Is this just another fuel economy myth???

[NuclearNed]

During my lunch break today I heard a clip from Paul Harvey. Yes, I know Mr. Harvey broadcasts some things that aren't exactly real, but this was interesting anyway.

DISCLAIMER: I'm not an auto guru, so I hope I'm relaying the story accurately.

He stated that for up to 9 MPG more, you should have your mechanic change your fuel system from "rich" to whatever the other option is. Then the timing has to be adjusted slightly, and you are good to go.

Apparently, a car's fuel system is set to "rich" during its break-in period (the 1st 5000 miles) because it makes the engine run a little cooler. After the break-in period, there is no reason to leave it on this setting.

Is there any truth to this?

 

[Kalvin00]

:roll:

I'm guessing he's referring to reprogramming the computer to run leaner.

It is already set to obtain a good balance between power and economy. There's no need to change it.

 

[radioouman]

I'm sure that his mechanic pulled this one on him and charged him a butt load and changed his air filter.

No truth to this. Maybe when we had carbs, but not today.

 

[iamwiz82]

Originally posted by: Kalvin00
:roll:

I'm guessing he's referring to reprogramming the computer to run more lean.

It is already set to obtain a good balance between power and economy. There's no need to change it.

Actually most FI cars run really rich.

 

[raptor13]

Stupid.

Any modern car with a fuel computer (at least within the last 10 years, if not longer) is continuously adjusting the mixture to achieve optimum efficiency depending on power and fuel requirement needs.


Things like this are just dumb. If it was really that easy to get 9mpg more out of a car, don't you think the auto makers would have done it by now?

EDIT: The same holds true for those stupid fans you install in your intake, magnets on your fuel lines, and other snake-oil products. If it was that simple and cheap, everyone would do it. Smarter people than you designed your car so what makes you think you're better at it? :roll:

 

[Eli]

Great, just what we need.

People frying their engines in the name of MPG.

 

[Reggae4k]

no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

 

[Kalvin00]

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

 

[hevnsnt]

Originally posted by: radioouman
I'm sure that his mechanic pulled this one on him and charged him a butt load and changed his air filter.

No truth to this. Maybe when we had carbs, but not today.

I think if you go into your mechanic's shop and tell them

"Please change my car to run rich, I want to increase my gas milage" they will put your picture on the wall as their most valued customer.

 

[stnicralisk]

If you run too lean you will damage your vehicle. Personally I wouldnt mess with it.

 

[NuclearNed]

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

I think he said something about this only working on fairly new cars.

 

[Reggae4k]

Originally posted by: raptor13
Stupid.

Any modern car with a fuel computer (at least within the last 10 years, if not longer) is continuously adjusting the mixture to achieve optimum efficiency depending on power and fuel requirement needs.


Things like this are just dumb. If it was really that easy to get 9mpg more out of a car, don't you think the auto makers would have done it by now?

it is not so stupid, you are just uninformed.

modern cars do run rich to protect the engine from running too lean which causes excessive heat. other factors are involved as well but if you do retard the timing correctly, you can achieve more hp and mpg.

 

[Eli]

Originally posted by: raptor13
Stupid.

Any modern car with a fuel computer (at least within the last 10 years, if not longer) is continuously adjusting the mixture to achieve optimum efficiency depending on power and fuel requirement needs.


Things like this are just dumb. If it was really that easy to get 9mpg more out of a car, don't you think the auto makers would have done it by now?

Exactly, although it's a little more complicated than that.

To an automaker, the question is .. "Is it reliable?".

They probably could get another 9MPG out of the engine somehow, but if it isn't going to be reliable (or desirable), it doesen't matter.

Same basic principle between building an engine up.

A well built engine developing 150HP will last say, 250,00 miles.

The same engine is perfectly capable of developing 300HP. But it won't last 250,000 miles anymore.

 

[The Stigenator]

i rather not have a hole in my piston and bore by running lean. Plus lean running puts additional pressure on teh coolant cause now you are running hotter than before.

Frankly i rather just cough up the additional penny and save the engine.. American greed is boundless.

 

[Reggae4k]

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

 

[Kalvin00]

Originally posted by: Reggae4k

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

Oh man..

 

[iamwiz82]

Originally posted by: Reggae4k

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

Actually no...

 

[Eli]

Originally posted by: Reggae4k

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

pssst...

Most modern cars have an ignition coil per spark plug, rather than a single ignition coil and a distributor.

 

[gsellis]

With gasoline, the difference between lean and rich would not be 9mpg (not too much room to play with the fuel/air mixture before it quits burning.) If you were running methanol or ethanol, maybe. But as posted, if it were carborated and no electronics controlling fuel flow, mixture, spark, etc. only.

 

[sonoma1993]

alot of newer cars/truck these days dont even have a distributor. When id had my 90 pontiac 6000 with the 3.1L v6. it had a distributorless igintion system. It had 3 coil packs. 1 coil pack for 2 clyinders. My uncle truck has this coil on sparkplug igintion system setup.

 

[Vic]

Originally posted by: Reggae4k

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

Modern cars have multi-coil distributorless ignition systems aka "coilpacks". The engine computer controls and automatically adjusts all ignition timing on the fly.

AFAIK, tampering with the ECU to run at an overly lean setting will violate your manufacturers warranty (for a number of very valid reasons, too lean will cause pre-ignition knock, and knock can cause major engine damage). Mr. Harvey needs to be more careful with the BS he spews.

 

[ATLien247]

Why would you take advice from Paul Harvey?

(Apologies in advance for RealPlayer )

 

[spidey07]

Originally posted by: ATLien247
Why would you take advice from Paul Harvey?

(Apologies in advance for RealPlayer )

Really.

This is the guy who expounds and praises the Bose radio.

There should be zero credibility with anything he says, ever.

 

[DingDingDao]

Originally posted by: Reggae4k

Originally posted by: Kalvin00

Originally posted by: Reggae4k
no, it is not reprogramming the computer to run more lean, it is adjusting the distributor to retard the timing.

And which cars today have distributors?

what do you think your spark plug wires are connected to? a magic box called a DISTRIBUTOR!

Welcome to the new millenium, my friend. We also have done away with the carburetor and invented this new contraption called the airbag.