I just got a BTS in my Excursion & we made a new chip. While test driving my truck ran very underpowered. I've never found it to be powerful. We could only make 22 psi, same on the dyno. Stock it made only 146 hp. Around 250 hp with the chip & Steroid-T.

Checked but found no boost leaks. Fuel pressure 75-80 psi. Tried a Super Duty computer & that gained 12 hp stock but same with the chip. The truck only gets 11 mpg city & barely over 12 with or without a trailer on the highway.

It has a build date of 1999 so they thought the injectors may simply be smaller. They said my glow plug relay looked different from any other Ex they'd seen. Anyone know what all could be different on an early 2000 model Excursion?

They said they would do some research to try & find out what could be wrong with my engine. They felt that something is definitely wrong. It was even effecting the shifts of my new BTS. I have to go back down there soon to have some adjustments made to my chip. It would be good if i can be prepared with any ideas ya'll might have.

Thanks,
Matt

 

1 Could your wastegate be stuck open? 2 Front of engine on pass side manifold has a fitting with a exh sensor. I left that unbolted once...no boost all work. 3 Fuel pump low...temps up in the 900 without a trailer 4 worn oil pump? hmmm I have 431k on my 7.3 5. Back pressure closing? High temps. What kind of boost guage are you using? Computer or actuall?

 

Who is "we" as in made a new chip and who is "they" as in the shop?

 

All of the work was done at Brian's Truck Shop in Lead Hill, Arkansas. His son Cale does everything non-transmission related on the Ford trucks. He has a Dynojet dynomometer on which we made about 20 runs trying to figure things out. He uses Jody Tipton's chip burning hardware & software.

We disconnected the rod for the wastegate & it is opening & closing freely. I have my EBPV wired to a switch & can really tell when it is open or closed-which we tried & that is not the problem. Nothing is unplugged but i will look on the passenger side manifold again.

The most boost i have made since is 24 psi. It was evening finally down into the 70s & i tihnk that may have had something to do with it. It was in the 90s during our testing even with a huge fan in front of the truck. every run would lose 2-3 horse power just due to heat.

Still, Cale & Brian said that my truck should be making about 32 psi with their 100 hp chip. The chip does make 100 hp, but the truck is underpowered to begin with stock. We suspected the fuel pump, but there is plenty of pressure at the regulator. I easily see 900 degrees EGT with the pyrometer in the manifold, unloaded, no trailer.

They did not think it could be the oil pressure since the fuel pressure is good. Either the HPOP or a loost boost hose would be my most likely guess but nothing is making an obvious help me indication. Cale also used a huge scan tool & checked every single sensor & observed the readouts of everything to be perfectly normal. Also did an injector test. Nothing seems tto be malfunctioning.

That's why they though it might just be weak '99 injectors. From what i've read, the early '99 engines were underpowered, but had desirable single shot injectors. Anyone know if those injectors were indeed weaker? Build date was '99, not '98 as i think those weaker engines were from what i've read on this forum.

I have a huge Donaldson intake from SP Diesel. Similar to the Tymar. Stock exhaust. My Steroid-T module which taps in right at the sensors does still add a noticeable amount of power & smoke on top of the new chip. It modifies timing & ICPs via two potentiometers. Had to get a new one because my Diesel Innovations simply wouldn't start one morning this winter.

Cale told me that his chip should be making all the power the engine can, which made us think that it was a computer problem. Trying another computer laid out the same high end horse power. He tried everything he could think of chip wise, reburned several times.

For gauges i am using a BD-Power X-Monitor. It reads out of a BRV+ on the engine side, not the side going to the MAP sensor that is getting fooled. I believe boost to be accurate as this truck is not fast, does not begin to break traction. No tire shredding here, can't even chrip the tires unless it is raining. Every car & truck can pass me on the road, even floored. Still getting barely over 12 mpg. I just came from Boston where i got 11 mpg for 1.5 years solid. I thought i might see big improvement. Still the same with a trailer too.

