question is, although extremely general, how do I go about repairing damage caused by excessive idling if nothing is standing out? What would you look to fix or change that could have been warn or damaged due to idling? What first? And tell me the rough cost because I'm not an engine guy. Thanks.

[EniGmA1987]

The biggest thing I see on modern cars about idling being damaging is the argument that if the car idles for long it wont be running at optimum temperature, which causes the fuel not to burn all the way , which then coats internals and so on and so forth. This is not the case in our cars, you can idle our car for hours and it will be at 90 degrees Celsius the whole time (well, after warm up anyway). You can drive normal around town for hours straight and the car engine will be at 90-91 degrees the whole time. The radiator will speed up or slow down its fans to help regulate temps very well.
The second argument I see most often from searching is that modern cars run rich when idle, which is not true of our car either. If you look at logs from the engine you will see that when idle the A/F ratio is right about 14.7:1 which is the perfect balance for cleanest burn. I really dont see how idling can actually damage the engine in our cars.


You could always seafoam your engine, then change your spark plugs just to be sure, and also maybe clear your learned fuel settings for the car. And do a few really good hard pulls up to redline to help clear things out.

[TDot]

Good to know, thanks.

[svard75]

That is why they created the italian fix it where you basically race the car hard so that it cleans out all the sensors and the buildup. I would perform the three resets first before you go blaming the idle. You would be quite surprised.

I forget which three things to reset but it's basically the idle air, ecu and pedal setting. That made a huge difference in my cars idle feel.

[TXT]

I'm no expert, but I feel the same way when I idle my car. Reason being is my M45 burns oil which I have come to accept. It has not gotten worse in the 2 years I've had the car.

An argument was made before somewhere that an "Italian tune-up" does nothing to a car and will not clear up any carbon build up. I would assume that idling a car will just build up a bunch of carbon deposits since the car has no chance to clear it out when the RPM's go up and down. I think 4 hours is excessive and I wouldn't do it but obviously you had a reason to do it. If you want a good answer, I suggest you look up on Google or whatever preferred search engine you use, and look up used police cruisers and the questions of idle times those car's see. People try to buy used police cruisers and the idle time always comes up.

Enigma probably has best solution to ease your mind. Change spark plugs but before you do that, run some seafoam! According to the manual, my car does not need spark plug change till' 105,000 miles so that's when I will do mine, coming up soon. I am expecting and hoping that my car will run much better even though I feel like the car is fine now....always room for improvement.

[Mjkkb2]

How much is excessive? Just so I'm clear, up to 4 hours at a time.

Holy Cow - that's a long time to be getting 0 MPG. Yikes!

[svard75]

TXT - there are opinions for and against the Italian tune up but what I experience is the real deal. When I drive mostly city day to day I often am stuck in bumper to bumper traffic where I barely reach 20 mph. Then once per week I hit the highway and start the car down around 80 floor it to 140 and repeat 3-4 times. Each time I do this I hear the engines tone changing. The first run sounds rough and raspy. Second a bit less etc and each time it feels stronger. I've validated this with my up rev tuner. He confirms that by driving the vq35 engines at constant idle carbon deposits build up and oil deposits as well. Running it hard a few times gives the engine a chance to get up in the higher temps to burn off these deposits. Trust me this difference has nothing to do with the ecu changing the fuel map or ignition tuning. Think about it if I perform the same hard pull but only once the ecu should change the map to support my driving habit immediately. It literally takes a few hard runs like this for the engine note to change.

[TXT]

svard75 - I agree with you 100%. My comment may have sounded as though I didn't believe in it.

I have the 8 cylinder and I have gone through 2 episodes of the dreaded loud clicking noise due to hard acceleration while oil is low. First time, it went away after start up. 2nd time(August 2013) it didn't go away even after 3 days. I was getting desperate and before I decided to take desperate measures, I did the following:
Took a can a seafoam into gas tank while I had less than half a tank of gas. Car is still ticking. Obviously by this time I had filled oil up to proper level days earlier. I then proceeded to due the very thing that caused my ticking. Hard acceleration from dead stop. I don't know what happened but it went away right after that. This may not be directly related to rough idling due to carbon build up, but the italian tune up worked for me in that case.

I don't drive crazy, but I do it often to clear things out.

[szh]

The 'italian tune-up" is a way that Infiniti has recommended in a Service Bulletin to remove carbon deposits, by the way. See the TSBs in our Service Manuals location at NICO.

