I have a 2003 7.3L Excursion. I am doing a suspension upgrade through Cary at CT Performance.

I would like to get better gas mileage without getting too crazy. I want some advice on a chip & tunes. The goal is better gas mileage while keeping it simple. Not sure I want to start messing with Exhaust, gauges, etc...

The key for me is SIMPLE. I am probably already a bit beyond myself on the suspension upgrade.

Better mileage would be awesome.

Any ideas would be much appreciated.

Thanks

 

Good choice, I'm sure Cary will hook you up!

I've had 2 motors break, arguably from making a poor tuner choice.

I will say that the DRIVER is most responsible for MPG. My (ex)wife regularly got over 20mpg in our 2000 7.3 X - but the best I ever got was 18.5mpg, hand calculated. The best thing you can do is make sure you don't have boost or drive-pressure leaks and the engine is otherwise in good working condition.

I highly recommend calling Brian at BTS for a chip. Keep in mind that people who have only used one tuner are not very sources of information...

 

SSJ -

Thanks for the info. Don't want to do anything to hurt the truck but it's only getting 9.5 in town. Thats with either one of us driving.

Cary is selling the TS Chip with custom tunes. I just want to improve city & highway gas mileage.

 

That doesn't sound right, you should at leasts be getting mid teens... I would make sure to change your fuel filter and air filter to make sure she's running clean. I'm running the DP tuner on the 85 econo tune and am getting about 17.5 mpg city and 21 ish on the hwy. I have no complaints with it.

 

Cary at CT told me to do a hand calculation. I thing the Average MPG monitor on the ceiling may be way off. I'll let her run a tank in town & then do the math. After the first tank I'll change all the filters & run again.

If I can get 17 & 21 MPG I'll probably blow off the tuning. May add the gauges anyway, on Cary's recommendation as a diagnostic tool.

 

The 'computer' aka 'lie-o-meter' is not considered accurate at all. Neither is 1 or 2 tanks hand calculated. There are just too many variables in filling the tank. The only way to attain a reasonable level of accuracy is to calculate over several tanks of fuel - the more ya do, the more accurate you can be.

That said, I seldom see anyone reporting less than actual MPG on the lie-o-meter - actual mpg is usually not as good as indicated...

Fuel filter is not likely to increase MPG and it takes a NASTY air filter AND a heavy foot to see significant decrease from an air filter. If the filter minder is working and you can peg it doing a 0-60mph run, this may be a contributor.

The EBPV (exhaust back pressure valve) and the WG (waste gate) can cause a major drop in MPG if not operating properly - but like I said earlier, boost (and drive pressure) leaks are far more common.

First, I recommend running the on-board diagnostics using AE or similar and seeing what shakes out from the KOEO, KOER, Buzz Test, CCT, Rotational Velocity, switch test, and also determine ICP values and IPR duty cycle, etc.

Next, look at the up-pipes - specifically where they go into the collector behind the turbo (you'll need to look from underneath with a bright light). Any staining or discoloration at the top of the pipes is an indication of drive pressure leaks. All PSD's eventually leak here. Although this will contribute to poor MPG, it has to be really bad to do alot of harm. Leaks here hurt power/MPG and drive up EGT (exhaust gas temp).

Then, build a boost leak detector ($5 ??) and check for turbo boost leaks. Probably the most common place for leaks is the boots between the 5way plenum (aka 'spider') that sits in front of the turbo - and the heads. The worm clamps ford used here tend to loosen up over time.

This is a 3" PVC cap with a 1/4" NPT hole tapped in it for a schrader valve. My new 'fancy' version also has a cheap pressure gauge installed in it.


Remove the lid of the airbox from the the intake tubing and clamp your 'boost leak detector' in its place. Now add about 15psi to the intake and spray soapy water at all of the boot connections, the spider to turbo flange, the plenums on the heads, etc. and look for leaks! You'll wanna use a bright light and a mirror-on-a-stick so you can see everywhere easily.


Unless one of the boots is torn, you can clean them up and re-use them - but there are better options. Same goes for the worm clamps under the spider. If (when) you find leaks, the minimum you'll need to do is remove the boots, thoroughly clean and degrease them, the spider and the CAC (charge air cooler - aka intercooler) pipes before re-installing them.

Few people will actually admit it, but the MPG gains from using a chip are overstated. The absolute fact is you can easily get worse MPG and usually will when you get a chip. Remember, the DRIVER is most responsible for MPG. That said, the tuning can be optimized to allow as good or slightly better MPG, while improving the driveabilty and power the rest of the time. Its common for folks to say that a chip netted them 2-3mpg, but nearly unheard of for anyone to say they've done an average over 10k miles... I'm not gonna call BS, but I'm sure few people will find a significant net increase if they do.

Same goes for the stock muffler. With stock or GOOD tuning, the improvements from upgrading to a 4" exhaust system are negligible. With BTS tunes, my EGT's never topped 1200* even towing my 12k lb Toy Hauler and RACING up every steep grade I could find. Yes, it does run a little cooler with the MBRP exhaust, but its much louder inside the X now - I miss the quietness/stealthiness of the stock exhaust. Of course, I'll be running close to 600HP eventually and the stock stuff won't cut it for that - but anyone running stock injectors won't see a significant gain here.

