Loss power after gas fill up HELP!

[rs_two_five]

Originally Posted by Lonewolf

Heat and humidity can do a number on performance...

X2

Or possibly the feeling you're getting is from the added weight of the fuel in the tank. Heck, I notice driving my WRX when the tank is low vs full. It's the reason why I always fuel up before auto-xing.

[CircuitJerk]

There could be several things at play here.
Fueling up with a reduced octane level can cause the ECU to start correcting and changing timing to compensate. I don't know how the 86 is set up so this part is more speculation than anything.
I've had it take almost half a tank or better before things settle in. My Rav4 V6 shares the same engine as one of the Lexus models with direct injection that requires premium. It is rumored the ECU programming is identical and has the logic to compensate for regular or premium.
When I changed to 93, after about 3/4 tank I noticed more pull and responsiveness especially in hot humid weather. The mileage improved slightly as well. When fall came and the temps dropped to the high 70's (F) I changed back to regular and had a similar experience for what it seemed like an entire tank of fuel.
What I suppose was happening was the higher octane in the higher temps and humidity allowed more aggressive timing and better performance whereas the 87 it would just lag in hot weather since it was pulling timing..

Don't panic, drive it out but avoid WOT as much as possible.
Go back to the 93+ and give it a half tank and see what happens.

[Grimlock]

Originally Posted by Ad8707

Filled 91 v power (no ethanol), hour later noticed significant power loss..it's taking awhile for the rpms to climb...car has 4000km no oil change..did I get bad gas...or is something more serious ie maf sensor fuel pump/fuel filter..it takes awhile for those things to go bad right...

Update? It's been over a month.

[Razz]

When this happens buy a can of HEET to remove water.

http://www.autozone.com/autozone/acc...ier=136367_0_0_

[Coheed]

Use ISOHEET it is non-corrosive.

[TemeCal]

Originally Posted by Ad8707

Filled 91 v power (no ethanol), hour later noticed significant power loss..it's taking awhile for the rpms to climb...car has 4000km no oil change..did I get bad gas...or is something more serious ie maf sensor fuel pump/fuel filter..it takes awhile for those things to go bad right...

Sorry to resurrect this thread. However, I just had the exact same thing happen to my car. My car had Mobil 91 in it, and it was very quick and responsive. Just fueled up with 91 Shell V-Power, and it is SLOW now. It honestly feels like a completely different car, like I'm back in the Corolla rental Toyota put me in.

Anyway, I was curious to see if you resolved your issue. If so, what'd you do? Switch brands? Octane booster?

Before anyone says I should be using 93, I'm in CA and only have access to 91. I do have some Torco fuel additive I use in my desert toys, so I may mix some into this tank.

Thoughts??

[so26]

Originally Posted by Ad8707

Filled 91 v power (no ethanol), hour later noticed significant power loss..it's taking awhile for the rpms to climb...car has 4000km no oil change..did I get bad gas...or is something more serious ie maf sensor fuel pump/fuel filter..it takes awhile for those things to go bad right...

Soooo how does this story end?

[Rob_g]

Originally Posted by TemeCal

Sorry to resurrect this thread. However, I just had the exact same thing happen to my car. My car had Mobil 91 in it, and it was very quick and responsive. Just fueled up with 91 Shell V-Power, and it is SLOW now. It honestly feels like a completely different car, like I'm back in the Corolla rental Toyota put me in.

Anyway, I was curious to see if you resolved your issue. If so, what'd you do? Switch brands? Octane booster?

Before anyone says I should be using 93, I'm in CA and only have access to 91. I do have some Torco fuel additive I use in my desert toys, so I may mix some into this tank.

Thoughts??

I have tried v-power 91 octane and it seems to consistently lower the mileage I get by about five to ten percent. We don't have 93 anywhere locally here in SK.

Rob

[TemeCal]

Originally Posted by Rob_g

I have tried v-power 91 octane and it seems to consistently lower the mileage I get by about five to ten percent. We don't have 93 anywhere locally here in SK.

Rob

Thanks Rob. Did you notice any loss in power also? This is my 1st tank on Shell, and happens to coincide with my power drop.

[gmookher]

shell sucks?

[Razz]

Gas Stations vary in the amount of ethanol from day to day.

This effects power output.

[gmookher]

Originally Posted by gmookher

shell sucks?

No , not to be g=funny, i live by techron/chevron, but have been using shell in the BRZ for a quieter fuel pump, but I too feel there is less power in Shells 91 vs the other guys 91

[SMOKETREES]

I use shell at least once a month just to clean up things inside but i do see a difference using shell compared to QuikTrip gas..... Use that all the time and it seems to have more go compared to Shell

[AVOturboworld]

The problem with gas stations, especially ones that you have never been to before, is that while you paid for, and thought you pumped, 91+ octane gas into your car, you are unfortunately at the mercy of the gas station owner, who may not actually be using 91+ octane at those pumps. In Japan there was a big scandal over that, actually.

