ECU, Wiring, Sensors
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By thatboiE(g6)
#93015 So after a long time of looking on the internet and having little to no positive result for DIY's on how to wire a map sensor I figured that I give a quick how to (will post a full one when I take pic's)

If your engine (B16A) is one of the lucky ones to not come with a MAP sensor on the Throttle Body all you need to do is go to a junk yard and get the MAP sensor and wiring, you can cut it were it meets the main harness.

First unhook the ground from your battery, Next thing to do is to look on your engine harness plug (14 pin) on your strut tower, #'s 5,6,7, should be empty. On the firewall side of that plug will be three wires coming out (mine are #5,blue/green, #6,pink/white, #7,green/yellow). I was also using the stock cx internal harness.

(sorry for the big s**ty pics) notice the empty pins under the ylw/grn, orange/blk, white wires

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you can see how I cut the wires on the firewall side of the plug

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Next is time to splice. (on the fire wall side of the plug)

Cut #5,blue/green and splice with green/white from your Map sensor.

Cut #6,pink/white and splice with white also from your MAP sensor.

Cut #7,green/yellow and splice with yellow/red.

After the wires are spliced take the vacuum hose coming out of the throttle body where the MAP sensor should be and leads to the evap canister and cut it and make a "T" connection on it. Connect the MAP sensor to the "T" line on the vacuum line and make sure their are no leaks from the Throttle body to the MAP sensor to the evap canister. after all this is done reconnect the ground on your battery and turn your car on, their should be no more C.E.L. code for #3.

Did this quick so the install isn't the neatest sorry.

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Thats a real quick explanation of how to do it any questions just ask.
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By Classiccarsrule85
#93020 its a nice write up tho some of the pictures need well help pointing out what you are showing with them....

but quick question couldnt you of just changed the tb to one that came with a map sensor i know most d's and b's are interchangeable....so there had to be one at the junkyard...
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By thatboiE(g6)
#93021 yes you could have but the biggest problem you will have is not having the actual plug for the MAP sensor, cause the engines that have the Map sensor on the fire wall uses a different plug than the strut tower main 14 pin plug, hence the #'s 5, 6, 7, being empty, so if you went to a junk yard and bought a T.B. with a MAP sensor on it you still don't have a plug to plug into it, that's why you need to wire a MAP sensor plug into the firewall side of the harness, that leads to your e.c.u. so you can actually plug the MAP sensor into. dose that make sence? it's kinda hard to explain i guess.

So if you go to the junk yard just get the MAP sensor AND the plug with as much of the wires as you can so you can wire the plug into the internal harness.
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By suspendedHatch
#93023 Wouldn't it be a little bit cleaner if you got one of the MAP sensors that mounts to the fuel filter bracket?
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By thatboiE(g6)
#93115 that too was a problem I didn't know where to find one.
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By thatboiE(g6)
#93407 My old motor was a 95 cx non v-tec D15 P.O.S. and the MAP sensor was on top of the throttle body, in fact I've never seen a fuel pump mounted MAP sensor except in photos. You find one and ill buy it off ya, or trade you something!
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By Tristanw10
#183778 I have my map sensor hooked up to the vaccum line on my fuel rail, is this the wrong routing aand is it gonna cause an idle problem?, thanks
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By suspendedHatch
#183868 The vapors from the fpr will destroy the MAP sensor.

I never understood why the OP's car didn't have a MAP sensor plug. All fuel injected Honda motors have MAP sensors. The only other way to run an engine is with an AFM (which is the big metal box on the intake pipe you find on other cars like Toyota etc).
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By Tristanw10
#183923 Damn, thanks man I had no idea it would do that. I will route mine the way it is shown in your DIY, thanks.
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By gothemsea
#229750 hey my map sensor have diferent wire color can u post a pic of the map or explain which number go with the color ??
thanx