Thoughts on Fuse pull

[JohnnyBfromPeoria]

Originally Posted by WheelmanSS

There is no such thing as a "butt-dyno".

Is too. Just had mine calibrated.

John B.

[RollaMo]

Originally Posted by WheelmanSS

There is no such thing as a "butt-dyno".

More "butt-dyno" talk on this forum than any other I belong too.

[atma]

Originally Posted by Comrando

Maybe ounces.

Take the hose off the pump without activating the pump. Aim it at a measuring cup and squeeze the handle.

incorrect. this is the amount that will come out when the dispenser is not activated b/c it's designed not to let you pump fuel without paying. however, if you were the remove the nozzle and it empty it as well as the hose into a bucket, you would get somewhere around 1/4 of a gallon (i'm just estimating, never actually measured it). I work on this kind of stuff all the time, so yeah, you're gonna get a li'l bit of Regular mixed in with your Premium if the person before you pumped Regular. The way to avoid this is to find a station that has a separate hose and nozzle for each product grade. Then the only thing that's ever been pumped through that hanging hardware is the product you're purchasing.

[slick rick]

People are still debating this when there's an official bulletin from GM about it?

#PIP4728: Higher Than Expected 0-60 MPH (97 KPH) Acceleration Time- (Nov 4, 2009)

[WheelmanSS]

Originally Posted by slick rick

People are still debating this when there's an official bulletin from GM about it?

#PIP4728: Higher Than Expected 0-60 MPH (97 KPH) Acceleration Time- (Nov 4, 2009)

Ok, let's take a look at this "bulletin"

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Some customers may complain of higher than expected 0-60 MPH (97 KPH) acceleration times when hot ambient temperatures are present. In some cases, they may report 0-60 times around 7 seconds.

This may be the result of the vehicle being filled with regular grade unleaded gasoline at one time. If the vehicle has been filled with regular unleaded gasoline, the ECM may be compensating for the lower octane by retarding the ignition timing during certain driving conditions

Recommendation/Instructions:
If SI diagnosis does not isolate the cause of this concern, perform the suggestions below if the customer wants the best performance from their Camaro:

•In an area where it is legal to do so, take a snapshot of a 0-60 WOT acceleration event and compare the vehicle speed parameter to the snapshot timer to determine the 0-60 MPH time.
•Determine what gasoline octane the customer has been filling the vehicle with.
• 2a. If they have never used anything but premium unleaded with a posted octane of 93 or higher, go to step 3.

• 2b. If they occasionally use regular or mid-grade gasoline, the gasoline must be removed from the tank and it must be refilled with fuel of 93 octane or greater. This can be done by advising the customer to switch to premium fuel of 93 octane or greater and returning after a few tanks of premium fuel have been consumed. Or, if immediate results are necessary, drain the fuel tank, refill it with premium fuel of 93 octane or greater, and drive the vehicle at least 15 miles to purge the old fuel out of the fuel lines.

•Reprogram the ECM with the latest TIS2Web calibrations to reset the ECM adapts. Normally this reset can also be accomplished by pulling the 2 main ECM fuses (F13R and F20U) shown in the ECM Power, Ground, MIL, and Serial Data Schematic (SI Document # 2209065).
•In an area where it is legal to do so, take another snapshot of a 0-60 WOT acceleration event and compare it to the original snapshot to determine if the 0-60 MPH time has increased. If an increase is noted, advise the customer that they should only use premium unleaded gasoline with a posted octane rating of 93 or higher to continue getting the best performance from their Camaro. This is outlined on page 8-45 of the owner's manual. GM Connect Message G_0000037144 was also sent out on 9/2/2009 about filling stock units with premium gasoline. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

The whole bulletin is mere quick trouble-shooting details for technicians doing due diligence. The computer of a vehicle is and always should be learning and adapting. If this was a wide spread, sure-thing that happened whenever someone filled up with a different grade of gas, they would have made necessary and permanent changes to the default fuel tables.

