I got a check engine light (P0128) code a few weeks ago. I researched it and it sound like a thermostat replacement is in order. The light stayed on for about three or four days and then disappeared. Hasn’t come back. I did not fix or replace anything yet. My question is once a check engine code is triggered does it stay on until fixed and reset or will it shut off after a designated period of time? Or is it possible the auto parts guy reset the system when I had it scanned. The light stayed on for a few days after it was scanned (I’ve read it could take up to 100 miles to fully reset).

Ive been watching the temp gauge and it seems to be functioning fine. Cold engine will get up to temp (180 ish) within a minute or two. Normal driving will hover between 185-200 degrees. If it does run hot (sitting in rush hour traffic) the fan kicks on around 220 and pulls it back down. Seems to be running just fine so the P0128 code has me confused.


Any any insight would be appreciated.

2013 Durango SXT. V6

 

the light will turn off if the condition that caused it is corrected and stays corrected for so many start cycles, 0128 is that the 'engine cold for too long' code?

if your not overheating i would just move on unless it comes back.

also of note, i wish mine would come up to temp that quickly in the winter, mine takes a couple miles of driving to get good heat, maybe its lukewarm by the time i get into the truck

 

I've got same issue (P0128). Came on in April while in Florida, went off but was saved and read when I had my oil changed prior to driving to Wisconsin end of April. Dealer in Florida wasn't concerned and said to monitor it. Since then it has come on twice and now I am taking it to an automotive shop this week to replace thermostat. Checked around and cost to do repair ranged from $170 to just over $300. Dealer in WI wanted $230 or so. I don't like driving a vehicle with check engine light on even though I know the issue, so will correct for peace of mind. I currently have 134,500 miles on my 2011 Crew with V6 engine and never replaced thermostat...must be time.

 

Just a quick followup to my previous post above. I took my Durango into a reputable automotive repair business (not dealer) after they determined it to be the thermostat opening way too soon and keeping engine from reaching correct operating temp. I had the code of P0128 and check engine light on. The cost for this repair was $150 and change. Dealer wanted close to $250 and another non dealer repair shop in the area was in the $300 stratosphere. It works and I can see the temp reading just over 200 degrees, not the 175 to 190 it was reading. This is the original thermostat and I have just under 135,000 miles on the odometer.

 

Yup it would have just got worse as it gets colder now . In the summer it's less critical .