question for ford techs - Pirate4x4.Com : 4x4 and Off-Road Forum

diefree · 09-21-2005, 12:35 PM

just can't figure it out. a good friend of myn has an 04 explorer with a v6.we just did a 2.5 " mandrel cat back with 50 series flowmaster and the k&n intake .he drives like a grandma and is losing 3mpg.the whole purpose was to gain mpg.the truck has stock size tires and no lift.can anyone please tell me why this is. every othe r vehicle seems to gain. thanx

ImNotRight · 09-21-2005, 03:23 PM

i've always been told flowmasters will kill your milage.

LeviGarrett76 · 09-21-2005, 04:13 PM

longshot, but un hook the battery for 30 mins wih the headlight swith on to reset the computer, then run a tank so it can relearn, then the next tank you should see better miles

yes flowmasters aren't exactly the master of flow, but they flow better than factory muffler

diefree · 09-21-2005, 10:37 PM

Quote:

Originally Posted by LeviGarrett76

longshot, but un hook the battery for 30 mins wih the headlight swith on to reset the computer, then run a tank so it can relearn, then the next tank you should see better miles

yes flowmasters aren't exactly the master of flow, but they flow better than factory muffler

why the headlight switch on?

mj · 09-22-2005, 06:05 AM

Ford factory mufflers are pretty free flowing
I bet they outflow a flowmaster

Jrod-13 · 09-22-2005, 07:33 AM

Yeah, I'd try putting a low restriction muffler on it if the computer reset doesn't do it

GubNi · 09-22-2005, 09:32 AM

Did you run duals or a single? Dual pipes would be too much.

diefree · 09-22-2005, 03:00 PM

Quote:

Originally Posted by GubNi

Did you run duals or a single? Dual pipes would be too much.

single

murrow68 · 09-22-2005, 03:42 PM

Could you really feel the diff after installing all that stuff or not? Go with a magnaflow if you want a muffler that flows better. Also you could put a glass pack in somwhere in the sys. We had a flow bench at the shop I used to work at and we tested diff mufflers for shits and giggles when it was slow one day and the glass back actually created a suction not a restriction. Oh and next to the napa muffler my friend had on his rig the flowmaster flowed the worst and I believe it was a 40 series. So I stay away from flowmaster if possible.

wetnsloppy4x · 09-22-2005, 04:09 PM

Quote:

Originally Posted by diefree

why the headlight switch on?

I'll take a stab at that one....

The ECM has capacitors which store electricity for a varying amount of time without battery power. The idea behind turning on the light switch is to make a draw in the electical system in order to discharge the capacitors. When it comes down to it, simply turning on the ignition with the battery disconnected does all the dirty work. This way, the ECM is attempting to switch on, dissapating all the stored power.

When you use this method it's really not neccessary to wait 30 min as the power in the ECM, thus the adaptive memory, is killed immediately.

If it were me, I'd kill the memory and then give it some time to relearn. OBDII ECMs are really sort of amazing with the capabilites they have.

Just in case you weren't aware, the proper way of letting the ECM learn initally goes like this:

1. Once memory is wiped, reconnect battery and start engine.
2. Let the engine idle (no A/C, no driver input) untill it comes completely up to operating temp. Usually about 15 minutes.
3. Once up to temp, turn on the A/C and let it idle for 5 more minutes. You're done.
If you wanna get tecnical there is also an inital "drive cycle" teqnique but I've never actually been able to tell the difference with or without.

diefree · 09-23-2005, 07:54 AM

Quote:

Originally Posted by wetnsloppy4x

I'll take a stab at that one....

The ECM has capacitors which store electricity for a varying amount of time without battery power. The idea behind turning on the light switch is to make a draw in the electical system in order to discharge the capacitors. When it comes down to it, simply turning on the ignition with the battery disconnected does all the dirty work. This way, the ECM is attempting to switch on, dissapating all the stored power.

