Need help with Computer and Mass air

[xpkpremier]

I am hearing different story's about using a 5 speed computer on a auto harness. Is it true, it wont work..........If not I will have a A9S for sale or trade to a A9L. All this Mass air flow junk is driving me nuts.....And is the Ford Motorsport Mass Air Conversion, plug and play.This is what it says "It is used on 86-88 mustang 5.0 to change your speed density to mass air by simply plugging this between your computer and existing harness. This is the easiest and fast way to change over". What about the VSS and the fuel pump?

Will this work or do I still need to run the other wires.......

[Ourobos]

A9S is a 5-speed computer.. As is the A9L.. The problem with the harness is mainly the O2 harness. Whatever O2 harness you have, you MUST use that same type of computer. The harnesses are wired differently.. Now if you are planning on running a mass air ECU with an automatic car, you will want the automatic computer, as they are more 'streetable' with gear changes, neutal, etc. You would want an A9P.

[grabbergreen84]

What about the VSS and the fuel pump?

The VSS, you can get from a junkyard (along with its connector and as much wire as possible). Might want to research the part numbers though, there maybe be differences in them, across the product line... Then you just need a good schematic to follow, to ensure wiring it correctly.

I would imagine that that Ford kit probably works the fuel pump, BUT, the later Fox MAF computers(if not all of them) use a pin to monitor power from/to the secondary circuit(fuel pump side) of the fuel pump relay. If this circuit is left out, you'll get a "Fuel Pump Secondary Circuit" code.

[xpkpremier]

A9S is a 5-speed computer.. As is the A9L.. The problem with the harness is mainly the O2 harness. Whatever O2 harness you have, you MUST use that same type of computer. The harnesses are wired differently.. Now if you are planning on running a mass air ECU with an automatic car, you will want the automatic computer, as they are more 'streetable' with gear changes, neutal, etc. You would want an A9P.

I mixed my puters up I meant to say was A9P, The car is an auto, but will be a 5 speed. so I need to get a auto puter. Or can I switch my 85 O2 harness over and get away with that??????The 85 is a 5 speed car.....To make this easy, just tell me what I need and I will buy it, This is what I have a 86 auto that will be a 5 speed and I want to use mass air flow....So what do I need besides the pigtail. I have everything for the 5 speed swap, just need mass air, the right way and not have to guess....

[Ourobos]

You can run any ECU, as long as the o2 wiring is matched up, so run the A9S and get a manual o2 harness. You'll need the pigtail and a mass air meter and tubing also.

[xpkpremier]

You can run any ECU, as long as the o2 wiring is matched up, so run the A9S and get a manual o2 harness. You'll need the pigtail and a mass air meter and tubing also.

Okay, will I have to just unplug the old and plug in the new, or do I have to do that where the computer hooks up??????

[Ourobos]

Unplug the O2 harness at the passenger fender apron, and at both O2 sensors, and plug your new one back in. The difference is the way the harnesses are pinned out.

[Incognito]

Unplug the O2 harness at the passenger fender apron, and at both O2 sensors, and plug your new one back in. The difference is the way the harnesses are pinned out.

This has some good info about O2 harness pinouts and configurations....

http://forums.corral.net/forums/show...hlight=harness

[xpkpremier]

Great that means I can keep my puter I just got yeahhhhhh Now I need a o2 harness for an 86 5 speed......

[xpkpremier]

What years will work for a harness, or will it be only 86 5 speeds only?????? I do have the OEM harness on the 86....

[xpkpremier]

Anyone,,,,

[Ourobos]

86-93

[Kerry]

I'm doing the samething you are, except keeping the aod. I have the same setup with an a9l currently. I was also led to the thread on corral. I posted up there with what i have. In that thread they said that just doing the maf conversion is not as big of a deal. the main concern seems to be on cars when doing 4cyl to v8 swaps. I was told the only thing i need to really do is check pin 46 on the harness side. With the ecu unplugged just need to turn key and see if there is voltage at pin 46. If there is voltage then you do NOT want to plug in the 5 spd computer. If you look at the corral thread posted above and go to page 5 you will see the latest info from where i posted my questions.

[banzaibullitt]

What's the link to it?

[Kerry]

What's the link to it?

link is in post #8 of this thread

[ngl9766]

That link is great although I am still not sure on what I need to do. I have an 86 that I converting over to maf and not too sure what to do about my o2 harness. Mine is an 86 that only has 3 wires. The computer I sourced is an
a9p from an auto untill I can find something better. Any thoughts on what I need to do to make this work. The car is a 5 speed....