Swapped A Pro-m Maf From A 96 Gt Into My 91 Gt

I installed the injectors and maf sensor i disconnected the battery to reset the eec. Now the engine wont idle and it falls on its face if i give it to much gas. Checked my vacuum lines and all me connectors. Any clue as to what im missing
 
Ok I was under the impression that only yr 94-5 maf was compatible. The 96+ were not and needed a tune for them to work.

That aside what does your set up look like? Is the filter attached to the maf or is there tubing in front? A pro m or even any maf for that matter needs 6" if straight pipe to promote smooth air flow. Turbulence will cause a bad reading and the symptoms you are describing. Part two of this, pro m used to etch what the unit was calibrated for on the side of the housing so if it is indeed calibrated for 30s there should be a 30 somewhere on the unit. Lastly pro m will take back any of their meters and recalibrate for a fee. I think it's around 80 dollars.
 
To the first question......yes the filter is directly bolted to the maf and i do have a tube between the maf and throttle body of at least 6" straight tube.
The calibration is etched with 96gt30
I have heard the same about pro-m recalibrating the maf for around 80 to 100
I guess i will send it in to be recalibrated
 
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The MAF may not be working correctly or you have some other problem. Dump The codes and see.

What mods do you have that make 30 LB injectors necessary?


Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

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If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

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The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

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The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10
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Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Equus Digital Ford Code Reader (3145) Equus - Digital Ford Code Reader 3145.
It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.
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