It's something we noticed on our big cross-country road tune trips. Most gas stations were "honest", but occasionally we'd hit that bad one and the car would would start pinging.

[Bristecom]

I'm pretty sure I got some bad V-Power my last fill in the Eclipse. I'm still trying to work it out of the system. There's been rumors of bad gas going around (no, not that kind of gas) also with BP. But I've been using V-Power for years and this is the first time I may have had an issue (but I'm still not 100% certain it is the fuel).

[Rob_g]

Originally Posted by TemeCal

Thanks Rob. Did you notice any loss in power also? This is my 1st tank on Shell, and happens to coincide with my power drop.

I couldn't say, but it sure as heck didn't run any better with it.

Rob

[FRiSson]

Got something like this a while back. I thought my calipers were dragging - but that wasn't it. The engine would lose power, particularly at neutral throttle, and I had to goose the accelerator to compensate. It continued to act up periodically through about 4 fillups. Finally, it has disappeared after 1,000 miles. I took it to two dealers, but the problem is kind of subtle and they just couldn't feel it. Gas mileage suffered by about 10% as well.

[jasper]

Originally Posted by Ad8707

Filled 91 v power (no ethanol), hour later noticed significant power loss..it's taking awhile for the rpms to climb...car has 4000km no oil change..did I get bad gas...or is something more serious ie maf sensor fuel pump/fuel filter..it takes awhile for those things to go bad right...

I drove my car a lot before getting the crickets fixed I had this issue my dealership said it was because the fuel pump was bad which caused the crickets once I got them fixed that all went away. Not sure how true all that is but it seemed to work.

[TemeCal]

So, I happen to have 5gal of Torco Accelerator in my garage. I added 8oz of it to my ~10gal of fuel. My car woke up BIG time.

I'm not sure what the issue was, but it was either bad gas or lower than the advertised 91 octane. My car is running great again! No more Shell for me (may try it again later).

[captainzib]

Originally Posted by RandomHero

Not to be a stick in the mud but doesnt each bottle raise the octane by like 0.3? so to go from 87-90 thats 30 bottles? Octane doesnt make power it just prevents knock. Look elsewhere before wasting money on octane booster. Take it to dealer if it gets real bad. But unless its knocking (banging) the octane is fine.

I realize this is an old thread, but I just thought I'd point out that while the bit in bold is correct, when modern cars sense lower octane than desired, the computer will adjust the timing to compensate which could result in the power loss OP is feeling.

It says in the manual for this car that 93 is preferred but 91 can be used if that's not available. I know there are cars out there that say 93 preferred but 87 can be used, with the ecu running different timing as mentioned above to compensate.

[Gixxersixxerman]

Originally Posted by captainzib

I realize this is an old thread, but I just thought I'd point out that while the bit in bold is correct, when modern cars sense lower octane than desired, the computer will adjust the timing to compensate which could result in the power loss OP is feeling.

It says in the manual for this car that 93 is preferred but 91 can be used if that's not available. I know there are cars out there that say 93 preferred but 87 can be used, with the ecu running different timing as mentioned above to compensate.

Our cars will run on 87 if you have to put it in.. I've been out of the mechanic field for a few years.. But when I was doing my ASE classes and schools and stuff.. There wasn't a car that is a USDM vehicle that couldn't run on 87.. They all had to have a map.. Even Ferrari or Lamborghini ... They couldn't be responsible for a engine that blew out of warranty because all that is around is 87 octane and the driver had to use it.. For instance the sandy incident, 87 was all that was available in some places.. If you had to put it in your car and the engine would detonate, even with that sticker, the manufacture is still responsible, it would be a law suit they wouldn't want to handle.. It'll run different.. You especially notice it in the summer months.. But it should still run acceptable.. I thought about running 87 for half a tank to see the differences in this car.. My 93 probe with the Jdm KLZE engine was suppose to run 93+ but ran just fine with no noticeable difference in performance.. Unless i was driving up the only hill in central Texas.. Then I could hear a slight knock.. Other wise fuel mileage and performance stayed the same.. I remember when I used to cry over 1.75$ for premium.. We have a station here in Barstow off the highway to get the suckers that don't turn left and drive a block that pay 4.35 to 4.80 for 91.. It's like 3.75 a block down the road the other way..

[FRiSson]

I have had problems after two fillups. The first one lasted for about 1,000 miles. After the second time it happened, I added a half bottle of HEET additive. It went away quickly after that. I believe that the FR-Z is particularly sensitive to gas quality problems due to the dual nature of the fueling system.