[AJ_Schreiber]

Doing a road trip next week and plan to sleep in the back of my 2000 DGC with the 3.3. I plan to have the car running to keep the AC on and keep me comfortable but I was wondering if anyone knows or knows a way to find out the GPH at idle so I know roughly how much fuel I'll burn. Thanks for any input

 

[ImperialCrown]

I suppose you could monitor the fuel gauge with the engine idling for an hour and calculate it from there. The radiator fan will be on most all of the time as air won't be flowing through the radiator and condenser. The cooling system must be in good shape as overheating could occur if it is not.
I would be very concerned with Carbon Monoxide entering the vehicle. Buy a loud CO detector for the van if you are going to do this. Even with windows closed, the van is not airtight.
Watch for the local authorities as they would consider a running, out-of-state vehicle suspicious and you may be searched and ticketed for vagrancy.
Sleeping inside a running vehicle is not recommended. I would try to find a good cheap motel rate in the area instead.

 

[chuzz]

I gotta agree with IC on that one, AJ. It simply isn't worth the risk. A blown head gasket can be repaired, but you CAN'T be replaced. Don't do it, man.

 

[Stratuscaster]

I'll third that suggestion. I'd sooner carry a small gas generator and use a portable AC or fan than just let the van idle overnight.

 

[Bob Lincoln]

Way too dangerous. And in many states it's illegal to leave a vehicle running unattended (that being defined as no one behind the wheel). Besides the CO hazard, someone can break the glass and hijack it, mug you, etc. The catalytic converter can overheat and cause a vehicle fire, and you could be injured or die. Why are you contemplating this vs camping or a motel?

To answer the question, the EVIC in my Daytona with 4 injectors running indicates that it might burn roughly a gallon per hour, based on running it for 5 minutes and extrapolating. That's a very rough estimate, it could be double for your vehicle.

 

[Doug D]

+4! Idling for hours is NOT RECOMENDED. I understand wanting to be comfortable, but you're better off finding a cheap hotel/motel or just camping under the stars than idling an engine to get AC and be comfy........

Even running a gas generator requires some monitoring. I would not recommend running a gas generator while sleeping - even if it is outside.

That said, a V6 would probably burn about half gallon per hour at idle. V8 closer to a gallon.

 

[dana44]

Start weighing the cost of gas while idling and the cost of possible damage for idling that much against the cost of a hotel and a cheap hotel starts looking pretty comfortable and cheap.

 

[Dave Z]

I think our 300C came out as 0.3 gallons/hour while idling, according to a meter, though I agree with everyone else here, and I don't trust that figure anyway. Gas mileage drops too quickly at red lights.

 

[AJ_Schreiber]

The entire cooling system has less then 10k miles on them and I upgraded to the HD radiator. I rigged an alarm that goes off if the CEL, overheat, or oil pressure light comes on. I have found no evidence that prolonged idle severely damages your vehicle, sure it puts more wear and tear on it, but whats the difference between sitting there and continuous stop and go traffic? again, with the alarm Im not worried about any catastrophic mechanical issues. I didnt think about CO though, thanks for letting me know. I'd of course only sleep at well lit truck stops. But if you guy say no then I trust your judgement

 

[Dave Z]

You could take a little tent-trailer along and I guess it's guaranteed free of bedbugs.

What I'd probably do, depending on the weather, is get the car good and cold at bedtime, then shut it off, crack the windows, and hope for the best. With the doors locked, though that's not a major impediment to the nastier thieves.

 

[Doug D]

The entire cooling system has less then 10k miles on them and I upgraded to the HD radiator. I rigged an alarm that goes off if the CEL, overheat, or oil pressure light comes on. I have found no evidence that prolonged idle severely damages your vehicle, sure it puts more wear and tear on it, but whats the difference between sitting there and continuous stop and go traffic? again, with the alarm Im not worried about any catastrophic mechanical issues. I didnt think about CO though, thanks for letting me know. I'd of course only sleep at well lit truck stops. But if you guy say no then I trust your judgement

The biggest risk is the CO concern, not so much the engine suffering damage.

Don't know if doing this at a truck stop is a good thing or not. They can be quite busy when you'll probably be trying to rest.

I'd think a rest area would be better if you are west of the Mississippi. On our last trip out west to Denver, I noticed there wasn't a time limit when you stopped at a rest area at most rest stops west of the Mighty Mississippi. And many times you could tell some travelers had been camped there for a while. I know on the east coast most rest areas have a two hour time limit. Of course, you'd still have the security concerns regardless if you're at a truck stop or rest area.

Even when I have stopped at a rest area to "rest" I could never really rest. Just too many people coming and going.

Once on a trip to Florida we stopped at the rest area just south of the NC/VA border on I-95, Even though it was 3 or 4 AM, the rest stop was nearly full, maybe 5 parking spots open when I rolled in.......Couldn't believe how many people were traveling at night,

 

[Stratuscaster]

What you lack when you aren't moving is that flow of air through the radiator. Yes, the fans would be running, but sometimes that may not be enough - especially on an older vehicle.

