Running Rich!!

[Mavs41]

So, a couple a days ago I was doing about 120mph WOT on the Highway.,The engine light flashed so I let go of the gas and the light went away. The car started running normal but the air/fuel ratio was at 14:0 when usually it was at 14:7 cruising speed or idle.. I was concerned so I went back to stock tune from the unleashed tune. The next day I hit 100 mph no WOT but then stopped at a red light and it began knocking vibrating. I changed the spark plugs but still ran the same. I even tried WOT runs hitting 120 ish after wards but with no knocking.I have taken it to 2 dealers and both have said it runs fine. I just feel that something is wrong and wanted to get your guys opinions of what it could be.

Sponsored

 

[OVRKILL]

What was the code?

 

[Mavs41]

What was the code?

I tried reading it but nothing showed up, I feel like putting the unleashed tune back and see if I can replicate it, but It feels really risky.

 

[Juben]

If the CEL was flashing, that's usually an indication of a bad misfire or something that has potential to cause severe damage if it isn't fixed. Perhaps you have a bad tank of gas or something. What did the old plugs look like?

 

[PewterCam]

14.0- 14.1 afr is standard for modern fuels that have 10% ethanol mixed in. My car is always around that range. 14.7 afr is only for pure gasoline.

 

[Mavs41]

14.0- 14.1 afr is standard for modern fuels that have 10% ethanol mixed in. My car is always around that range. 14.7 afr is only for pure gasoline.

The spark plugs look like normal wear, but what keeps bugging me is the air/fuel ratio. It use to idle at 14:7 and now it idles at 14:0 and the Cylinder head temps run hotter than usual. They hit 200-220 on just normal highway driving.

 

[Juben]

The stoich point of E10 93 is 14.08, so that'd be a normal AFR if you're running gas with 10% ethanol, like PewterCam mentioned. The ECU can adjust up to an E15 blend, so as long as it's staying around 14.1-14.7, I think you're fine. The coolant temp going up a bit could be due to the active grille shutters (AGS) closing at higher speeds to help with aerodynamic efficiency. That affect would be compounded throughout the year as the ambient temperature outside starts to increase over the summer months.

 

[ypena02]

My car is not tuned and the afr is always 14.0- 14.1 while cruising/idle. This is on 93, all the gas stations in my area are 10% Ethanol.

 

[Mavs41]

I might just be over reacting then, but I'll keep a look out for anything

 

[Mavs41]

I just began to notice this weird flutter sound that I never heard before, wanted to know what you guys think.

 

[AhmadAq]

Hello @Mavs41,

did you figured out what was the problem ? and did you fixed it ?

regards,

 

[TeeLew]

When in doubt, put in a set of new, gapped plugs. Don't just look at them. Change them.

 

[Coyote Chase]

When in doubt, put in a set of new, gapped plugs. Don't just look at them. Change them.

Just wondering where most guys gap thier plugs? I gap my 91/93 octane plugs at .028, my pump ethanol plugs .024 and my canned ethanol (VP X85) at .026
I didn't use any scientific calculations to come up with these sittings. Just recommendations and past experiences. But, I haven't had any issues and my data logs look OK... Still just a shot in the dark!

 

[TeeLew]

Just wondering where most guys gap thier plugs? I gap my 91/93 octane plugs at .028, my pump ethanol plugs .024 and my canned ethanol (VP X85) at .026
I didn't use any scientific calculations to come up with these sittings. Just recommendations and past experiences. But, I haven't had any issues and my data logs look OK... Still just a shot in the dark!

I think the numbers have been figured out by mortar fire as much as anything, but most tuners and builders like that 0.026-0.028" range with Iridium plugs.

Sponsored