Any more ideas?
Thanks,
Matt

 

whoa whoa, ok lets look at a few things here. I believe you typed stock exhaust, that will eat a little but not enouph to be wimpy. Has the funny BUZZ test been done on the injectors? If your injectors are say, weak you would still have some power. This is my thinking. If the programming is telling the injectors to stay open longer to dump more fuel in you would at least have black smoke. If you had low compression with that chip you would be dumping bluish smoke. I think something is keeping you from placing all of the boost into that engine. Im feeling as if we have missed something. Tranny torque converters going bad will eat a ton of hrspwr but you would be telling us about high rps and no go. Have you had any at all codes? How about a bad connection between the HVC harness? I think that was it or UVC anyway the valvecover injector harness. How about a spare cps sensor to try, mine has just went again but it runs like crap and am getting a new one today....Im just trying to brain storm with ya here. Troy

 

Thanks for the ideas Troy,

Transmission is a brand new BTS. You might call it perfect. There is smoke, all black. I can lay it on thick in low RPMs when i add my ICPs. It actually smokes allot as i lug through the hills in overdrive. When i shift into 3rd gear it cleans up. Gets really clean by mid 2,000 RPMs. When i hammer it there is just a mist of dark grey smoke even in 3rd gear. Governor is set to 3,800 & i don't get that high anyway. Yes, we did the buzz test on the injectors & they are all working properly.

Where are the connections for the HVC? We went through everything a couple times before finding no loose connections, & as i said before, he tested every sensor, watched them on a graph on his scan tool.

I carry a couple spare camshaft position sensors myself, had tons of trouble with those. Had the truck die in the middle of traffic a few times. I use Black RTV silicone on them but this one has lasted about a year now.

The truck seems to run just fine. You would never know that something is wrong with it unless you start wanting some power while driving. Putting it on the dyno was the real testimony. Fortunately, drivability is not an issue for me. Only low power of about 23 psi & 12 mpg.

-Matt

 

is it possible the injectors are just tired and worn out?

 

How about the throttle position sensor? Maybe your not hitting full throttle. Also what gears in the diff are you running? They maybe the reason for the mileage.

 

Gears are 3.73:1 with a 2006 Visteon 10.5. Has a factory locker which has proven to be near worthless on the farm. Would i have to be at WOT to make more boost when i'm already near 3,000 RPMs close to 90 mph in 3rd gear? I have it floored so i assume it to be. I will monitor the sensor & see what it says. However, i don't think the TPS would effect fuel economy, would it? I do not know if these injectors could wear out. The engine only has about 125k on it. They are working, maybe just not designed to provide enough fuel?

 

Your milage down and full black smoke conjures up more thoughts. The harness is in the middle of the valve cover top of engine and is integrated with the valve cover gaskets. To inspect the underside would be to remove the valve cover and make sure the connection is ok and the small black clip is still in place, although you would have recieved a code if the connection was an issue. As for the thoughts, there is sometimes too much fuel but that usually is low egr temps. Is it possible some cyl are richer then others? We need to ask ourselves that but the buzz showed all clear. Hpop not producing enough oil pressure at high speeds to keep up with popin the injectors? hmmm I dont know on that one. Were having the same problem here with another forum member here in AZ. I just spoke with him on the phone. Maybe some results will come of it and be posted to you too.

 

That would be awesome! My '95 Suburban only got 7-9 mpg locally, 11 once on a long distance interstate trip. The main reason i moved into the Ex was for diesel fuel economy. You can imagine what a disappointment it has been on the wallet.

I hope the other truck gets figured out. I had hoped my truck would have some obvious & simple problem. The thick black smoke only rolls out when i add my ICP potentiometer turned up all the way. The chip burns much, much cleaner, but the pot ads more power. The only codes i have are ICPs above/below desired. Those are from the Steroid-T's ICPs.

Any further ideas still greatly appreciated.
Thanks,
Matt

 

I get 19 to 20 on my truck with 373 and 140 gallons of fuel on a cc long bed 2wd. When I get loaded I get 6 to 10 mpg.s

 

You think it could just be that my truck is so heavy i'm not going to see improvement? Would mpgs not change when i pull a trailer? I get the same with or without. Your mpgs change as much as 14 mpg depending on load? Do you know approximately how much weight you're toting? My guess is that my truck weighs about 9,000 lbs.
-Matt

 

Man. Those unloaded numbers are impressive, but those loaded ones are abysmal. What are you pulling, aircraft carrier anchors? 10 I can see, but 6 is off the scale.

 

Well I get a 36ft fw and pull I-80 where if the wind stop everyone falls down, yeah im good at 6 to 8 mpg. Now when I run 70 to backwoods down to 40 then I get up nears 10 or so. I can also pull an airstream up to 90mph in 40mph crosswinds that flip UPS double trucks or I can pull a Fifthwheel toyhauler with a 20mph crosswind and max out at 65 before I just start dumping fuel money in the trash. It all depends. I-70 is my favorite cause I can scream through Illinois at 85 to 95 running a front door on the CB radio and a scanner....55 is too slow so I might as well do it right. lol