How's your idle? (Just some idle blabbing)

[euromodder]

Typically 0.4 kg/h of low caloric CNG with a warm engine.

With AC on, double that.

[euromodder]

Originally Posted by HypermilerAX

I ran the engine for a minute or so in order to expel all the air. I waited for the engine to cool down completely. I noted the value every 10 seconds the first 10 minutes and then 30 seconds until 15 minutes.

I'm really surprised at how quickly the fuel consumption drops off - only the first minute is really the worst.

[arcosine]

.2 gal/hr after a 6 mile warm up, sc1 1.9L, gasoline. I try again when it's completely warmed up.

[arcosine]

.175 gal/hr engine warned up 20 miles, inlet air temp 130F, 700 RPM, I could lower the idle 100 rpm.

[digital rules]

Originally Posted by serialk11r

According to Torque and my Ebay OBDII scanner, 0.18 gph fully warmed up coolant at 680rpm idle for a pre 2003 Toyota 1ZZ-FE (1794cc)

Thanks, I was wondering what the norm was for the 1.8 liter Toyota engine. Scangauge bounces between .16 -.17 & Ultragauge .14 -.15 on my '05 1ZZ-FE.

Does your idle gradually drop to a low point & then exhibit a slight roughness? I always assumed the mixture was intentionally leaned out by the computer to improve idle FE. I recently replaced my intake manifold gasket & idle quality/ low end torque have noticeably improved but still not a silky smooth idle like a Honda 4 banger. MPG seems better too-425 miles & still a little over 1/4 tank left.

[NoD~]

My Neon started out as a big pig. It would start at .45 gph until warmed up, then go between .30-.33. I then cleaned out the AIC valve, which by cleaning, I mean I broke it! After putting it back in, it lowered the idle quite a bit to the point that it has a hard time keeping idle on its own from a cold start... but it would sit around .28-.30! Even still, compared to most modern engines, seems to be more than necessary. Though, I just don't even bother to let it idle just about anywhere anyways (EOC P&G EVERYWHERE!).

As for warmups, my car has had odd cooling issues from the start. When I first rebuilt the engine, silly me put the headgasket on upside-down and it allowed oil to get into the coolant. Since then, I've been struggling to get all the oil out (though nearly 2 years and many cleanout and part changes later, it's far better than it was). In the early life of this engine, it would get up to 220*F pretty easily. Fast forward to now, after extensive grill blocking and a smaller radiator, I struggle to ever see a full warm up! Only on constant steep hills do I ever get into the 195* territory... otherwise, it likes to sit around 180*. This is through 3 different thermostats now! I can only figure that the constant pulse and glide w/ engine off coasting is just too efficient? lol.

[serialk11r]

Originally Posted by digital rules

Thanks, I was wondering what the norm was for the 1.8 liter Toyota engine. Scangauge bounces between .16 -.17 & Ultragauge .14 -.15 on my '05 1ZZ-FE.

Does your idle gradually drop to a low point & then exhibit a slight roughness? I always assumed the mixture was intentionally leaned out by the computer to improve idle FE. I recently replaced my intake manifold gasket & idle quality/ low end torque have noticeably improved but still not a silky smooth idle like a Honda 4 banger. MPG seems better too-425 miles & still a little over 1/4 tank left.

Yea it does, the mixture is most certainly not being leaned out. The 1ZZ ECU runs rich if stumbling below idle speed, stoichiometric all conditions from idle up to ~4500rpm or so, and then open loop from there on at high throttle position.

The idle isn't as good as a Honda because the cams are single profile. The 2ZZ has a better idle than the 1ZZ, 7.2mm lift vs 9.4/8.6 intake/exhaust I think explains it. I would love to get a 2ZZ + C60 combo, raise the compression, custom grind the low cam for increased duration and fuel economy, but no money

[tvbd56]

My 1998 Honda Civic EX 4cyl 1.6L would be 0.2-0.22gph warm at idle, in neutral, e-brake on.

My 2005 Toyota Tacoma V6 4.0L will be ~0.35gph warm at idle

My 1990 Honda CRX HF...... I have no clue because it's OBD0 I'm guessing it's less than my old civic though.

[coquicr]

VW fox 2005, 1.6L: 740ml/h (0.19gph) @730rpm, no loads, parked
VW Crossfox 2012, 1.6L: 720ml/h (0.19gph)@710rpm, no loads, parked (just 15000km rolled)


This is what troubles me:

Chrysler sebring 98' 2.5L, 1.3L/h (0.35gph)@ 750rpm, no loads, parked, auto in neutral
....
Chrysler sebring 98' 2.5L, 2L/h (0.54gph) @ 1200 rpm, no loads, auto in neutral, rolling downhill @5mph Aprox.

Why does consumption goes so high when rolling? why does it need to raise rpm?

[topcat]

RPM and consumption also increase when rolling in my 1zz-fe Celica, I suspect in order to keep the brake boost and power steering topped up. When stationary at idle, just turning the steering wheel a little increases the rpm a little.