Idle

[SVOboy]

I imagine I will have to start doing this,

Also, do you think we auto people coudl benefit from loosening up our throttle cables so that the car doesn't feel the need to always propel itself forward while in drive so much?

[krousdb]

Originally Posted by SVOboy

I imagine I will have to start doing this,

Also, do you think we auto people coudl benefit from loosening up our throttle cables so that the car doesn't feel the need to always propel itself forward while in drive so much?

I thought that the "crawl" was a function of idle speed and torque converter stall speed. I think the solution would be to lower the idle, which would create less load on the engine due to the torque converter. Still better would be to shift into neutral. Best of all is to kill the engine all together.

[SVOboy]

I didn't know if the crawl was the cable or what, thanks for the enlightenment, I know much less than I should about automatic transmissions.

[Matt Timion]

Originally Posted by SVOboy

I didn't know if the crawl was the cable or what, thanks for the enlightenment, I know much less than I should about automatic transmissions.

I'm still pretty convinced that auto transmissions are witchcraft.

[philmcneal]

Best of all is to kill the engine all together.

At every red light ;O?

[krousdb]

Originally Posted by philmcneal

At every red light ;O?

At every long one.

[philmcneal]

At every long one.

What's your minimum 30 seconds of ICE OFF time? That should be the savings equivilant of an extra mile you can go as opposed if that 30 seconds was ON and actually GOING somewhere instead of WAITING for a light to turn GREEN.

[Compaq888]

Seems to help, and so does the new intake hose. I got 27.6mpg 70-80% on the streets. This switching to N thing mainly works on big intersections since that's where the most idling is. When I put it N the rpms go up by 200-250rpm and go down to the same rpm as it was If I was idling in D. I'm now going to do this. Hopefully I'll break 28mpg 70% city driving next time.

[Sludgy]

With my diesel, the RPMs stay the same regardless of whether it's in gear or neutral. The engine definitiely uses less fuel in neutral and it stays at the same RPM as in gear. There must be some feedback control to keep idle RPMs constant.

Your idle RPMs go up when you put the car in neutral? Do all gas engines do this? Wouldn't the higher RPMs use more gas?

Do you have a Scangage to tell what happens?

[Compaq888]

no, it goes up for a second then comes down to the same rpm as it was in D. Here is how i think it works...I think Bunger will agree with me.

I stop, put in N. Rpms go up because there is less load for the same fuel input then computer realizes there is no load and lowers rpm in neutral to the same rpm as it was in Drive. When I put the car back in Drive the rpms dip to 500rpm because of the Torque converter and the engine adds more fuel to keep it at 650rpm. Both N and D are 650rpm. But the difference is N has no load so the engine uses less fuel to idle. In D the engine idles in same rpm but uses more fuel because the Torque converter is now working.

I don't have a Scangauge, I use mpg trips to see the changes in my gas mileage and this website to see what works and what doesn't work. I think so far my street mpg is 23-24mpg. While my freeway should be around 35mpg. Every month I do something new to the car which improves my mpg.