Ok first of here’s all the car info. It’s a 92 Eg Hatch with a B16a3 running on a chipped P06. Since I’ve bought this car it’s had it’s set of little problems because I bought the car already swapped and it wasn’t exactly done the best way. So here’s my issue currently. My car starts up almost first turn every time and drives, idles halfway decent but a touch rough. When I’m driving it as long as I’m giving it power it goes pretty smooth but once I’m cruising and trying to hold one speed I can hear it kinda sputter and hiccup a bit but if I start giving it more gas it’ll stop. The car is running rich but I thought it just needs a new tune which I’m currently working on getting money for since the Ecu I bought was already chipped and tuned on another car. (Yes I know that’s not the smartest idea but the previous Ecu was entirely wrong for the setup and ran like trash, like I said I didn’t do the swap I’m just fixing what I can now) So yesterday I wanted to try and make sure it was just the tune that’s making the car run a little rough and I checked fuel pressure which is steady at about 30-32 psi. And then I thought the map sensor could probably be bad so I got a multi meter and tested it and from everything online it says you’re only suppose to get about 4.7-5v to it but mines getting a steady 9.6v. (Im not sure if that’s a problem or not) and like people said to test it I ran the pressure up and the numbers never changed. My reasoning for telling all this info is so someone can maybe shed some better light on what might be going on. Im pretty sure a new map sensor would clear the whole issue and it’ll probably run a touch rich still since I have yet to tune for my motor. But my question about the map sensor is I live in Hawaii and the parts stores charge about 150-200$ for a stock map sensor but there’s some people around selling aftermarket 2bar and 3bar sensors for way cheaper then a stock one. Could I just buy an aftermarket one from someone without having to tune it right away or would it basically not make a difference running an aftermarket 2/3bar vs the one that doesn’t read at all. Whatever insight someone can give would be much appreciated and if more info is needed or something clarified just ask so I can get the best help possible. Thanks

 

The ECU supplies a regulated 5 volts to the sensors (MAP, TPS, IAT, and ECT). That is important. If the sensors are getting other than 5 volts, probably the ECU is bad, or harness is miswired.

 

I am Orig owner of a B16, had the top end rebuild done, then needed the PCV valve and canister replaced. now it is running so rich it fowled a set of plugs and latest symptom is after driving a short time 5 min, stopping, engine off and starting again, revs oscillate from 500 to 1500. to check the voltages (MAP, TPS, IAT, and ECT) do I do ti with key on, motor running, not running?

 

key on