Am I crazy or does my grade of fuel effect my engine temp? I swear that when I occasionally run 87 octane for a 1/2 or 1/4 tank my engine temp goes up 5 to 10 degrees. Is that a total coincidence? I usually run 92 octane.


2000 D2 approx 150,000 miles

 

It adjusts to run the lower grade fuel, and could be running leaner which could lead to a higher temp. I would just run 92 all the time.

 

Thanks for the reply. Yes I normally run 92 but sometimes in between fill-ups when I need to throw 20-30 bucks in I run a lower grade.

 

I've recently been experimenting with octanes, and while I have seen a significant change in MPG, I haven't seen temp changes.

 

Life was a lot easier before I bought a scan gauge. now I'm constantly looking at the engine temp. Ignorance is bliss.

 

Could be that radiator is clogged up. So what would be a minor change to someone else becomes larger to your scan gauge as engine is just barely staying cool. On the bleeding edge so to speak.

 

a higher octane fuel will burn hotter, but if you cooling system is up to par you should notice.