180 T-Stat Causing P0128 Code

[18forever]

I've been on Challenger Talk and no ones got any suggestions maybe you can help. I've got a 2009 Challenger R/T and Predator with latest crom installed. I've installed the 91 CAI tune and a 180 t-stat. I've changed the fans to: no A/C HS 195 LS 190 and w/A/C HS 195 LS 190. The MS setting on both are 195. I keep getting a CEL code P0128 "thermo broke". Through all the forums and threads I've read some people get this code and some don't. I checked my data last night. After a 20 minute drive at 60 mph I pulled in the driveway 2 ft from the wall. Air temp was 78 and ECT was 188. The fans weren't running at all and the temp never went above 188, if I increased RPM the temp went down to 184. Any suggestions to keep the 180 and get rid of the P0128 code?

[Mike_Levy]

Lower your fan turn ons. I use 181 for the low speed, 188 for the medium and high.

[white_lightning]

depends on what type of stat you used too. did you use one that has a bypass blocker?

I am using a Jet 180*, part# JET-10183 which looks just like the stock thermostat. engine warms up much faster than with the regular style 180* stat I tried first.

PCM can have a P0128 over 2 things:
engine temp too low
engine takes too long to warm up

[18forever]

First to Mike: How is lowering my fan temps going to help the engine warm up? The problem is the temp isn't going up fast enough or hot enough, that's whats setting the code. The PCM thinks the thermo is stuck open. Second: the thermo I put in the car has no bypass hole I can find and it's a Mr. Gasket part # 4367 180 degree. What I don't understand is why it now takes longer to get to 180 degrees. Whether the thermo is 180 or 206 the engine should warm to 180 in the same amount of time as the 206 regaurdless of when they open they should get to 180 the same. That's not happening, it takes longer to get to 180 with the 180 as it does to get to 180 with the 206. This makes no sense!! After 180 is reached then the warming time sould be different between the two, but not on the way there. DS has been talking about doing something to help us out and I was hoping I might get some answers or suggestions here, but I guess not.

[neidan]

I agree with white_lightning. Your T stat does not have a bypass and so you are taking to long to warm up. I believe if you slap a Jet in it, you'll be fine. I have the Jet WITH the bypass. (they make both types) 10183. No issues even in much colder temps. I do let the car warm up for a few min before driving...

[Mike_Levy]

It won't help it warm up faster, it will keep it cooler. Your temps are too high. Lowering the turn on temps won't solve your problem, but it will take full advantage of the stat.