MAF

Snorkus, filters, throttle bodies and intake manifolds.

Moderators: Helpinators, Moderators

Post Reply
irishsetter
First Gear
Posts: 238
Joined: Wed Jul 07, 2004 12:23 am
Location: Jacksonville fl

MAF

Post by irishsetter »

Ok what is the difference between a MAF and a MAP. Which one is right after the intake box. If I am not getting 11 volts output from it is it done or can I clean it or rebiuld it?
wiscon_mark
Fourth Gear
Posts: 1141
Joined: Tue Sep 20, 2005 4:04 am
Location: Stevens Point, WI

Post by wiscon_mark »

MAF is right after the filter box.

You can clean it, but be VERY careful, as it is delicate.
[url=http://www.sl-i.net/FORUM/viewtopic.php?t=486]1995 Legacy Outback 5MT[/url]
185,000 miles
www.sl-i.net (for all Legacys!)
Subaru_Nation555
Third Gear
Posts: 819
Joined: Wed Oct 27, 2004 6:54 am
Location: Arlington, VA

Post by Subaru_Nation555 »

MAF-mass air flow sensor-measures incoming air
MAP-manifold absolute pressure sensor-measures vacuum (engine load)

I used brake clearner to clean my MAF when I was trying to troubleshoot something. Like wiscon_mark said its delicate.
BAC5.2
Moderator
Moderator
Posts: 9026
Joined: Thu Jan 29, 2004 8:47 pm
Location: Maryland www.andrewtechautomotive.com
Contact:

Post by BAC5.2 »

MAP sensors don't only measure vacuum. They can measure anything having to do with pressure (or lack thereof) in the manifold.

That's why you can see Skylines or WRX's or whatever with open turbo inlets and no MAF's. They are fueling based on MAP signal compared to a few different things, essentially calculating the Volumetric efficiency of the engine from various sensors and compared to atmopsheric, and it fuels from that.... from what I understand anyways.

It's pretty difficult to set up and properly tune a MAP based fueling system, but it's possible and can be nice for pipe routing. It's not as percise though, so you do take your chances.
2009 Outback 2.5XT. 5MT. Satin White Pearl.
2009 Impreza 2.5i Premium. Blue.

[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
Psychoreo
Second Gear
Posts: 360
Joined: Tue Jan 18, 2005 11:07 pm
Location: Enfield, CT

Post by Psychoreo »

speaking of MAF and MAP sensors, are the wires between the two harnesses the same? the plug is the same, just do they go to the same places?
stupid electrical work...
BAC5.2
Moderator
Moderator
Posts: 9026
Joined: Thu Jan 29, 2004 8:47 pm
Location: Maryland www.andrewtechautomotive.com
Contact:

Post by BAC5.2 »

Lots of plugs are the same. That doesn't mean they go to the same place.

The scan port plug is the same as a radio plug, and the plug for the tail light.

But no, they don't go to the same place. They both go to the ECU, but not to the same pins.
2009 Outback 2.5XT. 5MT. Satin White Pearl.
2009 Impreza 2.5i Premium. Blue.

[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
Psychoreo
Second Gear
Posts: 360
Joined: Tue Jan 18, 2005 11:07 pm
Location: Enfield, CT

Post by Psychoreo »

yea, thats what i gathered from the swap wireing thread. not to hijack this thread but , nevermind that would be hijacking i'll ask in another section.
stupid electrical work...
Puprap
In Neutral
Posts: 1
Joined: Wed Aug 02, 2006 7:23 pm
Location: USA
Contact:

Post by Puprap »

Achtung!!
[url=http://vhf.gaka.info/propagation.html]Vhf Propagation[/url]
Lowjack
In Neutral
Posts: 10
Joined: Mon Aug 14, 2006 8:47 am
Location: Salem, Oregon
Contact:

Post by Lowjack »

Subaru_Nation555 wrote:I used brake clearner to clean my MAF when I was trying to troubleshoot something. Like wiscon_mark said its delicate.
Try to stay away from brake clean and carb cleaners. They'll actually damage electronic components. Try to get some electronics cleaner from Radio Shack. Much better/safer/smarter
1990 Legacy Sedan

I've got a lovely bunch of coconuts....
Post Reply