https://www.tamparacing.com/forums/n...help.htmlFound the problem, now need opinions. 4 core radiator, Mishimoto dual 12" fans wired w/ the ignition, no thermostat, new coolant temp sensor. I've been running like shit because of the weather. I just realized that when the cars' temp is below 135\40° my afr is substantially below 14.0 and runs like shit. But since today has been warmer out more than most days, my temp has been above 140° for the most part. Meaning my afr has been in between 14.5-15.2 and the car fucking lives boost now. I know this isn't rocket science, but what would be the more logical solution?

 

Install a thermostat or fan controller?

 

I would install a thermostat and see where that gets you. A thermostat does serve a purpose, it keeps the car at optimal operating temps, and helps regulate flow in the cooling system. Most likely messing with the CTS causing it to run like poo, I would wire your fans correctly also.

 

I figured the thermostat would be the first said thing. Should I use the OEM one or a slightly higher temp one? As for my fans, they are wired correctly to my standards, just not temp operating standards. How else would I wire them to function off of a certain temp operation?

 

Probably won't matter, just make sure its OEM not Autozone junk. For the fan controller: DIF Dual Fan Controller Install on S13 S14 240SX

 

Not even Advance on the thermostat? And is there a cheaper alternative to the DIF? That thing is pretty pricey.

 

I have had shitty luck with non oem theromo's. Some were stuck closed out of the box and I have had some that have worked perfect. Needless to say I learned my lessons along the way, OEM all the way on important parts.

Let us know how it works out.


Edit: I will try and find you a write up for wiring your fans to the CTS. Not sure where I have it saved on my comp.

 

intake air temperature sensor is probably bad. (don't remember what it is actually called)

what do you have in the way of tuning?

there are plenty of cars that drive around without a thermostat,
Does your engine get to operating temp?
while I do agree, that can cause issues since your operating temp is inconsistent, after letting the engine run for a while, and the block warming up, the entire system is heat soaked anyway and if the temperature isn't running away, then chances are, it is maintaining correct (or close enough to it) operating temps. If the problem is still there once it gets warmed up, then I would bet that the ECU doesn't know how hot, or in this case, cold the air is that is coming into the engine. It probably thinks that since the MAF sensor is getting colder, that more air is flowing in than it really is, and that is causing your problem.

 

^

Are you speaking about the IAT sensor, as far as I am aware that is a diag tool. Which I believe is also not used in Martins ROM tunes.

My bet is thermostat and or CTS. I would almost be willing to put money on it, the way he is describing the AFRs related to temps.

 

Air intake temp sensor?.?.?. I'm not familiar w/ that one. Where is it located? I'm running a ROM tune from Martin. I've always ran w/o a thermostat in my s-chassis's. Really not that important in FL. Here's a run down...I went ka-t in Oct of 2010. Back then, I had an OEM radiator and a single 10" fan. Everything was fine during that winter. Spring of 2011, I put in a 4 core radiator and 2 8" fans with a shroud that was 1/3 of the height of the radiator. All this time, still no thermostat. I didn't have an aftermarket temp gauge so I was going off of the one on the cluster. It was for the most part at the half way mark when I was driving. Everything is still fine for the most part. I picked up the Mishimoto dual 12" fans not too long ago, (right before shinmei went to Japan...however long ago that was). By now, I've had a coolant temp gauge and this so-called winter, I've been running between say, 100°-130°. Not ideal operating temp now that I realize it. Today was fairly warm out today and my engine temp was right above 140° and the car ran just fine. Just over an hour ago, I drove w/ my fans plugged in and the average temp was 126°, and the car ran like shit. I unplugged the fans, let the system heat up to 150° and the car ran perfect. So, being that the car never gets to normal operating temp when it's cold(er) outside, the coolant temp sensor isn't responding correctly because my coolant system is pretty much below it's normal operation....if that makes sense, and causing me to run rich(er)