What's that thing on my ECM

92TyLA

92TyLA

New member
Re: What's that thing on my ECM

is it this box your talking about? If not/yes what the hell is this box for?
I was installing the Velosyty chip when I came across it
40dd35dd.jpg

70316cb7.jpg

dc8cb11f.jpg

e4cc6a3d.jpg

cb7d1f32.jpg
 
TNPhoon

TNPhoon

1of28
Re: What's that thing on my ECM

^ DRAC.
Just unplug it and throw the box away. You don't need that sheet. It's just the govamen's way of tracking you. :)
 
alwayscode390

alwayscode390

pppssssshhhhhtttttttttttt
Re: What's that thing on my ECM

Lots of guys run different diameter wheel/tire combos than stock ... how is that not messing up our DRAC? ---
 
RealFastV6

RealFastV6

@jb_and_his_coffee
Re: What's that thing on my ECM

alwayscode390 said:
Lots of guys run different diameter wheel/tire combos than stock ... how is that not messing up our DRAC? ---
Click to expand...

If you go down to lets say a 25.5" diameter tire, your speedo is going to show a faster speed than you're actually going (by about 2%). So when your speedo says 50, you're really going 49.

So yeah... it is messing it up... but unless it's a drastic change you won't notice it.
 
alwayscode390

alwayscode390

pppssssshhhhhtttttttttttt
Re: What's that thing on my ECM

When you get a tune/ chip installed ... can they adjust for differences in tire sizes?

I know they can on the OBD2 setups, not sure about the OBD1 stuff ---
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: What's that thing on my ECM

DaveP said:
You didn't specify what the original tire size was, so I can't double-check your math. But I have another observation. You say 2% is not a drastic change, and you won't notice it, which on the speedo is probably true enough. But this 2% also affects the odometer. Which is often used to compute fuel mileage. If your computed mileage is 20 MPG, Corrected by 2% you really got 19.6 MPG. May still be only 2% but the difference between 19.6 and 20.0 is significant to some people.

Remember how Honda got caught a few years ago with odometers that were reading as much as 10% high as-delivered? These 10%-inflated economy figures were probably reflected on the window sticker declarations, too. If you computed your Accord was getting 32MPG, and it really was actually covering 28.8, that';s a big difference. I don't recall THAT coming up in the news stories. It was mostly regarding running out of warranty 10% early.
Click to expand...

Probably affects warranty as well - if your engine mileage expires 10% earlier than promised, that's a big difference on a distribution curve.

Were they also under reading by 10%?
 
RealFastV6

RealFastV6

@jb_and_his_coffee
Re: What's that thing on my ECM

DaveP said:
You didn't specify what the original tire size was, so I can't double-check your math. But I have another observation. You say 2% is not a drastic change, and you won't notice it, which on the speedo is probably true enough. But this 2% also affects the odometer. Which is often used to compute fuel mileage. If your computed mileage is 20 MPG, Corrected by 2% you really got 19.6 MPG. May still be only 2% but the difference between 19.6 and 20.0 is significant to some people.
Click to expand...

Our tires are 26" tall from the factory, no? And yes, good point, also affects the odometer which would gain mileage ~2% faster than it really is in my example if you change the tire height without re-calibrating.

No need to check my math though, I didn't actually do any. It's all estimation. There's other folks on the forum who will quote lots of exact numbers if you're into that sort of thing. ;)
 
You must log in or register to reply here.
Top