As anyone else noticed a drop in power from engines powered by fuel from a normal gas station, even Shell?

My truck (ProChargered water injected Chevy 6.0 LQ4)?is a lot less peppy in the past month or two. It is even effecting my wife's 4.2 I6 TrailBlazer. I add a mix of toluene, marine 2 stroke oil and MMT to get back to normal power from a few months ago.

Intake air temps are up but I have not seen anything above 106 in traffic. Normally it is OAT+10-15*F, so that makes it 85-90. If I go anyplace today it will be in the 100-115 range but I try to avoid the heat so I think I will stay in.

Did they do something to our fuel?

 

I've never had any issue with any gas station I've been too.

I've been able to run fuel from any of the pumps in my state without having any noticable performance issues or changes in how it acts. I can't say I pay much attention when I fuel up and have my tuner with me but when I have the ethanol content never varies more than 1-2% and the trims never seem to change ever.

Even when I had my supercharged grand prix, I could run 91, 92 or even BP 93 octane and not notice a change. Perhaps 91 octane could show more knock if the tune was setup to be more aggressive.

 

This is the first time I have noticed it this bad.
Would this happen with extra ethanol added and my tune not being E85 comparable?

 

I would say it's doubtful.

Every pump here in Minnesota can have up to 10% Ethanol and this is only my second vehicle with flex fuel. My old car and 06 sierra were not "made" to run ethanol fuels but it made zero difference with such low levels of E in the fuel.

Biggest things I always look at for lack of performance is tune up related things. Dirty air cleaners and dirty MAF sensors can cause a dip in performance. Ambient temps and how humid it is will have a big change in performance too.

 

There was a shift to lower vapor pressure fuel within the past few months, put that won't affect power output. Ethanol content will be displayed on the pump.

 

I get my power back when I add my fuel additive, toluene, 2 stroke oil and MMT. If I get Kroger fuel I know I I'll need extra additive. Shell or Valero usually does not take as much, but this fill up with Shell I don't have the power.

 

Is something pulling timming? Knock, IAT settings, low octane table...

The more u increase the octane level, the more resistance it has to burn. The only thing a lower octane fuel will do is cause knock which will pull timing and that will kill ur power. Could also be water getting into the fuel at the gas station. Try adding some methanol to ur fuel to absorb the water.

 

Timing is pulled by knock unless I add my fuel conditioner. Kroger and Speedway are the worse for knock issues for me. I use Shell but still get knock. I don't have a great deal of knock issues now that I have the Snow Performance water injection but I still add the conditioner to both my truck and my wife's I6 TrailBlazer we both use 93 octane.
To get more power from my water meth injection am I better to used more water in summer or do we stick with blue juice?

 

Tell more about your fuel blend additive :
Where you source MMT ?
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How much do you end up using, rough percentage if you will ?
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I have been using a common enamel reducer : premixed blend of
Acetone, Toluene, MEK, butyl ether, small dash of naptha, and less than 2 percent methanol.. About the same proportions as the Berrymans B-12 Injector cleaner, that is now impossible to find in gallons.
Use one gallon of that solvent blend, plus one gallon of 100LowLead avgas in a 250 gallon fill up with 90 Octane unleaded.
90 Octane is the highest level refined in state, mostly 87 in the bush, can find 90 only in the city.....
So far, the 1/2 percent AvGas has not hurt any O2 sensors.
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No good idea what my resultant Octane is with such mix, have to guess it nets me around 91 or 92.
Maybe a petroleum engineer will chime in and tell me how stupid I am.