Series of unfortunate events - Stillen SC Kit
 

Thought I'd share the struggles i've had with Zella at the end of the season in October through today, and my *hopeful* triumph.

I've got a 2010 with the Stillen SC Kit, currently running an Ecutek tune. Everything is essentially out of the box from the kit. I got re-tuned to Ecutek in spring 2016, and then was fine all summer long and put on about 2k miles.

Fast-forward to October. I got a fresh tank of gas and drove to a wedding for the weekend, using about 1/2 the tank to get there. (Indication that the gas was probably good at that point). Last night of the weekend I was driving home after a few drinks in a small town in Indiana near where I am from, and started getting the flashing SES light on my drive. Figured out that means engine knock, which really freaked me out. I limped it home and then got some octane booster the next day, which allowed me to get it the 2/5 hrs back to my actual house.

After getting home, I started to see the knock again and just shut her down for the winter. With some recent warm weather this past week, I thought I'd take another shot at figuring it out. After thinking about it more, I figured that it was either bad gas, or someone had put something in my tank (which i new realize doesn't lock like it is supposed to). I tried a few different methods to drain the tank, but ended up having to pull the fuel pump and siphoning from there.

I got everything back together, and got a small batch of gas from an oil company nearby that I figured would help rule out mechanical issues. (2.5 gallons of 90rec and 2.5 gallons of a special chemical blend 101.5 fuel). I put that in and now the fuel pump wasn't priming at all. A few more days of checking every relay and fuse known to man, and I'm stumped.

SillyRabbit from the forums came by today to help me look at it. We tried clearing codes, running fuel pump check and a few other things. Finally, I thought to pull the fuel pump again and see if I could identify a wire that was misplaced. SURE ENOUGH, the ground from the pump had come disconnected. Plugged her in and she fired right up. Took her for a 25 mile drive and no knock issues or anything, and the exhaust from that high octane blend smelled GREAT!

tldr; I had either a bad batch of gas or someone put something in my tank that caused engine knock issues. After a series of struggles, I was finally able to test with a good gas batch and i'm ready for the 2017 season! :driving:

Glad to hear you got everything worked out! Most likely it was a bad batch of gas because of the additives they add during the winter months. It's "suppose" to help keep moisture out of the underground tanks. Also, not all gas is created equal (don't use wholesale gas in performance cars, ex: Costco, BJs, Sam's Club, ect).

Got any data to back that up?

Here's what I found re: Costco

Is Costco Gas Quality the Same as Exxon, Shell and Chevron? - SavingAdvice.com Blog - Saving Advice Articles

AAA Study Finds Drastic Differences In Gasoline Quality

Yeah, that original batch of gas was from a place called GoLo here in town. Good prices, but not sure on the quality of their gasoline. It's weird that I went through half the tank before symptoms started showing though.

I've been using Costco gasoline for my vehicles for the past 5 years or so (~ 90% of the time) and have NEVER had any issues with it. I put it in the Z, my Jeep, wife's Sonata and my motorcycle and as far as I can tell, it is of good quality. I've used Sam's in the past as well without any issues either...

Costco is a Top Tier gas now. I use it exclusively in everything now

They must have upgraded the quality. About 3 years ago when I was running it, it kept pulling timing out of the car because it was seeing detonation, same with BJ's. As soon as I added octane booster, the timing immediately was put back in when I was logging it. I usually stick with the same gas station (Exxon) because I've had very good luck with it.

Good to know now though!

I think the quality of Costco et al gasoline is going to vary geographically buy supplier. Second tier stations are hit and miss. Sometimes may be perfect but next time not so much. In a sock vehicle unless it is really bad nobody would likely notice. However if you are tuned, especially FI, at a certain octane rating and it isn't delivered it can play knock knock ginger with you.

Have that problem even in the summe here running 94 octane from a premium station. It's good for the most part but has something like 10% rated ethanol but in reality the percentage varies. Apparently there is less oversight on fuels around here than have an ethanol content or something to that effect how it was explained to me from industry folk.

In any case glad you got it sorted and wasn't something mechanical needing attention!

Yeah, that makes sense that FI on a tune is going to be more sensitive to ethanol content. The blender for the fuel said he thinks it could have been the ethanol causing the knock from that intitial gas I had.

More expensive, but I may consider going with the 90rec (95 octane) without ethanol in the short term.

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So my 370 doesn't seem to care which station I use, two vehicles ago I had a Dodge Caliber, that I used to drive back and forth to work. My drive to work is 95% highway, which I just set the cruise and leave it (so it's very consistent, no traffic to speak of).

I found a 4 MPG difference between stations, that was repeatable. I would always do at least two tanks in a row and run them down as low as possible.

23 MPG - BP gas.
25 MPG - Speedway
27 MPG - Shell

I haven't subjected my Z to BP gas, but it doesn't seem to care about Speedway or Shell, gets the same 22.5 MPG no matter what (That's highway by the way too). Well up to 23 MPG now with the Stillen Intake...

Not while it may not be a quality difference, it indicated to me there was a difference.

So glad your back up and running!

Thanks!!

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