When you use this method it's really not neccessary to wait 30 min as the power in the ECM, thus the adaptive memory, is killed immediately.

If it were me, I'd kill the memory and then give it some time to relearn. OBDII ECMs are really sort of amazing with the capabilites they have.

Just in case you weren't aware, the proper way of letting the ECM learn initally goes like this:

1. Once memory is wiped, reconnect battery and start engine.
2. Let the engine idle (no A/C, no driver input) untill it comes completely up to operating temp. Usually about 15 minutes.
3. Once up to temp, turn on the A/C and let it idle for 5 more minutes. You're done.
If you wanna get tecnical there is also an inital "drive cycle" teqnique but I've never actually been able to tell the difference with or without.

great info,thanx gonna give it a shot and see what happens.

09-21-2005, 12:35 PM	#1 (permalink)
diefree Registered User Join Date: Nov 2000 Member # 2337 Location: Folsom prison Posts: 620	question for ford techs just can't figure it out. a good friend of myn has an 04 explorer with a v6.we just did a 2.5 " mandrel cat back with 50 series flowmaster and the k&n intake .he drives like a grandma and is losing 3mpg.the whole purpose was to gain mpg.the truck has stock size tires and no lift.can anyone please tell me why this is. every othe r vehicle seems to gain. thanx __________________ If u have revolutionary potential u have a moral imperitave 2 make the world a better place.01GMC8.1

09-21-2005, 03:23 PM	#2 (permalink)
ImNotRight Registered User Join Date: May 2003 Member # 19666 Location: Napa, CA transplant. Posts: 1,207	i've always been told flowmasters will kill your milage. __________________ QUOTE=TheHawes;15027873 If it wasn't for pussy, I'd hunt them fucking things.

09-22-2005, 07:33 AM	#6 (permalink)
Jrod-13 Registered User Join Date: Feb 2003 Member # 17313 Location: Tower, MN Posts: 2,794	Yeah, I'd try putting a low restriction muffler on it if the computer reset doesn't do it __________________ A recent survay of over 1000 trailer parks in the southeast found the 350 chevy out numbered the mullet by nearly 4:1, draw your own conclusion.

09-22-2005, 09:32 AM	#7 (permalink)
GubNi Rock God Join Date: Jan 2004 Member # 25927 Location: Northeast TN Posts: 2,161	Did you run duals or a single? Dual pipes would be too much. __________________ Dana 60 or 14 bolt disk brake kits $315 shipped --> click here Dana 70 kits $300 --> click here . . Sterling 10.25 kits $390 --> click here Dana 60 front 3/4 ton kits $350--> click here

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09-21-2005, 04:13 PM	#3 (permalink)
LeviGarrett76 Registered User Join Date: Sep 2002 Member # 13654 Location: Ga Posts: 1,054	longshot, but un hook the battery for 30 mins wih the headlight swith on to reset the computer, then run a tank so it can relearn, then the next tank you should see better miles yes flowmasters aren't exactly the master of flow, but they flow better than factory muffler

09-22-2005, 06:05 AM	#5 (permalink)
mj Registered User Join Date: Oct 2000 Member # 1919 Location: BC Canada Posts: 7,547	Ford factory mufflers are pretty free flowing I bet they outflow a flowmaster

09-22-2005, 03:42 PM	#9 (permalink)
murrow68 Registered User Join Date: Aug 2005 Member # 51444 Location: Forest Grove, Or Posts: 42	Could you really feel the diff after installing all that stuff or not? Go with a magnaflow if you want a muffler that flows better. Also you could put a glass pack in somwhere in the sys. We had a flow bench at the shop I used to work at and we tested diff mufflers for shits and giggles when it was slow one day and the glass back actually created a suction not a restriction. Oh and next to the napa muffler my friend had on his rig the flowmaster flowed the worst and I believe it was a 40 series. So I stay away from flowmaster if possible.