Screw that just hollow that pig out and call it a day ... Upgrade enough for me lol. I can't remember for sure but you test the O2 sensor for Voltage I think... Shouldn't be a massive amount of voltage but I'm pretty sure it's DC volts...

 

First you don't want to hollow out your CAT it will actually degrade your preformance not increase it. If it is the CAT just upgrade with a High Flow one. There was an article in Sport Compact Mag about 3 years ago that addressed that and I know a person who did it and his performance went down, not up.

OK to test with a multi-meter First get a Haynes manual so you know what pins you will need to hook up to. I don't know for your car. You need to find the DATA pin and GROUND pin (Usually pin 1) now that you have the pins found set you meter to DC Voltage. Voltage will not go over 5 so a setting close to that will work. Put the black test lead to the ground pin and the red lead to the DATA pin. Have a helper turn the car on but do not start. you will see a raise and lower on the voltage. You want to count the up spikes. For example. IF the error code for a bad ECU is 000 you would not see the voltage raise at all. If your code was 007 then you would see no voltage a raise and fall then another rise and fall. That is the binary code for 7 (though I might be wrong its been a while since I have converted binary[8D]). the interval between binary bits is about 1 sec. if after 3 to 5 secs you see it rise and fall again that is a second code. To see the code again you will have to turn the car off then back on. The Haynes book should have the waveform (used if you have a ociliscope) and output signals for this kind of test. The book can also explain the test in more detail this is just a quick and dirty version

 

Hello guys needing help on my 94 GS. Check engine light comes on then goes off after about 4 minutes... it stays off for about 5 minutes then comes back on and stays on. I was told the 94 model doesnt have an OBDII instead it uses an OBDI. I do not think any Auto, Zone Advanced or Pep bos have a OBDI scanner. Would anyone be able to tell me where I can rent or buy an OBD scanner or would it be less expensive to just have it done at a shop. I own an OBDII scanner already but it is useless on this car. I am a newbie on this forumbut I am a member of the Nissan Forums, Toyota Forums and BMW Forums since I also own a 95 Nissan 200 SER, 2002 Toyota Tundra and a 1998 BMW Z3 and have been able to get a lot of help from those boards/foums I am faily knowledgeable and have a fairly well equipped workshop in my basement.

 

Why are you posting this in here? [sm=chairshot.gif]