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Discussion Starter #1
yeah. When my engine is cold (as in 1 bar) with an outside temperature under 45 degrees it idles at a ludicrous speed. I put the car in drive and don't touch the gas pedal the car will get up to 18 mph. It even changes to second gear.

But once it warms up it doesn't do it anymore. I never had this problem in my 02 civic, so I was just wondering if this is normal or not. My thought i that because the engine is cold it keeps the rpm's higher thus causing the speed to go up.

weird...
 

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Discussion Starter #3
haha, i knew it wasn't normal. that would be frightening if that was normal.

it's weird that it only does it once. Usually by the time I stop and get going again the engine is warm enough and it won't do it again.

I know my dealer will pull some crap and pull the "We can't reproduce" card.

hmmmmmmm....
 

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That sounds pretty normal to me.

If the car will idle at around 7mph when the engine is fully warmed up, it makes sense. Before the engine is warmed up the idle rpms are triple (or more) the normal rpms, so the car will go faster...
 

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Its normal. The car's REVS are higher becuase the car needs to fully warm up. SOmetimes the car is jerky when you take off when cold becuase the car runs overly rich to heat up the catalist.
 

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Discussion Starter #7
That sounds pretty normal to me.

If the car will idle at around 7mph when the engine is fully warmed up, it makes sense. Before the engine is warmed up the idle rpms are triple (or more) the normal rpms, so the car will go faster...


that was my theory. maybe I just need to warm my engine up more. but I hate idling the car for 5 minutes because it wastes gas.

(there is not an emoticon to express how i feel.) :biggrin:
 

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^ Your barley burning any gas at all at idle. theres no load on the motor.
 

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Discussion Starter #10
^ Your barley burning any gas at all at idle. theres no load on the motor.
I always thought that it burned more gas than it was worth, but if it calms down the idle then it's worth it.

maybe I'll try warming it up longer after I fill up again and see how much my mileage is effected.


thanks for all the quick feedback everyone. :thumb:
 

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It dosnt waste hardley any gas at all guys. theres no load on the engine. Your also at 800 RPM. Its barley sipping fumes.
 

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i could smell gas today.... i was smoking my cig infront of the exhaust... after having started the car..... letting it warm up.

i was like...why does this place smell of gas station ?


weird
 

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Def. let the engine warm up when its cold. Would you rather waste $0.03 worth of gas or screw up your engine...not a tough decision in my book.
 

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idiling to warm up your car is not neccesary at all... just take it easy on acceleration and dont do highway speeds on your cold engine and you will be fine. Just take everything nice and slow. only takes about a mine for your engine to be fully warmed.
 

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When the engine is cold, the Intake Air Bypass Control Thermal Valve sends air to the injectors. (Bypassing the throttle.) It's regulated by engine coolant temperature. Once it's hot enough, it closes.

Because of the added air, the engine will require more fuel AND the idle will be higher. How much higher varies. Honda doesn't spec cold idle speed (only hot idle speed) as far as I can tell.

What RPM is your cold idle when you are in neutral? I don't have an R18, so if several of you report that, than you'll know what "typical" is. If you are outside of "typical" (or even high typical) consider having a mechanic take a quick look. (It means dropping your car off the night before so they can see your cold idle behavior.)


But if you *are* in the typical range, DO NOT "warm up" your car in the driveway. During cold idle you're burning well over a liter of fuel an hour for no good reason. (You get ZERO MPG!) Just drive, that's the best, most fuel efficient method of warming up your engine. The only exception is safety related - on some humid days you want just enough coolant temperature to be able to operate the defroster efficiently. But otherwise you are just burning over a liter of fuel an hour for no good reason.

(OK, the other exception is extreme cold, but a block heater and a grille block is the far better solution there.)

OH, the guy down in texas whose car smells like a gas station? That's not normal. The engine only operates open loop for a *VERY* short amount of time (seconds, not minutes). Closed loop is an efficient burn. It'll take a while for the cat to get up to efficient operating temperature, but on the R18 that happens very quickly as well. The cat will be working well long before the IABCTV closes.

-mr. bill
 
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