My approach is:

1. Try the high revving of the engine - you sometimes find that this is sufficient.
2. Try a BG-44K session (or two, but no more, in one oil change cycle) if the revving is not enough.

Both approaches have worked wonders the few times that I have encountered engine misbehavior (like stumbling, rattling on acceleration, etc.) in my M45.

Z

[szh]

To the OP and others, one of the issues with long idling has little to do with the engine - no real chance of damage there actually - but it may cause other kinds of damage elsewhere.

Usually, the engine does not heat up a lot, but the airflow into the compartment is minimally over the engine only. So, heat can build-up higher in other areas, since there is no air flow other than from the fan over the engine.

For example, your battery could get over-heated and die sooner. I have had this happen one time - was idling due to cold weather when waiting for my wife for something or the other and wanted to keep the car warm for my infant son and I (we were both asleep for at least 2 or 3 hours). We were outside in a parking area on a street so no chance of CO poisoning.

After that, when I turned the car off, the battery was completely dead although it had worked perfectly well when I stopped there. Had to get AAA to jump-start and they noted a battery bulge as well. And, then I had to change it out the next day when I got home and the car would not start at all in my garage.

Z

[myother45isalesbaer]

For the past year I've been idling my car A LOT while doing my audio set up and doing computer programming for my front end for my computer. While doing research on how to calculate gas burn during idling I found out that idling can damage your engine. I have noticed that the car has been driving a little rougher, noticeable to me, and don't really understand why, so for now ill attribute it to excessive idling since finding this out. How much is excessive? Just so I'm clear, up to 4 hours at a time.

So my question is, although extremely general, how do I go about repairing damage caused by excessive idling if nothing is standing out? What would you look to fix or change that could have been warn or damaged due to idling? What first? And tell me the rough cost because I'm not an engine guy. Thanks.

Whoa...that's a long idle time. But, and I don' know why its called an "Italian tune-up" but we used to do the same thing and called it blowing out the plugs. Some WOT used to blow the carbon build up out. We did this with our cars and bikes and it seemed to work. On todays cars I would fill up on premium gas, add some octane boost and a fuel injector cleaner. You could do FEW WOT's at a stand still, not too long, less than a minute and then take It out on the highway, even in first or second and do it again. It worked for me. Good luck.

[svard75]

It's referred to the Italian tune up because it is what Italian Ferrari drivers used to do with cars that used to be driven like an old lady to bring it back into spec.

[myother45isalesbaer]

It's referred to the Italian tune up because it is what Italian Ferrari drivers used to do with cars that used to be driven like an old lady to bring it back into spec.

Did not know that. Thanks for the info. Makes sense to me.

[steve_c]

Good responses in the previous postings regarding this issue.
During excessive idling, engine operating temps (water & oil) as well as engine oil pressure may not maximized. Rich fuel conditions wash down the cylinder bores, taking with it the oil needed to lube the piston rings. Unburned fuel merges with the oil in the crankcase (oil pan). Now you have compromized oil (thin oil from raw fuel contamination). Lower oil pressure & diluted oil work their way into & onto the various bearings, lobes, lifters, etc. causing them to wear prematurely.

The best defense (if excessive idling cannot be avoided) is frequent engine oil changes.

I agree with the other posters that todays engines are probably more resilient to the above for various reasons, but it still could be an issue. I would perform more frequent oil changes if excessive idling is the norm.

[myother45isalesbaer]

Good responses in the previous postings regarding this issue.
During excessive idling, engine operating temps (water & oil) as well as engine oil pressure may not maximized. Rich fuel conditions wash down the cylinder bores, taking with it the oil needed to lube the piston rings. Unburned fuel merges with the oil in the crankcase (oil pan). Now you have compromized oil (thin oil from raw fuel contamination). Lower oil pressure & diluted oil work their way into & onto the various bearings, lobes, lifters, etc. causing them to wear prematurely.

The best defense (if excessive idling cannot be avoided) is frequent engine oil changes.

I agree with the other posters that todays engines are probably more resilient to the above for various reasons, but it still could be an issue. I would perform more frequent oil changes if excessive idling is the norm.

I must agree. Excessive idle time is not good for any type of motor. Try it with a 2 cycle engine and you will see what excessive idle time will do. You then have to run them at WOT to get all the junk out of them before they can run at max power again. Our cars are the same just not as bad as a 2 cycle engines. In my OP 4 hours idle time is over the limits, unless you drive a cop car in which case they don't care or blow it out on the highway. I would recommend to the OP don't idle that long. IF you need heat buy a portable heater. Its cheaper than having to deal with all the issues other posters have made.