[rberns]

All that matters WheelmanSS, is the fuse pull has worked for so many of us here on this site. Just because it doesn't work for you doesn't mean the fuse pull is a make believe miracle to getting our sluggish cars performing where they should be after lower octane levels have been replaced by higher octane. This topic is very debateable, but if so many people are noticing a difference then one would incur that this fuse pull is doing something. Even in the thread of fuse pull, one of the guys on this site to GM and they themselves had talked about technicians reflashing the system to relearn a higher octane, or incase what we did save our own money and pull 2 fuses and get the same effect.

[WheelmanSS]

Fair enough. All I'm saying is that it is not a sure-thing. I don't want people to get a false hope.

My car had some miles on it when I bought it. The dealer admittedly said they had put regular gas in. I wasn't impressed with the stock performance with my car. I had a feeling this "fuse pull" thing wouldn't make a difference knowing how a car's computer worked. And sure enough, I was right. There was no significant change after I tried said fuse pull.

Just saying.

[Birm]

Originally Posted by WheelmanSS

Fair enough. All I'm saying is that it is not a sure-thing. I don't want people to get a false hope.

My car had some miles on it when I bought it. The dealer admittedly said they had put regular gas in. I wasn't impressed with the stock performance with my car. I had a feeling this "fuse pull" thing wouldn't make a difference knowing how a car's computer worked. And sure enough, I was right. There was no significant change after I tried said fuse pull.

Just saying.

I concur. Never worked for me, not saying it doesnt, just saw no difference on mine.

[slick rick]

Originally Posted by Birm

I concur. Never worked for me, not saying it doesnt, just saw no difference on mine.

Curious...

are you saying you (or someone else) put 87 octane in your tank and you didn't notice a degrade in performance?

And then you ran a few tanks of 91 or 93 and did the fuse pull and didn't notice any improvement in performance?

[SPCBA]

I am not sure all cars get stuck on the lower octane table, or if it is even an issue with current model year. I can tell you my 2010 bought in summer 09 did get stuck, the dealer put 87 in it. When I first started reading this forum I saw a thread about it. I did the fuse pull plus battery and it changed my car drastically.

[BlueRay-J]

Originally Posted by atma

incorrect. this is the amount that will come out when the dispenser is not activated b/c it's designed not to let you pump fuel without paying. however, if you were the remove the nozzle and it empty it as well as the hose into a bucket, you would get somewhere around 1/4 of a gallon (i'm just estimating, never actually measured it). I work on this kind of stuff all the time, so yeah, you're gonna get a li'l bit of Regular mixed in with your Premium if the person before you pumped Regular. The way to avoid this is to find a station that has a separate hose and nozzle for each product grade. Then the only thing that's ever been pumped through that hanging hardware is the product you're purchasing.

There is almost a full gallon in the hose. I managed 2 amaco stations 15 yrs ago. After replacing the hose, I would have to fill it so the customer didn't get charged for that gallon. I was surprised that it took about .94 gallons.

Edit- I did more research and perhaps I've remembered incorrectly. Most Internet info points to about a third of a gallon in the hose . Either my memory fails me, or perhaps they are only considering the hose, and there is additional plumbing in the pump that holds fuel for the line. Each grade had its own hose back then, so you at least received 100 % of the grade you paid for.
Sent from my DROID RAZR using Tapatalk 2

[rberns]

Originally Posted by BlueRay-J

There is almost a full gallon in the hose. I managed 2 amaco stations 15 yrs ago. After replacing the hose, I would have to fill it so the customer didn't get charged for that gallon. I was surprised that it took about .94 gallons.

Sent from my DROID RAZR using Tapatalk 2

Very interesting. Never thought about this before. Luckily, I believe the station I go to has a separate line for the premium fuel.

[tonyko1]

Originally Posted by Hercules

What fuse numbers do you pull for this?

Any, it really doesn't matter.

[mattsfirstSS]

guess i better never pump only one gallon of "93" into the camaro or I may only be running 87 octane. Better pump at least 2 gallons huh so i get 90?