ECM, throwing codes, or drivability wise; what happens to a TPI car if you just change the thermostat to a lower one without changing the chip? (180,170,160 degree?)

 

I noticed absolutely no difference driveability-wise between the 190 and 160 stats. I still hit closed loop. No codes either.

 

While you might not set any codes you can run into problems depending on what prom your using.

TCC, closed loop, CCP, EGR, all have temperature enables, so some may or may not work, properly.

 

i thought on GMForums.com u said that u had experienced coding throwings on every car u have seen this mod done to?

 

I have, I was just going to the people who can explain it better (our resident prom tuners) than I for an explanation and then going to post a link from here to there, for those who question the problems associated with this for you to see. but as you saw there was already others posting at the other thread that have seen the same thing I have.

 

:sillylol:

 

lol

 

I Changed to a 160 stat , and since then my car runs crappy. I am changing mine back to a 180 and see what that does. Its running very rich with the 160.

 

I've had a 160 stat in my car since 1990. I've had no problems at all with it in over 130k miles. The one thing I did do recently after finding TGO and getting my feet wet in prom programming and getting an autoxray unit was to scan the car and change the idle speed to 750 rpm instead of 800. The autoxray unit told me that at operating temp my car was running at, the requested idle speed was 800 rpm. I definately noticed the difference after I changed it, but I'm sure no one else would.

 

it depends on your climate but if the car runs like in the 170 or maybe even 160s all the time then the car may not run right and you will most likely see a drop in gas mileage.. the computer needs to work off engine temps that are seen with a 195 stat..

 

who is seeing codes, and what are they? what year vehicle? i dunno, i have been putting 180 stats in nearly every gm car thru my shop for at least 5 years, and prolly close to 10 years prior to that at other shops i worked for. the only one that comes to mind thats unique is the 2.8, 3.1 front drivers. vin "w" is one. only because the only stat for it is a 195. the stats even get a relief drilled in em for ease of filling and more importantly gives the steam (if formed) someplace to go, and be replaced by liquid coolant(read cylinder heads)-non reverse cooled motors. and i can honestly say that there has never been any problem related to the reduction of temp by 15 degrees. now mopars are a different story, you will always get a code but it wont illuminate the ses light, it will be there though when you scan it. i am really curious to hear what it is that is being seen by anyone and how it is getting tied in to a too cool of a stat. one thing-im with you on the 160 stat, too cool for stock, i have to agree.