TT

Pin 1 - + side of temp sensor input
Pin 2 - AFM output (voltage from barn door wiper)
Pin 3 - 5V supply from DME to AFM for air flow readings
Pin 4 - Ground for everything

The MAF by itself should have 12V, Ground, and MAF Signal Out. Not sure how Autothority cables their setup, but one more wire for the fixed temp sensor input would be required. Make sure the MAF has a ground connection. Connect one leg of the air temp sensor to the wire that went to Pin 1 of the AFM connector and the other leg to ground wire of the MAF.

Andy

[quote]Pin 1 - + side of temp sensor input
Pin 2 - AFM output (voltage from barn door wiper)
Pin 3 - 5V supply from DME to AFM for air flow readings
Pin 4 - Ground for everything<hr></blockquote>

Sounds right, on the APE MAF, they are as follows:

Pin 1 - + side of rheostat (in my new case, temp sensor input)
Pin 2 - MAF output
Pin 3 - Unused
Pin 4 - Ground for everything
Separate 12V supply from Diagnostic plug.

Matt, I don't have a working digital camera right now, I'll see what I can do but don't hold your breath...

I think APE looked at as the MAF should be accounting for temperature and they could use this loop for a small amount of adjustment.

Matt Sheppard

[quote]I think APE looked at as the MAF should be accounting for temperature and they could use this loop for a small amount of adjustment. <hr></blockquote>

Well not if the DME system is making corrections based on this sensors input. Yes air temp would play a role in the flow signal being sent back, but the air temp sensor being sent as a static signal isnt letting the system work to it's fullest potential, so. . .

I can see the point if this were a track-only unit where you did a few runs, played w/ the rheostat and got it there, you should have no problems, but not for a driver that's started in 35 deg. F weather in the AM and driven through 95 deg. F temps later in the day. I think Lindsey is onto something w/ their design. Let's face it, we need all the help Bosch orig. offered, why leave the change on the table?

Is my "engineering" wrong on this?

Danno

Matt, you're right on. The type of air-temp correction that the MAF has built-in is only for achieving stoich. mixtures. It can take the place of additional altitude and air-temp computations that's normally required to arrive at a 14.7:1 mixture. But this is only under normal-operating conditions when the car's warmed up, and on a 70-degree day.

However, the MAF alone CANNOT trigger the DME to provide additional fuel above stoich. 14.7: 1 mixtures. There's some air-temp based enrichments written in the DME that can provide up to 16% fuel-enrichment on cold days. Without the air-temp sensor to trigger this enrichment, you'll just get the standard 14.7:1.

What you guys who've been twisting your ARC2 ***** are doing is basically going back to the carburetor days of a manual choke.

shaheed

[quote]Originally posted by Andy:
<strong>

Matt, I don't have a working digital camera right now, I'll see what I can do but don't hold your breath...

.</strong><hr></blockquote>

you could always come do mine and i'll take pictures for you

Andy

I have a better idea Shaheed. You could come by my place with the fancy camera, take some pictures, then you'd know how to do it yourself!
<img src="graemlins/roflmao.gif" border="0" alt="[hiha]" />

shaheed

[quote]Originally posted by Andy:
<strong>I have a better idea Shaheed. You could come by my place with the fancy camera, take some pictures, then you'd know how to do it yourself!
<img src="graemlins/roflmao.gif" border="0" alt="[hiha]" /> </strong><hr></blockquote>

depends on the weather this weekend, i may not want to drive the car without temp compensation....

IanM

Has anyone tried installing an aftermarket air temp sensor, rather than messing around with the factory one? I found this one on the MSD website. They're pretty cheap too, around $30.


This might be the way to go, drill a hole, weld a nut onto the MAF pipe after the air filter, and thread one of these things in. What do you guys think?

tecart

those of us with the maf kits need one of these if they work, please try it out and let us know if they fix cold start problems, im following you ian it seems but not on purpose