180 T-stat and P0128

[MyOhFive]

I'm running a Jet 180 t-stat and flexalite 183.. and my truck will periodically throw P0128, took too long to reach operating temp.

Thing is, the light will even turn itself off sometimes too, so I know it's not a continuous issue, just sometimes. I doubt my fan is set too low, my idle is 700RPM across the board. I think what triggers it is the mornings I luck out and get all green lights before hitting the highway, then jumping right on the highway. Too much airflow around the engine keeps it in warm-up mode too long. Make sense?

Is my only option a new higher temp t-stat?

Also how do I know what temps exactly my fan comes on and off at?

 

[RamRod37]

1 The MIL Light Will Go Off Normally After A Few Days But Code Still Is In ECM As Active Code And Light Will Return If Issue Does Not get Addressed in a few days mine has a misfire issue with Cylinder 1 that iv not fixed yet and that's the way it does I can Clear Code But After It Triggers the Light its Active Code till Cleared again and if I don't Clear Code it will go off after a couple of days but still active when scanned

2 what speed do you have you fan running on High Or Low Speed

3 the default T stat is showing to be 195 the computer is set for optimum performance of the sett temp so if your running a 180 this Is a good reason for it to be throwing this code If T stat was not doing this at first of install it could be stuck open or half open not letting it get to Operating temp as well id replace with the 195 with electric fan there should not be any kind of running hot issues

 

[RonJon '06]

When I asked Stu about putting in a 180° T-stat he told me it's better for the longevity of the engine to have it run hotter so I stuck with my stock T-stat.....still no codes.


EDIT: It would probably be better for the longevity of my engine if I'd quit mashing the pedal to the floor all the time too lol.

 

[MyOhFive]

I might buy a new one, not stock, but warmer

I still wanna know why I'm getting this code tho. Theres a lot of guys running 180 degree stats around and no one needs to have this issue.

Im gunna watch my temps with my InTune for a few cycles now. I'm certain my fan isn't coming on too soon...

 

[Harley Harrold]

I'm running a Jet 180 t-stat and flexalite 183.. and my truck will periodically throw P0128, took too long to reach operating temp.

Thing is, the light will even turn itself off sometimes too, so I know it's not a continuous issue, just sometimes. I doubt my fan is set too low, my idle is 700RPM across the board. I think what triggers it is the mornings I luck out and get all green lights before hitting the highway, then jumping right on the highway. Too much airflow around the engine keeps it in warm-up mode too long. Make sense?

Is my only option a new higher temp t-stat?

Also how do I know what temps exactly my fan comes on and off at?

I too have the Jet 180 t-stat and Flex-a-lite 183 E Fan kit. I set my controller to the center position, and I have never had a code pop on it. My idle is 800 RPM, and I let my truck idle for a couple of minutes before I drive.

 

[MyOhFive]

I too have the Jet 180 t-stat and Flex-a-lite 183 E Fan kit. I set my controller to the center position, and I have never had a code pop on it. My idle is 800 RPM, and I let my truck idle for a couple of minutes before I drive.

why such a high idle?

 

[Harley Harrold]

why such a high idle?

That is the normal idle for the 2007 5.7L Hemi, plus it keeps the oil pressure good, so no hemi tick.

 

[MyOhFive]

OK so... I monitored my ECT the whole way in to, and home from work today.

The way in, it was 62F outside, truck idled for 15-20 seconds before I left, then it was all green lights to the highway (love those days). But it rose to 180-182 effortlessly and stayed there the whole time. It dipped to 178 briefly, but didn't trigger a CEL.

The way home, same thing, minimal idle, right on to the highway, temp rose and stayed at 180-182 no problem.

When I got home, I jumped out of the truck with the tuner and listened for my fan to come on. It came on at 191-192 degrees, and I would love to tell you when it shuts off, but my heap of &*#@ing intune froze before the fan shut off. However, I never get the light when the fans are running, only while cruising. So after all my driving today, no CEL.

The ONLY other thing I could come up with is, when installing my t-stat, I followed a write up on here, and removed the little check valve in the t-stat housing, so there's an 1/8" hole that would always be allowing coolant to flow. But there is no freakin way an 1/8" hole is flowing enough coolant to slow down the warm up period that much, IS THERE??

Also, can someone tell me what the parameter is for max time before operating temp?

 

[chefred112]

what you need to do is get the tstat with the 'blocker' like the stock tstats. Autozones Duralast 4128 is a 180 that has it. If you compare with the Jet you'll see how much longer it is.

 

[Harley Harrold]

I installed the Jet 180 t-stat just as it came, un-modified, and I installed it with the small hole at the top 12:00 position. I have had no problems with the temp.

 

[MyOhFive]

Been monitoring my ECT and warm up time for the past 3 days on my intune.. of course it won't throw the code now. Behaving perfectly

 

[jmgak47]

It can be fixed permanently via the "blank"

I can't say because I am on lockdown on the forum.... But you probably can guess where the change needs to be done.

Jay

 

[MyOhFive]

uh.. what?

 

[MyOhFive]

Jay, email me

[email protected]

 

[chefred112]

hehe Jay

 

[Redtruck-VA]

I use a 180 with the piddle removed and have no codes. On my 03 I believe the temperature threshold is 160 degree. If it takes too long warming then the code. My normal temperature is 188 with a rare dip to 186.