Plug Map Sensor In...car Cuts Off

Purdytang9

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Apr 12, 2017
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#1
Hey guys...i have bought an 88 lx and when I plug the map sensor In ( or should I say baro sensor sorry)...the car shuts off...if I plug it up and start it I ha e to push the pedal to the floor and it barely starts and I have to keep my foot in it to keep it going...i unplug it and the car still runs like crap but sounds a little better...can somebody please make some sense of this for me?...explorer headed and upper end liwer manifold...i had to run the act sensor to the air cleaner box...but the P.O. wired in a maf sensor but failed to put a a9l...so as of now I have a da1..so in theory I'm speed density and the car should depend on that map sensor..correct?...and the vac is hooked up..would that maf sensor being wired in cause all these problems?...im assuming the da1 don't see it...and it idles fine but try to give it gas it bogs..thanks In advance
 
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Purdytang9

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Apr 12, 2017
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#2
Oh yeah I forgot..i checked timing it's at 12...and when I take the spout out it seems to even run better...i thought it could be a ground (usually is)...but the car shuts off when I plug it in...i have a a9l coming in the next day or so and I'm hoping when I plug the maf in and change the map to a baro that it will straightin out ( But I don't think so)...sorry I was rushed last post and forgot this....
 

Purdytang9

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Apr 12, 2017
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#3
Oh yeah the parts ive already thrown at it distribtor, injectors, ignition switch,fuel regulator, plugs wires and cap...new iac, tps, ect, act, fuel pressure is good(39psi) I'm going to get a new baro sensor and pray...lol..

Sorry bout the 3 different posts...
 

Mustang5L5

Car used in adult film "Highway Gangbang-InDaButt"
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#4
What do you mean by "wired in a MAF sensor"? Did they pin it into the ECU? That requires moving some pins around, so if they put in a SD computer in the meantime, it's not going to run right at all.

If they didn't, you'll need to repin it before you put the A9L in. You can't just swap an SD computer for a MA computer and not make pin changes

Did you run the engine codes to see what the ecu doesn't like?
 

Purdytang9

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Apr 12, 2017
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#5
What do you mean by "wired in a MAF sensor"? Did they pin it into the ECU? That requires moving some pins around, so if they put in a SD computer in the meantime, it's not going to run right at all.

If they didn't, you'll need to repin it before you put the A9L in. You can't just swap an SD computer for a MA computer and not make pin changes

Did you run the engine codes to see what the ecu doesn't like?
Yes they did repin it...i mean he even ran the wire to the fuel pump and the vss...so it appears he new what he was doing..and I haven't been able to run codes...cant get it to orielys
 

Purdytang9

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Apr 12, 2017
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#6
What do you mean by "wired in a MAF sensor"? Did they pin it into the ECU? That requires moving some pins around, so if they put in a SD computer in the meantime, it's not going to run right at all.

If they didn't, you'll need to repin it before you put the A9L in. You can't just swap an SD computer for a MA computer and not make pin changes

Did you run the engine codes to see what the ecu doesn't like?
Yes they did repin it...i mean he even ran the wire to the fuel pump and the vss...so it appears he new what he was doing..and I haven't been able to run codes...cant get it to orielys
 

Purdytang9

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Apr 12, 2017
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#7
What pins should I have to run the a9l?...so I can go behind the P.O. and check to see if he did it right...i did see where he spliced it into 37 And 40... and looks like he pinned 9 And 50...and then from pin19 Gos somewhere under the carpet I'm assuming vss or fuel pump... but any else I should be aware of?
 

Purdytang9

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Apr 12, 2017
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#9
Thermactor?...i don't think I have them...im not totally sure what your talking about...is it possible he deleted them...the egr and smog have been deleted..a/c also...not much left but a couple sensors and a few vacuum lines...lol...ect is straight into the manifold...but what color wired should I have in those pins (38 And 32) and 3 And 6...thanks for your help mustang you really helped me out last time also...
 

Purdytang9

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Apr 12, 2017
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#10
So it wouldn't run right with the da1 with the mass air wire set up?..
 

jrichker

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#11
So it wouldn't run right with the da1 with the mass air wire set up?..
DA1 is a Speed Density computer.. You can't make a MAF work correctly with that computer.
It seems like I told you that once before in another post on the same subject...

All the following are mass air unless they say Speed Density
8LD - MANUAL 88 5.0L Mustang Mass Air - California
8LF - Auto 88 5.0L Mustang Mass Air- California
8LG - Auto 88 5.0L Mustang Mass Air- California
A9L - 89-93 5.0L Mustang 5-spd Mass Air
A3M - 93 5.0L Mustang 5-spd Mass Air
A3M1 - 93 5.0L Mustang 5-spd Mass Air
X3Z - 93 5.0L Cobra 5-spd Mass Air internally calibrated for 24 lb injector
A9P - 89-93 5.0L Mustang Auto Mass Air
A9S - 88 5.0L Mustang California Mass Air
C3W - 89-93 5.0L Mustang Auto
DA1 - 87 5.0L Mustang 5-spd Speed Density
J4J1 - 94-95 5.0L SVT Cobra 5-spd
T4M0 - 94-95 5.0L GT Vert 5-spd
U4P0 - 94-95 5.0L GT Auto
W4H0 - 94-95 5.0L GT
ZA0 - 95 Cobra R
D9S - 88 Lincoln LSC Speed Density
 

Purdytang9

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Apr 12, 2017
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#12
Sorry Mr Richker...i didn't know that I couldn't jump in on somebody's thread...so I made my own with a couple other questions I had...thanks for all the help...id be lost without you that's for sure
 

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