Hi. 1998 DOHC Saturn. 142,000 miles. Went from using 1qt every 5,000 to 1 qt every 750 overnight [well, over the course of a trip to Florida from NY.] Anyway, I'm 400 miles into the clean phase, and it has used a little bit of oil, maybe 4 oz, just enough to see the level drop on the stick. I'm happy about that. Now my question, since I started using Auto RX, gas mileage has dropped. Down to 27-29 highway. Used to get 35. Any ideas? Coincidence? Has anyone seen this before? If it's been seen before and is a temporary situation, I'm ok with it. If nobody's seen it before, I've got another problem I need to figure out. Air filter is clean, new plugs when I changed the oil and added AR, tires properly inflated. I appreciate any ideas anyone may have.
PS, also added AR to my F150, just to be safe...cars are too expensive.
History on the Saturn, got it from my sister who bought it new and had it maintained by the dealer. I changed the valve cover gasket and it didn't look too bad. Some varnish, but no sludge or black deposits. That was 85,000. I used nothing but Mobil 1 every 5000 w/Pure One filters since. Has been OK until now.
I would start by checking your PCV Valve and if it has not been replaced then go ahead and put a new one on.
I would also check your PCV hoses to make sure they are clear, I would just do the Clean and Rinse phase and keep an eye on the oil level. It might not be a bad idea to get some extra oil filters and too change them halfway during the Clean Phase and again halfway through the rinse phase.
What brand of oil are you using for the Clean Phase, hopefully it is dino oil, same thing for the Rinse Phase.
Did it use a quart of oil before the Clean Phase.
What type of oil did your sister use in this car, I would not go back to synthetic oil until the oil usage is cleared up, meaning after the Rinse Phase is over I would run a dino oil for 1 to 2 oil change intervals.
Are you burning oil or leaking oil, because there is an auto-rx application for seal leaks, and an application for oil burning.
That's good news, ARX helped my girlfriends Corolla with an oil usage issue, didn't completely solve it(flawed ring design on these cars) but helped and the cars runs really well, just about to turn 150,000.
For Saturn tech issues, I would go here: http://saturnfans.com/forums
Start with the sticky threads and search the forums. There are a lot of ways to degrade fuel economy. Start with obvious stuff like whether you have low tires, etc....