I suppose you can "do like the RVers sometimes do" and camp in the Wal-Mart parking lots.

 

[John Wood]

I've often exceeded the 2 hour limit at Interstate rest areas and have never been bothered. When I drove from Florida to Vermont in late June, I hit the PA welcome station on I81 at 8:30 PM. I slept in the back of the van (no rear sets) until midnight and then continued up to Scranton where I slept until about 5:30 AM. I found that at about 9:00 PM, it had cooled enough to be tolerable.

In 2012, I made a similar trip and temps were in the low 100's on I95 in VA. I headed over to the Shennadoah NP and found it to be a little cooler (upper 80's) but still too warm to sleep in the van. I got a campsite that was grassy and just put a tarp and sleeping bag out (no tent). I put a little insect repellant on and slept for an hour until the storms hit. The storms cooled the air so I crawled into the dry van and slept through the stormy night. By morning I was reaching for extra blankets to stay warm.

I never had to run the van or turn the AC on. Usually after it gets dark it cools enough to be tolerable. If you get rain it also usually cools off pretty well.

In any case, have a good trip and be safe!

 

[AJ_Schreiber]

thanks for the input from everyone, Im glad this started a healthy and interesting conversation. I probably will drive until it's cool enough to sleep and wont idle all night. I was just curious as to everyone's input. As to the Cat overheating I doubt this is an issue considering how extremely tight modern fuel injection engines monitor fuel air ratios. Yes you lack air moving over it to cool it, but I'm more then certain Chrysler engineers made sure that it wouldnt become a fire hazard or we'd have lawsuits galore on it considering how popular the 3rd gen vans were/are.
Also, even those fancy gentleman's hotels where you can pay by the hour are too much. I'm a college student living off of minimum wage, so all I have a budget for is all the gas I need and about $20 extra for food and whatever else. So this is why I plan to just fold the 3rd row flat and sleep in my van.

 

[ptschett]

For both the engine & catalyst, I wouldn't be worried about overheating; I'd be worried that critical parts would become too cold from an extremely-extended, overnight idle.

In the case of the engine my concern would be low cylinder wall temperatures and low oil temperatures, leading to a risk of oil degradation from unburnt fuel and from combustion-produced water vapor having an opportunity to condense in the crankcase ventilation system.

WRT the catalytic converter I'd be worried that it would become too cold during the idle period, dropping below its activation temperature, and then overheat when the vehicle is driven away due to accumulated particulate matter (insufficently-burnt fuel, etc.)

The difference between a prolonged idle, and stop-and-go traffic is the "go" part of the traffic situation. The engine periodically gets placed under load, helping to keep the components and fluids at their operating temperatures.

 

[gusc]

I'm so afraid of CO I won't even run my RV generator at night.

We just cool it down while we're awake and shut it off to sleep.

Once the sun is down a metal vehicle cools off very quickly.

 

[Stratuscaster]

On the subject - where are you going on your trip, AJ?

 

[AJ_Schreiber]

Starting in North Utah, Picking up a friend in Boise then headed to Phoenix.

 

[AJ_Schreiber]

For both the engine & catalyst, I wouldn't be worried about overheating; I'd be worried that critical parts would become too cold from an extremely-extended, overnight idle.

In the case of the engine my concern would be low cylinder wall temperatures and low oil temperatures, leading to a risk of oil degradation from unburnt fuel and from combustion-produced water vapor having an opportunity to condense in the crankcase ventilation system.

WRT the catalytic converter I'd be worried that it would become too cold during the idle period, dropping below its activation temperature, and then overheat when the vehicle is driven away due to accumulated particulate matter (insufficently-burnt fuel, etc.)

The difference between a prolonged idle, and stop-and-go traffic is the "go" part of the traffic situation. The engine periodically gets placed under load, helping to keep the components and fluids at their operating temperatures.

I dont think unburnt fuel is an issue in MPI fuel injection engines. Provided everything's in working order you will all ways get equal parts air and equal parts fuel, regardless of engine speed. I'd agree with you if the engine were carburated but again, with FI, I dont see how thats an issue. I do see how left over particulates can accumulate at idle since there is less pressure to force nastiness through. But even here I'm sure the engineers thought about that and designed that into the exhaust system. So even then the impact would be minimal at least.
As with physical temperature while it will be lower at idle I again fail to see how that's an issue. Provided the thermostat is working the engine temp will always be kept within its operating range. Now I wouldnt wake up and immediatly race the 24 hour Le Mans, but for normal run of the mill driving it should be just fine. Again on the basis of that's what it's designed to do.

 

[Bob Lincoln]

I don't see a specific warning in my wife's 2012 owner's manual, but in earlier EFI car manuals, there was a warning not to idle more than 20 minutes, because the catcon could overheat without airflow over it. Nevertheless, the CO risk is the biggest issue, and personal safety would be next. Is the price of a Motel 6 or Super 8 for the night out of your range?