Help! Very low mpg –wrong PCM?
Posting Guru
Joined: Nov 2005
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From: La Grande, OR
when the larger tires are on your truck, they travel farther in each spin than shorter ones do, throwing your speedometer off. With larger tires, it will make your speedometer read slow, however, the difference b/t 265/75 and 275/60 is so small that it doesnt matter, but if you went from a 28" tire to a 35" tire, it would throw the readings way off.
I don't know about the exhaust, but I have heard a lot of things about that, so I think thats how it goes.
You said you checked gear ratio on the door panel, what ratio do you have? Are you sure that OD is working? How many RPMs are you running at cruising speed?
I don't know about the exhaust, but I have heard a lot of things about that, so I think thats how it goes.
You said you checked gear ratio on the door panel, what ratio do you have? Are you sure that OD is working? How many RPMs are you running at cruising speed?
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Freshman User
Joined: Feb 2007
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From: northern Germany
I calculate the difference of the rollupway from both tires - it is onli 8% that means if the odometer tells me 100 miles i was only driven 92 miles. on other words: only 8% increase of fuel. for my understanding the PCM is only a computer who calculates different inputs for optimized outputs. After I see how the specialists have tinkered and how they do that, maybe the PCM are complet reprogramed! Is that possible?
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Freshman User
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From: northern Germany
Sorry I forget the to answer your question;
the od wors finne - if I) drive normal the gears will change betwin 1700 and 2000rpm, that meas betwin 41 an 43miles the od get in.
the od wors finne - if I) drive normal the gears will change betwin 1700 and 2000rpm, that meas betwin 41 an 43miles the od get in.
Posting Guru
Joined: Nov 2005
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From: La Grande, OR
yeah everything is working right with the trans it sounds like. I didn't think that the tire size, being that close, would make much of a difference. I don't know if you can get yours reprogrammed, but you can get a new one, if you have a Ford Dealership somewhere near you, go there. THe price will be pretty hefty though, for a new PCM when I was looking for one, it was $350 U.S. At 2000RPM you should get a lot better than 6mpg. I get 16 with my 351W.
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Freshman User
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From: northern Germany
Yea, it is easy in US go to a ford dealer and by a new one - but I sitting in germany! Here are a öot of Ford dealers but nobody has knowledge about US-Cars because Ford never official imported Trucks or Vans from US. The smal Group of Ford Trucks runnig in Germany are mostly from the Army ore self imported with all the Problems with the German Law / TUEV. Only GM has importet official US-Cars and trucks. It is very mutch easier to order spareparts for GM-Cars and find a specialist the for Ford.
The only way is to order in US direct and then you must find somebody who are willing to ship that as "gift" to germany!
That what you saying is a drem for me: 16mpg! But that is what I heard about before I bought this car. I find a lot of PCM#s in ebay but nothing with F5TF-yB and the Dealer who offer a new/rebuild one for 299$ are not willing to ship to germany
The only way is to order in US direct and then you must find somebody who are willing to ship that as "gift" to germany!
That what you saying is a drem for me: 16mpg! But that is what I heard about before I bought this car. I find a lot of PCM#s in ebay but nothing with F5TF-yB and the Dealer who offer a new/rebuild one for 299$ are not willing to ship to germany
Posting Guru
Joined: Nov 2005
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From: La Grande, OR
being an F150 (w/8.8") and having a E4OD (w/.67 OD ratio) and running 2000RPMs at cruising speed (im guessing 60 b/c he didnt say) he should have a 3.55 gear ratio. That's what mine is and about what I run with mine, I'm using it as a comparison.
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Freshman User
Joined: Feb 2007
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From: northern Germany
on the certification label the axle code is H9, that should be an ratio of 3.55 LS my manual says.
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Freshman User
Joined: Feb 2007
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From: northern Germany
today i get out in my paddoc with 4x4 and puch the gas for more power and then then engine starts to stutter and sounds licke to mutch fuel get in! I think the ECU/PCM is wrong.
I find one at nordstroem for a E150/F250 with E4OD with F5TF-PB. Is sombody there who can tell me the difference betwin F5TF-yb and F5TF-PB? Ore is an other Type of CPU campatible? Maybe F4TF-xx or F6TFxxx?
I find one at nordstroem for a E150/F250 with E4OD with F5TF-PB. Is sombody there who can tell me the difference betwin F5TF-yb and F5TF-PB? Ore is an other Type of CPU campatible? Maybe F4TF-xx or F6TFxxx?
Fleet Owner
Joined: Aug 2005
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From: Easton,Ks
Originally Posted by nobleboy
today i get out in my paddoc with 4x4 and puch the gas for more power and then then engine starts to stutter and sounds licke to mutch fuel get in! I think the ECU/PCM is wrong.
I find one at nordstroem for a E150/F250 with E4OD with F5TF-PB. Is sombody there who can tell me the difference betwin F5TF-yb and F5TF-PB? Ore is an other Type of CPU campatible? Maybe F4TF-xx or F6TFxxx?
I find one at nordstroem for a E150/F250 with E4OD with F5TF-PB. Is sombody there who can tell me the difference betwin F5TF-yb and F5TF-PB? Ore is an other Type of CPU campatible? Maybe F4TF-xx or F6TFxxx?
What you need is the program code not the part number unless you are going to Ford for the part.
There are a lot of part numbers with the same program in them and all you need is one that has that program in it.
If you do not know what a program code is go to this link below and then post your program code.
http://fordfuelinjection.com/?p=17
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Freshman User
Joined: Feb 2007
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From: northern Germany
Thanks for the information and the link. I check tje code number and on my PCM/ECU is "JOC1". on the side you send me this code is for "5.8l Bronco, F-x50,E-x50 - SD-RAM" what ever this means. Mayby is this ECU not the original for this truck?
I reset all the codes how described in the service manual and the milage do I mess with the gas I fill in. So it runs with 11.6l (about 3 gal) 18.1mile.
I reset all the codes how described in the service manual and the milage do I mess with the gas I fill in. So it runs with 11.6l (about 3 gal) 18.1mile.
Lead Driver
Joined: Feb 2003
Posts: 8,140
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From: Oak Harbor, OH
The exhaust in normal, yes it does go from a 3" pipe to a 2 1/4 inch pipe.. Stupid I know. It sounds like you may have a weak fuel pump or a clogged filter. That or the ignition module didn't advance the timing correctly. If it's a '95 then there should be two wires on the drivers side inner fender. It will have a spot in where a jumper should go. If that jumper is missing then the computer (ICM) can't adjust the timing according to the throttle pressure. It will cause those symptoms.
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Freshman User
Joined: Feb 2007
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From: northern Germany
If it's a '95 then there should be two wires on the drivers side inner fender. It will have a spot in where a jumper should go. If that jumper is missing then the computer (ICM) can't adjust the timing according to the throttle pressure. It will cause those symptoms. I found 2 wires from the ignition Module with the Spout bridge and two longer drilled wires with a black connector, closed with a black cap - no bridge. Maybe you can say me the number of the wire that i can find it in the electrical service manual.
Lead Driver
Joined: Feb 2003
Posts: 8,140
Likes: 4
From: Oak Harbor, OH
The SPOUT is the one you're looking for. Unplug the jumper from it with the engine running and the idle should change. If it doesn't you may have a break in the wire between the ICM and the distributor.