MAFT Pro in AFC Mode. Do or don't...?

[CajunKenny]

I'm considering installing my maft pro and running it in AFC mode until I can get some welding done for the speed density sensor.

Should I do it or just wait...what's your opinion?

Thanks everyone!

 

[GrimJack]

I don't see why not... it certainly shouldn't cause any harm, and it'll spread the installation woe out over a longer period.

 

[CajunKenny]

Good point. It seems that most folks run it in speed density. I have the harness for it; but, won't get to install that part of it for a little while.

I didn't know if AFC mode was more of a headach than speed density mode. Just putting the feelers out there hoping some AFC mode guys could chime in...

 

[dumbo]

2 quick q's

Whats AFC mode?
What welding do you need for the MAP sensor?

EDIT: OHHH!, do you mean welding for the temp sensor?

 

[CajunKenny]

Yep for the temp sensor.

AFC mode = non-speed density. He he...

I'm not there yet; but, I think it's just controlling afr's.

 

[sneakypete]

in AFC mode you keep the afm and basically use the maftpro like its a SAFC

 

[dumbo]

Oh K. Why not just pick where you want the AIT sensor pull that pipe and bring it to a shop somewhere close to you? I'm sure if you ask nice someone would do it for free if you had the bung. I put mine in the front right kinda near the NA PS resivoir.(ETS pipes). Had to lengthen all the wires for the sensors. Good luck, trust me its fun

 

[CajunKenny]

I am changing intercoolers and IC piping. I’m not sure when I can coordinate with my welder friend to get that done so I was just going to put my 550’s and Maft in and run it AFC until we can get everything welded up.

 

[GrimJack]

That'll work. Remember to put the temp sensor away from the exhaust / turbo... I put mine between the valve covers initially, and it heat soaks something awful there.

So I moved it to the passenger side front, where the IC pipes go through the fenderwall.

 

[CajunKenny]

Wow! Thanks for that! That's exactly where I was going to mount it was between the valve covers.

Did you have to use any cable extensions?

 

[GrimJack]

Nope, it reaches there just fine.

 

[dumbo]

Nope, it reaches there just fine.

Crazy! I had to extend mine but it's only 2 wires, not a real hassel. I also had to extend the wires for my MAP sensor too(3wires), mounted below the brake/clutch MC's.

 

[GrimJack]

Where did you mount your MAFT Pro, and how did you route the wires? Mine is below the stereo, and I put the wires through the Engine harness plug in the firewall.

 

[dumbo]

Where did you mount your MAFT Pro, and how did you route the wires? Mine is below the stereo, and I put the wires through the Engine harness plug in the firewall.

Exactly the same, it's like they designed the maft pro to fit right in there, tucks away so perfectly eh?

Maybe our harnesses were different, I'm sure theres no adverse effects of having longer wires.

 

[CajunKenny]

Ok. I'm going to shoot for installing my 550's and the maft this weekend. I'll be running in AFC mode for now.

I want to get feeback from folks as to what they're idle afr is AND what is ideal.

My idle afr currently fluctuates between 14.6-15.2 after driving around for a bit.

While cruising at a steady 40 mph and ~2k rpm, it's exactly the same. Between 14.6-15.2. Is this the norm?

I don't want to install the maft on an existing problem.

What may also be noteworthy about my car is that it is currently pulling 15-17 inhg. Should this be addressed prior to the maft and 550's install? I already checked for vac leaks and there are none.

No other problems noted by the way...

 

[sneakypete]

Ok. I'm going to shoot for installing my 550's and the maft this weekend. I'll be running in AFC mode for now.

I want to get feeback from folks as to what they're idle afr is AND what is ideal.

My idle afr currently fluctuates between 14.6-15.2 after driving around for a bit.

While cruising at a steady 40 mph and ~2k rpm, it's exactly the same. Between 14.6-15.2. Is this the norm?

I don't want to install the maft on an existing problem.

What may also be noteworthy about my car is that it is currently pulling 15-17 inhg. Should this be addressed prior to the maft and 550's install? I already checked for vac leaks and there are none.

No other problems noted by the way...

im running 550s and a walboro and my idle afr is 14.7 +/- .2
at cruise with minimal load its around 14.5 afr (for fuel efficiency). some people go leaner but im comfortable where im at.
is your vacuum reading at idle or during cruise? im assuming idle. the norm is around 20 in hg. search for vacuum readings and you will find a good link that will help you diagnose your issue if there is one... providing you definitely dont have a vacuum leak.

-pete

 

[CajunKenny]

Thanks for the afr's.

I disconnected my pcv and isc hoses, plugged them, and the car died immediately. That's how I checked for vac leaks.

I followed jdub's suggestions and we left off with me needing to do a compression and leak down test. I'll try to get that done before the weekend.

 

[GrimJack]

My AFR at idle varies a lot more than that... goes from about 13.9 to 15.0. It's *usually* right around 14.7, but it does waver about quite a bit.

 

[dumbo]

Yah my idle bounces around 14-15, and about 16 lean cruise thats fuel economy. My engine also pulls 25in/hg, maybe that has to do with GE pistons, and valve lash in spec.

I would say your AFR's are right on the button so I wouldn't worry about that. But the vacum seems a little low.

 

[CajunKenny]

So, what tuning process has worked for you guys? Set the desired boost level then get the AFR's where you want them or the other way around?