jesusno2 Posted February 14, 2009 Report Share Posted February 14, 2009 Well almost gotta figure out how to mount the air temp sensor in a round tube some how? Quote Link to comment
yello620 Posted February 14, 2009 Report Share Posted February 14, 2009 Is it a threaded sensor or does it just push into a rubber grommet? Quote Link to comment
Icehouse Posted February 14, 2009 Report Share Posted February 14, 2009 I never hook up the air temp sensor... Well I did on my truck but not on any other swap I've done. Quote Link to comment
philcas1987 Posted February 14, 2009 Report Share Posted February 14, 2009 That air temp sensor is not needed. It has to do with some emissions junk. It made no diffrence on my car plugged in or not plugged in. The only thing is that the ecu throws an air temp sensor circuit code everytime you go in self diagnostic mode. Quote Link to comment
Creepy Cruiser Posted February 14, 2009 Report Share Posted February 14, 2009 What year & model is the intake tube that you started with there made for, and what brand & model is it. Quote Link to comment
jesusno2 Posted February 14, 2009 Author Report Share Posted February 14, 2009 Well if the air temp sensor does nothing how does the ecu know when to lean or richen up the mixture?? Quote Link to comment
yello620 Posted February 15, 2009 Report Share Posted February 15, 2009 Thats the job of the oxygen sensor in your exhaust pipe. Quote Link to comment
jesusno2 Posted February 15, 2009 Author Report Share Posted February 15, 2009 I thought it was a little bit of both? Incoming air and out going air no? I think I might make a plate and weld it to the intake so I can keep it. Not sure though yet I can see what it does without it I guess. Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 I've never heard of an EFI system that doesn't require the intake air temperature. That is what the enrichment is based upon. ie: startup in cold weather... Quote Link to comment
fastdadd Posted February 15, 2009 Report Share Posted February 15, 2009 air temp sensor acts like a choke plate giving more fuel when cold but not always needed Quote Link to comment
jesusno2 Posted February 15, 2009 Author Report Share Posted February 15, 2009 I've never heard of an EFI system that doesn't require the intake air temperature. That is what the enrichment is based upon. ie: startup in cold weather... Exactly what I was thinking your just explained it better Quote Link to comment
BEEBANI Posted February 15, 2009 Report Share Posted February 15, 2009 I'm not running mine either. It's not as big a deal on the OBD I motors. My '97 wouldn't run worth shit without it, it was OBD II. Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 I'd love to see a definite explanation of how the IAT sensor is not required. Every standalone EMS out there requires it. Otherwise, the ECU has no way of knowing how to handle enrichment.. Quote Link to comment
BEEBANI Posted February 15, 2009 Report Share Posted February 15, 2009 I'm sure your right Steve, but I haven't seen a significant difference without it. Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 fair enough. Quote Link to comment
datzenmike Posted February 15, 2009 Report Share Posted February 15, 2009 (edited) The older 280z/zx 200sx with batch fire injection used air temp input to the ecu to help calculate the mixture. I can't find the equivalent on the KA motor possibly because it is strictly controlled by the O2 sensor? All use a water temp sensor to know if the motor is cold and an air regulator valve to speed idle and warm up. Edited February 15, 2009 by datzenmike Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 Ahh... so the water temp is the temp they are using. Thanks Mike! Quote Link to comment
heirfaus Posted February 15, 2009 Report Share Posted February 15, 2009 (edited) I'd love to see a definite explanation of how the IAT sensor is not required. Every standalone EMS out there requires it. Otherwise, the ECU has no way of knowing how to handle enrichment.. WOW, I just read this thread and am SHOCKED at the lack of knowledge, or desire for it, by some members. I'm with you Steve. EVERYONE else who disagrees needs to take an engine performance class at your local community college or something to get up to speed. Edited February 15, 2009 by heirfaus Quote Link to comment
heirfaus Posted February 15, 2009 Report Share Posted February 15, 2009 ECU uses the air temp to correctly match the air density with the proper amount of fuel. 100 degree F air needs far less fuel than 15 degree F air. Without the air temp sensor the computer uses a generic number to continue running as close to normal as possible, but you are FAR from optimal. I guarantee if you put a wideband on it wouldn't be correct. And if you want to try and get maximum power...well forget about it. Where are you? 14.7:1, 12:1, 17:1, you have no clue where you are. Also the oxygen sensor doesn't control things. The O2 sensor only fine tunes the mixture. That's like punching yourself in the face and then saying, "well that hurt, I'll try it differently next time!" You don't fix the problem after it's wrong, you correctly calculate how much fuel the volume and density of your air needs beforehand. Quote Link to comment
jesusno2 Posted February 15, 2009 Author Report Share Posted February 15, 2009 I kinda figured it needed to be their. Nissan didn't put it their just for looks. I didn't know the whole story behind it like chris mentioned, I just know the ecu has to have some kinda of knowledge of in coming air temp. The exhaust gets hot way before say a gallon or gallon 1/2 of water gets hot. Could explain why I have read people complaing of terrible gas milage and poor running?? Even with the air temp sensor hooked up does not mean it is doing its job and working corectley anyone know how to test that sensor? Quote Link to comment
mafoose Posted February 15, 2009 Report Share Posted February 15, 2009 Somebody woke up on the wrong side of the bed! If it's like early Nissan EFI, there's most likely an IAT in either the AFM, or it has a MAF sensor that could calculate air density since it measures temperature drop between heated wires. It's also very likely that the other airtemp sensor is purely for emissions which is why it's by itself because it was probably not necessary to meet the same emissions everywhere in the world. Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 That seems logical! Quote Link to comment
philcas1987 Posted February 15, 2009 Report Share Posted February 15, 2009 The obd 1 ka24e relies on the coolant temp sensor, the maf sensor, tps sensor, and the cas sensor in the distributor to meter fuel and timing. You guys are making such a big deal on a sensor the single cam obd1 ecu does not need. As far as I know the early 89 ka had no iat sensor, high compression pistons, diffrent injectors, and better fuel and timing maps.the late 89 to 90 had to better meet the emission laws of the time. The main thing jebus has to worry about is, getting a new coolant sensor , new o2 sensor, properly adjusting the tps, correctly set the timing, and give the maf a bath. Quote Link to comment
slodat Posted February 15, 2009 Report Share Posted February 15, 2009 Thanks for the info Phil! Quote Link to comment
hessianben Posted February 15, 2009 Report Share Posted February 15, 2009 (edited) The air intake sensor doesn't have to be threaded in- it just needs to be in the intake flow. I used the stock rubber grommet and drilled a hole in my custom intake, just pushed it thru. IMHO, it doesn't make a huge diff in how the engine runs, unless youre really trying to make use of a good cold air charge. Edited February 15, 2009 by hessianben Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.