Now the stock air filter box is a POS. When you lift the lid off, look into the intake tube toward the turbo. Any dirt or dust here is an indication the lid has spent some time not properly secured to the air box. I think the best mod here is the factory AIS intake, fords 'severe duty' intake system. These run about $200 and are literally a factory bolt-in application. This system uses a HUGE Donaldson filter (long life) and flows plenty of air for a stockish 7.3.

Good luck and keep us posted!

 

I like the Aeroforce Scan Gauge. It will read and clear DTC's, display every engine parameter the PCM monitors and can do some of the on-board diagnostics. It has (2) aux inputs so you can add EGT, fuel or boost pressure. These retail for about $250 and fit in a standard 2" gauge hole.

I have 4 gauges on my A-pillar, but really like the F650 dash piece. This replaces the part of the dash around the cup holder and panty hanger and allows you to add several switches and a couple of gauges. Do a search here and you'll find some great examples. The F650 part can be found for under $40 and you cut holes, add switches and paint to match or you can buy a ready-to-install product from Riffraff. If ya DIY, check out the switches available from these guys. They have a switch for everything, but will custom build one if ya need something they don't have!
OTRATTW

Here's mine under construction:

 

SSJ - thanks for all the great info. I am easing
my way into all of this. I am very concerned about the "lie-o-meter"
reading 9.5, (especially since you said it usually lies high) - hopefully an anomaly.

This may be heresy but the X is going to the Ford shop in
the next few days to have some keys & remotes programmed, initial
oil change, retrieval of door code (they r doing for free) and fuel filters.

I don't understand most of the Mod language and acronyms.

Can the Ford shop run some diagnostics & tests to bird dog
the MPG? If so, can you give me some intelligent questions to
ask them?
Basically may need a laundry list of questions since this is my
first trip to shop with this Excursion.

Many thanks for the guidance.

 

These acronyms are what they do when they hook the 'computer' up to your truck. These tests help identify problems by testing the various systems. The 'computer' will also show DTC (diagnostic trouble codes) that don't make the SES (service engine soon) lite come on.

They will need to drive it to determine what ICP (injector control pressure) and IPR (injector pressure regulator) Duty Cycle are. These values indicate the strength/health of the injectors and the system that provides the energy for them (HPOP - high pressure oil pump).

You can ask them to visually inspect for boost leaks as well.

Btw, this is YOUR thread. Ask all the dumb questions you want. The fact is, the average guy or gal hanging out here likely knows more about the 7.3 than the best tech at the stealership. Its not their fault, they are constantly trained on the newer engines and this old iron has been out of production for a long time now. It is also quite different from any other diesel ever produced - specifically the HEUI injection system.

Here's a quick read that explains the HEUI system:
How the PowerStroke injection system works

Here's another great resource for common mods and maintenance:
Welcome to guzzle's Ford PSD Web Pages

There are plenty more, hopefully others will post some links. The one acronym ya need to know is PMS - Powerstroke Mod Syndrome. Some might say I have a bad case of it, but I can quit anytime I want...

Also, there is a very knowledgeable group of Excursion owners up in the "king of SUV' section here on FTE.

 

Wow - what an education - great info.

I think I'll do the CT suspension mod, tires, wheels, gauges, air filter mod for now and hold off on any tuning.

Does the mod on your dash take the place of the add on gauges or is it in addition to?

My next task is to decide between Tymar intake and AIS. Does Tymar also use the Donaldson? May be a different thread on that one.

 

Sneltyr, which suspension set up are you going with from Cary?
3" drop shackle, 2"? Dual front shocks?

 

JDH,

I have a 2003 as well. Here is what I'm ordering:
Decriptions from Cary -
V code SD springs front
B code SD springs rear
2" hanger kit
My correctly valved Bilsteins 4ea
Adjustable Billet track bar
2" hanger kit
V and B code springs
30mm bar
New U bolts
Options:
2 extra front Bilsteins and dual brackets
Dual steering stabilizer w/Fox shocks

Going to run 33" - may go higher later but it's wife's truck
And she is 5' 4" (told me she was 5' 5" for 17 years & I found out
she was fibbin

 

Thats exactly the set up I ordered. He did not send me a 30mm bar though, make sure he is sending you the sway bar...if not just order a hellwig or grab one from a junk yard.
If you need any help let me know, I just did it last weekend and its still painfully fresh in my mind.
With that exact spring swap and 33.5 inch tires on 20" rims I gained 6" in the front (37 inches prior to 43"). People are going to tell you that you "may" be a little low in the rear and its an optical illusion etc... its not, you will be low in the rear. My suggestion is to go ahead and order a 3.5 or 4" block now. You can order from top gunz customs. Hollar if you need any help, good luck!

 

Actually, that's not true. A persons experience, good or bad, should not be discounted just because he's only ever used one tuner.

A lot of very good info can be learned from people who have only had one tuner.

Stewart

 

Well put Stewart, reps to you!

They sure can! They can also make your wallet considerably lighter too!

Stick with us here on FTE and before you know it, your truck will be running in top condition.

Per the email I sent you, where in The Great State of Texas do you call home? I have an AE (performs many of the diagnostic functions the Ford tool does) and would be more than happy to see what (if anything) is wrong with your truck.