About 2 months ago, i installed a 180 degrees t-stat. After that, my gas milage droped drastically(i filled up 2 miles after installing it) i was getting aroun 25-28 mpg to work and back, and it dropped down to about 20.
I drove it around for a little over a month like this with no improvement. I drive 100 miles a day, 5 days a week and every mpg counts, so because of this, i wanted my milage back, so i dropped the 195 degrees t-stat back in. Its been a few weeks now and my milage is still stuck at around 20 mpg. I was wondering if anyone know what the cause could be. I've had a full tune up within the last 10,000 miles, cleaned the tb, maf sensor, and air filter recently, checked for vaccum leaks, and yeaterday i hooked up a scan tool

LTFT and STFT readings were both right around 0%, 02 sensors were cycling good, and spark knock was at 0, so at this point i'm am confused at what would cause the bad gas milage. I drive an average of 55mph with cc set and have not had a lead foot. I have written down all scan tool data so if anything else is needed i will post it

When you say the O2'* are cycling good.. I interpret that as quickly. How high and low are the readings? Are you seeing 80-150 as a low number?

yes and around 800 or 900 as a high

What part of NH are you from?

Close enough that meeting up with the NE crowd to look over the car might be feasible?

concord area, about an hour north of the mass border along 93

Hmmm well..we are probably gathering at the usual place (aka my house) Saturday in Enfield CT on the MA border. You've checked for vacuum leaks and it runs great? Just crappy mileage?

yep, no vaccuum leaks, bad milage, no drivability issues, i wouldn't be able to make it down there for a while, my boss gave me a can of sea foam with a vaccuum injector so i'm gonna give that a try tonight, , and maybe use the moto vac tommorrow. If i didn't put on so many miles a week i wouldn't bother,

Check the reading for the Coolant Temp sensor. Are you sure your shifiting into OD?

coolant temp stays beyween 195 and 205 and im sure OD is working properly

i used the seafoam yesterday, and filled up halfway to work. Now i've only been 75 miles since i filled up and i'm already noticing a difference. Usually at 75 miles the gauge is halfway between full and 3/4th, and now at 75 miles its barley moved off of full, only time will tell, i'll know for sure if it did anything after the next few tanks, i'll keep you updated