New Accessory Pulley = Better MPG? - Page 3 - Fuel Economy, Hypermiling, EcoModding News and Forum

Tygen1 · 09-04-2009, 04:51 PM

Remember that I have the Powder Underdrive Pulley. 40% UDP ought to help this idle gph a bit. I'm interested in what Zach's idle GPH is because he deleted the P/S and A/C. I believe that this has caused about a +1mpg jump because the idle gph is lower and I do a lot of coasting with the engine on....atx.

Tygen1 · 09-08-2009, 01:36 PM

Hmmmmmm..... Found an unpluged vacuum line after the MAF. Plugged it back in and things are not the same....Could this have leaned things out a bit??? Still waiting for the ECU to adjust to this new enviroment. This could be the cause of the increase in MPG, now I'm really curious!

Christ · 09-08-2009, 04:52 PM

Wow... never heard of anyone being excited about a vacuum leak. Waiting for the results... this shouldn't take long - you have a SGII, correct?

Tygen1 · 09-08-2009, 06:55 PM

Yes, SG2. However it takes the ECU about 60-80 miles to sort things out when a change this big happens. After plugging it in the idle gph shot up to 0.20+ but has settled down to around 0.16 which is about where it was before.... Maybe the vacuum leak was enough that the ECU couldn't fully compensate and therefore it was running a bit lean??? but that doesn't make sence, I don't know....I guess I need to do some testing. My SG has the AFR and O2 voltage programed in as Xgauges, but they often display crazy numbers....

i_am_socket · 09-09-2009, 04:45 PM

Stopped at idle, fully warmed up, in Neutral, on a 70F day it hovers around .30-.33. Putting it in gear brings it up to ~.45 and A/C on and pumping will bring it up to ~.55. I'm still working on how to disable the DRLs so I can see if there's any improvement there. Oh, to have time and any kind of mechanical skill....

yanlapanic: the front of my car doesn't actually look like that (yet. but one day when I have time, money, and materials...)

Christ · 09-10-2009, 03:29 PM

Quote:

Originally Posted by i_am_socket

Stopped at idle, fully warmed up, in Neutral, on a 70F day it hovers around .30-.33. Putting it in gear brings it up to ~.45 and A/C on and pumping will bring it up to ~.55. I'm still working on how to disable the DRLs so I can see if there's any improvement there. Oh, to have time and any kind of mechanical skill....

yanlapanic: the front of my car doesn't actually look like that (yet. but one day when I have time, money, and materials...)

If you want to check your idle consumption w/ the DRL's off, you should be able to pull up your e-brake one click, then check it.