(2010 ss/tc full bolt ons and trifecta 22psi tune) so as the title says I'm wondering if i have a batch of bad gas. car was running fine on thursday and it was the long weekend here so i decided to take my car to my home town (5 hr drive) so i filled my car up with 91 and i never got 10 min outside the city when my check engine light was flashing and the car was running like crap. but then she ran fine for another few min and pulled great and then the check engine light flashed again and ran like crap. it continued like this until i turned around and went back home. when i got home i checked the codes and had a misfire on 1 and 4 so i changed the plugs and gaped them to .030 and swapped coils around to see if it would misfire on the other cylinders. misfire stayed on 1 and 4 so i done a compression test and had 150-160 on all 4. so do you guys think i have a batch of bad gas? what could i check next?

 

I love how when some one gets a SES light they think to do a pull lol.


You getting knock?
Sure you put in the right gas?
Your tune for 91 or 93?

 

didn't do a massive pull just went into boost a bit maybe 4 k rpm . knock stayed between 0 and 4 on the rpd. I'm on 91 tune and I'm 110% sure i put in 91

 

It's possible that 87 was put in the 91 tank by mistake, iv heard of that before. Drain ur gas some how or add some octaine booster or something and see how it is then. Or flash back to stock and see how it works. I wouldn't fill up there again if that was the issue.

 

It could possibly be cooked valves and the famous valve gunk ? Im not saying it is. Just a thought to maybe pick up boreascope and check them out.

 

done the valves last month lol and i use octane booster with each tank. think I'm just gonna drain it and refill. ill keep you guys updated

 

Using AC Delco plugs?

It fixes SES lights though

 

Don't drain and refill just stay out of boost and make your drive. Also adding octane boost on top of 91 can actually hinder performance due to adjusted burn rates.

 

lol. yes ac delco

 

i see a lot of knock if i don't use octane boost 91 is the highest grade fuel around here

 

Then update your tune

 

i have its just the poor quality gas here. even when i was completely stock i would see up to 16 degrees of knock on the rpd

 

That's a lot of knock. In my area the best I can get is 91 as well. And the highest I have ever saw with my gms1 is maybe 3 degrees. 4 maybe once or twice ever.

 

I got 91 around here to, saw some knock with shell non with co op, but we do have a husky with 94 in town, only one . Car only gets that . No knock

 

Its more likely the quality of the tune.
I bet money that other performance cars arent running around with those issues from the gas in your area....

 

I done a data log last week. Still waiting to hear from vince

 

Every gas station around does the same thing? I would try different stations they vary here so I would assume the same is true by you. And I would be in contact with Vince something isn't right, you need to log and update your tune

 

Why don't u guys go through the wot sight with ur data logs, iv done like 5 lately and I get response and updates the same day or the next day.

 

My next guess would be injectors.
Kind of a pain, but its logical. Your compression numbers seem descent.
Swap injectors around and see what happens.

 

just sent them one lol. the car will idle fine all day but when i drive around it misfires and goes back to normal for a bit and then misfires again almost sounds like a Subaru when its misfiring lol waiting to hear back from WOT tuning now

 

None of the symptoms you describe really scream bad gas.

Did you happen to over rev your car? Subaru sound is sometimes rockers/lash adjusters that have come off.

 

Car was set on cruise 60mph when it happened. I was also thinking about the lash adjusters but I figured if they popped off then it would sound like it all the time

 

had a retune done and still doing logs and the car still has the problem but only at low rpm. p0300 p0301 and p0304. wondering if its the injectors or the hpfp or electrical problem. car runs mint at idle and higher rpm

 

Ended up being bad gas and gummed up my fuel pump