mpg keeps getting worse after fuel efficiency mods??HELP!!

[FORDF250HDXLT]

agreed.probably just forgot to hold WOT during the scan,like is required for the idi.
also agreed,the TPS is out of range anyway,code or not lol,and also agreed it should be replaced every 50k miles and to add:
OR whenever a new/rebuilt trans is installed.

disagreed about old tps/fipl values however.no offense to anyone.
set idle properly first,then tps to 1.2V idle and 4.5V WOT.-anything else is outdated info and has been updated/revised in technical bulletin #186a (and specifically states old values were incorrect,and one should remove them from their records) back in 1994.

those with the E40D trans should read the revised bulletin #186A carefully.
it's kind of a shame really the old one wasn't deleted from the tech articles here,as it clearly states 186 was incorrect.
#186 dated 1992 id guess is post #1 here:
http://www.oilburners.net/forums/showthread.php?4134-Whats-a-FIPL&p=316675&viewfull=1#post316675

post #2 being the revised bulletin #186A that says to remove #186 from your records.
it's very important to follow the second post there,instead of the first one,as you can clearly see if you read post #2 (186A) thoroughly.your multi thousand dollar trans depends on you doing so.

 

[sms8921]

Well I am still getting terrible fuel milage. I cant seem to figure out why. I cracked all my injectors and every one affects the idle. If anyone has any tips to offer thanks! To make it worse I had to drive the grooms cummings last night in the wedding I was in and its pretty built its an 01 with a 6 speed and pushing 42lbs of boost. I got back in my truck and felt like it had a four cylinder under the hood...lol

 

[sms8921]

I was gonna get a pyro and try and turn the pump up would that help with power. I wish I knew someone close that could drive it and tell me if its normal on power or low that knows these trucks. I dont think I could hook up to 10,000lbs and pull it. My 3000lbs I pull feels real heavy.

 

[riotwarrior]

Just curious...HOW many miles on this truck?

Have you done a compression test?

Still based on the fact your IP and injectors appear original, it's a combined old age/worn IP and injectors.

A fresh set of BB's and a Moose or quality remaned pump along with PROPER timing should wake your rig right up.

 

[FORDF250HDXLT]

yeah.the first thing you do to a gas engine when economy is down is a complete tune up right?
the same needs to be done with the diesel.these are all mechanical and have ip and injectors that a medium ware items,unlike the newer DI diesels where you have a fuel system designed to last as long as the engine and a computer to adjust timing and fuel.
that's the disadvantage we have for being all mechanical,we need to tune things periodically manually.ip and injectors every 100k.properly keeping fuel adjusted as the ip wares,and setting timing whenever the fuel screw is adjusted or at least every 30k miles for good measure.
diesels cost more to maintain properly than gas engines but when you do,economy is better offsetting the cost compared to the 460 gas hog option of the era for approx same power level.
3k lbs should NOT slow your truck down.i'm 8k lbs empty,and my old gal can scoot right up to 80 if i push her.and it doesn't take long to do so either.that's with a big enclosed wind catching dump bed.you should be able to blow mine out of the water with just a light pickup bed.
like riotwarrior and others have said back along,if you don't verify compression if she's got a little age,and do a complete tuneup,you'll fail before you even start when it comes to economy increases.
of course don't forget the basics either.making sure t-case and axles have fresh synthetic,no sticking brakes,and wheel bearings are all good.no failed engine accessories such as a failed in the lock state engine cooling fan,or seized up vac pump/ac compressor,failing bearings in alt.etc.etc.etc.

for starters you'll need to dig into the wallet and spend a good 1k just for tuneup and tools.
ip
injectors
ferret timing adapter
timing light w/advance
if you don't plan on these things,perhaps a gas engine truck would better suite ones needs.
diesels,even the old idi's are not cheap to "properly" run.they're just more affordable than some other options is all.

 

[sms8921]

ok I checked the temps on the cylinders. 5 are at 119-120 degrees and 3 are at 89-91 degrees. I am thinking I have at least three bad injectors?

 

[sms8921]

Well I think I am gonna get new IP and injectors soon. I also am going to buy a timing light and feret adapter. Is there a specific timing light I need that will work with the feret adapter?

 

['94IDITurbo7.3]

http://www.ford-trucks.com/forums/1183710-new-toys.html

check this thread out for a link to the light and feret adapter. he also has a good video of how to time the engine.