I have a 1999 Durango, recently the check engine light activates and the engine temp gauge moves to the top. There is no heat in the cab. This happens only during city driving, when driving on the highway everything works fine. No gauges say over heating or to check engine. Does anyone have any ideas as to what the problem may be and if I would be able to fix it myself? Any help would be great.

 

Sounds like the T-stat to me that's exactly how mine crapped out on me. Make sure to get an OEM replacement I have had problems with others too many times.

 

I have the JetStat 180 degree replacement from Summit Racing. It is the same company that makes the Jet Chip stuff. It has been fine/excellent.

IndyDurango

 

Yeah I've heard good things about them. I replaced my 2nd t-stat with a failsafe 180* t-stat and had to replace it within 2 weeks because it failed... I went back to OEM.

 

napa 180 deg t-stat... never has failed me yet.

 

Yeah I figure I'll go back to another 180 one of these days but I lost a little mileage with the 180 when I put it in and the power gain was very small hardly noticeable at all. Maybe after I get a programmer and exhaust.

 

there's more to it than the mileage loss, there is the issue with the heads... just my theory...(on the heads, I think the 180 t-stat helps prevent the cracking problem from poping up)

 

There is certainly some validity to that statement.

The 360 was an engine designed many years ago. 160 and 180 stats were common then. 195, 205 and higher now are more for environmental EPA stuff rather than what is best for the engine. Thus, the lower stat temps probably get the motor closer to where it was originally designed to operate.

Since the heads are part of the engine, they too should enjoy the lower stat temps. We just can't go all the way down to 145 or 160 because the computers in the vehicle will not act properly, instead reading as if the engine is running to cool and it will dump more fuel and try to continously compensate... ala like running with the choke wide open from days of old too. So we come full circle.

As for what the EPA thinks is best, [:'(] on them

IndyDurango

 

I think the higher temps are ment to help burn off more of the mixture. now 100% sure on that but it sounds good

 

As emissions are getting more strict in the Dallas Fort Worth area, I worry if I will even pass inspection by going to a 180 stat! These D's pollute enough as it is, drinking gas like no tommorrow!