I have a 1999 Doge Durango v8 Magnum 5.9 l engine. Gassed up the other day, recall confusion at the pump selector, probably put in e88. Within a few miles driving, normally smooth running engine started grabbing, bucking. Engine light on =code P0305, cleared it, ran at <40 mph speeds fr a day, generally OK, then highway and Check Engine back on after new round of bucking. Can I just run it out or do I need to have it drained?

 

Just run it out while continuing to refill to dilute it.

 

Yeah I would attempt to run it to half full then top it off with 100% if you can find any. That should bring your ethanol percentage down low enough to at least get it mostly normal. Then run that tank to the empty line and refill with your normal E10 or whatever they do in your area.

 

It's funny that my 2001 Durango R/T uses Premium fuel, yet my brother's 99 Dakota R/T uses Regular gas. Aren't they the same engine? You can always get a cheap hand operated transfer pump at Harbor Freight and just drain your tank. Or just siphon it out with a piece of tubing. No need to drive it to empty the tank.

 

Yes they are. As well as the same engine that's in my 98 that's not an R/T. But dodge programmed the computers different for a year or two to require premium fuel on the R/T's only.

 

If you put regular gas in a premium fuel car it will simply pull timing to make up for it.

I believe that E85 compatible systems can supply more fuel when running E85 as you need to burn more of it to make up for the lack of energy it has compared to gasoline.

 

That assumes the engine has a knock sensor, so it can actually tell what kind of fuel it is trying to run..... I don't think dodge actually used them on the 5.2/5.9 engines, maybe on the 4.7.....

 

Put some octane boost in it as well.

 

You know I did simply assume that everything OBDII had a knock sensor but I do believe you are correct so I have to take that one back.

 

That's what I thought too.... until I went looking for it, and couldn't find it.... Imagine my surprise. Seems to me that that one little sensor cures a lot of ills, and allows you to squeeze a bit more power out of the motor, without any additional effort. I am real curious what dodge was thinking when they DIDN'T put one in...... I mean, seriously, my 88 OBDI Firebird had one.... not likes it's "new" tech or anything.......