Chrysler fuel mixture lean - how to fool the PCM?

Can anybody tell me _exactly_ how Chrysler PCMs determine 'fuel mixture lean' condition? I'm running Dodge Durango 99 on propane, and PCM consistently throws P0171 condition. Propane computer (Autronic) feeds emulated O2 sensor signal into vehicle PCM, and allows me to set emulation parameters: time low (0V) and time high (1V). I've tried reducing 'time low' to simulate richer mixture, but to no effect.

This has no effect on driveability btw... just would like to turn that damn Check Engine light off. It will always re-light after a couple of trips

Peter

Reply to
Peter
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Peter "Can anybody tell me _exactly_ how Chrysler PCMs determine 'fuel mixture lean' condition? I'm running Dodge Durango 99 on propane, and PCM consistently throws P0171 condition. Propane computer (Autronic) feeds emulated O2 sensor signal into vehicle PCM, and allows me to set emulation parameters: time low (0V) and time high (1V). I've tried reducing 'time low' to simulate richer mixture, but to no effect. This has no effect on driveability btw... just would like to turn that damn Check Engine light off. It will always re-light after a couple of trips."

Buy a performance chip and a programmer and custom program your vehicle.

Sarge

Reply to
Sarge

I have no answer, but I'd love to hear more about the propane conversion.

-rev

Reply to
The Reverend Natural Light

these are obd2 do you really need the newer type injection systems we have a fleet of hummer with the vortec in running great else you can try a lambda emulator like the aeb 426 obd fix

about £40

Reply to
lpg help line

I'd wonder why someone would even spend the money to do such a thing, I mean how many propane fill stations will fill that thing up?! Or have the correct fitting or whatever it takes to fill it. I guess if you have the kind of money to blow to do it than so be it I guess.

Reply to
Adam

In USA it really makes no sense. Europe is totally different matter - there is reasonable number of LPG filling stations, and it's almost 2x cheaper than gasoline

Google is your friend... try searching for 'LPG conversion'

Peter

Reply to
Peter

Reply to
Adam

Propane can be more efficient only in high-compression engines (octane rating is about 106, IIRC even more in US octane numbers). Regular gasoline engines consume 10-15% more LPG by volume.

Actually I remember reading somewhere you can get tax credit in US for driving alt fuel vehicle. There must be some strings attached, but maybe worth a try...

Peter

Reply to
Peter

On or around Fri, 9 Dec 2005 12:20:50 +0200, "Peter" enlightened us thusly:

except for Ireland, where it's about the same price as diesel.

Reply to
Austin Shackles

I know that a lot of people here use LP to heat homes, especially rual people in the country, its cheeper than electric, but the thing is you have to buy in in 200 gallon at a time to get it at a descent rate, I think its going for like 1.49 in my area right now. Last year it was 1.10/gal.

Reply to
Adam

That's not true at all. If 99% of the vehicle's operation is in its home town, it only takes one or two LPG stations to make it very practical. And its even more practical for a fleet operator who can economically invest in a fuelling station for the whole fleet.

Reply to
Steve

Please define the expression "2x cheaper" and/or write the mathematical equation for that statement. :)

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Reply to
Bill Putney

This type of expression drives me nuts, too... (though I think I know what it means.)

100% cheaper...

DAS

For direct contact replace nospam with schmetterling

Reply to
Dori A Schmetterling

simply 1/2 the cost/price

Reply to
Reggy

Reply to
philthy

for the fuel? what about economy (mpg)? a gal of propane (lpg) doesnt push a car as far as a gal of gas, does it? at lease in a vehicle that has been converted?

Reply to
Christopher Thompson

Then they ought to say that. '2x cheaper' is meaningless. If '2x cheaper' is 1/2 the cost, then (as I think Dori is getting at), '100% cheaper' must mean free - right? Or would '100% cheaper' mean 1/2 the cost because the one is twice the other. Then if that's the case, how can '2x cheaper' and '100% cheaper' both mean the same thing when 2x is twice what 100% is. Inverses confuse some people, therefore the sloppy language.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Reply to
Bill Putney

Exactly!! Unfortunately a lot of people don't seem to realise it is actually meaningless.

DAS

Reply to
Dori A Schmetterling

normally about 10% less , but the cost differential makes up for this and a years driving certainly recovers the install cost easily .

Reply to
Reggy

LPG price per liter = gasoline price per liter / 2

Satisfied now? ;)

Peter

Reply to
Peter

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