Map Sensor Problem w/ JDM b16

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J240sx

New Member
I have a 92 EG Hatch with a JDM B16. My problem is that there are 2 map sensors. One is wired directly to the ECU and the other is from the wiring harness. Its a GSR harness and for some reason Vtec will only engage with the Map sensor that is directly from the ECU is hooked up. But the car will not idle and I have to rev it to keep it idling but Vtec is there so I don't mind. If i plug in the other sensor the car will idle just fine but Vtec won't engage. I've tried having the VTec Map plugged in to the Throttle Body, and the Wiring harness Map plugged into a sensor but just kinda hangin towards the back of the firewall. But the car will smoke bad and the car still won't idle and Vice Versa with the Sensors being plugged in the other route. I've thought about Splicing the two sensors together and making one but i'm not sure I want to go that route yet. Also I am running A P72 if that info is needed. Also Code 3 which is map is always on unless I go with the two sensors plugged in at the same time. Any help is appreciated.
 
You should have skipped the gsr harness for one. Your stock harness would have worked just fine with a jumper harness for the ecu. What year integra gsr did the harness come out of? And what ecu are you running? obd1 or obd2?
 
The car is going to smoke bad and also run rich plus idle evenly, but high because its not getting the MAP signal to the ecu. Your vtec will only work one way, because its not wired into that harness correctly. I need more info to diagnose it though. Pictures of the clips would be great as well. Keep in mind, gsr's all have a knock sensor. If I remember correctly, jdm b16's do not.
 
The harness came with the shell. Its an OBD1 with a P72. The ECU does call for a Knock sensor and the JDM B16's do come with with one but mine doesn't have it. I do get a code 23 for knock but VTEC will still engage. The car does run extremely rich and smokes at times too. I was beginning to think that it was the valve seals but when ever I run it in the non-Vtec mode it won't smoke. The clips are both the same as all others that would go into the MAP plug in. One comes from behind the battery tray that goes directly to the ECU and one comes off the Harness. I agree that its probably not reading off the harness. The car will foul out plugs quick and I think its got alot to do with the MAP. The car seemed alot quicker when I first got it running and lately it feels like its lagging alot because of the Rich Mixture and fouled plugs. Any help is appreciated. thanks.
 
Man your in a world of headaches. Your map sensor reads vacuum from the throttle body but 1st gen b16 manifolds have that nipple for the vacuum line on it for the map sensor. That is the only map sensor you should be running and it should be wired into the engine harness only. your obd1 gsr ecu will look for knock because all gs-r's have knock sensor's, your 1st gen b16 does not. I would try to get a chipped p28 to run b-series and sell the p72. Or keep the p72 and have it socketed for crome or hondata and have it tuned, that would be the best thing to do, but the most costly.
 
Well I'm currently running a P30 Manifold (Del Sol Vtec) which works fine. My B16 has the socket for the Knock Sensor on the motor but the Plug & connector aren't there. I'm actually thinking that I have the Civic Harness because I noticed I don't have a plug for the knock and also I asked the guy who sold me the shell. See i've been told to just get a P28 chipped but will that solve the issue of the 2 map sensors? See the car pops TEC when I have that sensor from the ECU plugged in and I kinda got it idling by turn the Idle screw on the Throttle Body. But the car still smokes at times and like you said its the Map sensor, the computer only reads the Map being hooked up when both are connected. Last I tried that though the car smoked bad. Also coming up with a P28? We put in my buddies chipped P28 and the car ran damn good. I'm leaning towards the P28 but I need to know if it'll get rid of the Map sensor issues anyway the car will run better and probable be alittle quicker with a Chipped P28. Let me know what you think.
 
Get a chipped p28 with a mild program, since your engine is a stock b16. As for the map sensor, you need to get wiring diagrams and make sure its wired correctly. There should only be ONE map sensor.
 
Well the car isn't stock. I have a JDM B16 I've gone with 11.8-1 High Compression Pistons, Eagle Rods, and rebuilt the rest with O.E parts. I'm planning on going with a Type R Cam and Fully adj. gears and then going P28 with a good tune. I'm going to have to try a differen't wiring harness. But thanks for all your help I appreciate it.
 
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