My brother's AV6 is having bad gas mileage at about 17MPG around town... He also has an APEXi AFC installed he got with the car...

I looked at the VTEC engagment, its set at:
L - H 3800
H - L 3500

The car has a CAI, computech exhaust, and nitrous (he never uses)... So basic bolt ons... He dosnt race it, just drives around town... My question is, could the low engagment of the VTEC be whats killing his gas? And if is, whats a reasonable setting for his setup? Like I said, he dosnt race, but he does appreciate the quickness of the car... Also, what is the stock RPM engagement point for his engine? Thanks in advance...

 

I thought 17mpg was in the average range for the AV6? Maybe not....
Has he messed with the fuel settings at all because that will throw off gas mileage. I would look at that

 

Im not sure, I told him its a V6, its gonna eat more gas than his old CRX... He said its unusually low... When I looked it up, the site I checked said it should be getting 20MPG city /28MPG HWY... We havnt messed with anything... I just happened to be messing with the AFC today when he mentioned it... We d/led the manual, and thats how I found out the VTEC engagment was so low...

 

Stock vtec engages at 3500. Take that thing out if its not tuned, its messing up the car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legendaryyaj &raquo;</TD></TR><TR><TD CLASS="quote">Stock vtec engages at 3500. Take that thing out if its not tuned, its messing up the car.</TD></TR></TABLE>

I would have to agree. I would also go as far as saying that it is pointless to have a vafc with as few mods as he has done. There is no need for it especially if he is not adjusting anything.

 

have the vafc dyno tuned, it's probably dumping/wasting too much fuel for no purpose.

might as well get a fuel pressure regulator instead of vafc if he's not gonna tune it.


those 98-02 v6 can go at least 300 with a full tank of 87

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iam7head &raquo;</TD></TR><TR><TD CLASS="quote">those 98-02 v6 can go at least 300 with a full tank of 87 </TD></TR></TABLE>

I go more than 300 everytime.

 

Thats the thing, I dont know if it is tuned or not... I assumed the guy who bought the car had it done... Since the rest of the car was done correctly, Im sure he had someone tune it... And I dont think we have a local dyno tuner in are area either... And since VTEC is 3500, and its set to 3500 that cant be it... What fuel setting should I set it at? Or should I even mess with it at all?

 

Just unplug the VAFC and leave it as is.

 

So in other words, u have to have a dyno to tune these things? I am doing a VTEC swap into my CRX and was thinking about getting one to activate VTEC, rather than having to go OBD1... But if u have to have a dyno to tune it, screw that! Thanks for the help tho guys!