u7153 2003 f150

[f150screw]

I am having a problem and I hope you can help me figure it out. I have the u7153 predator and i have an 87 octane tune on my truck everything seems to work fine untill i am running 65mph+ on highway, with and without a trailer (maybe 1,000 pounds with). when i accelerate from 65mph and up either easy or punch it, it sounds like a light rattle and i can't figure out what is doing it. it does not do it in town even when towing. am i running lean at higher speeds or something? like i said it happens at part throttle and full at 65mph+ I have 4.88 gears, 35inch tires, 2wd, flowmaster exhaust and a Brute force CAI and your programmer.
thanks
jason

[kmac1]

My first guess is that it's a little lean. You will see the most load on the engine at higher speeds due to wind resistance and the power needed to move it along at speed. The reason I say lean is because you are using a tune designed on the stock airbox but you have the Brute Force CAI. This will change the maf curve slightly. If you have the stock airbox I would try installing it and going for a ride to see if the issue goes away. If it does then your tune will likely need to be richened up in the maf curve.

Kevin@Diablo

[f150screw]

on the u7153 there is no maf curve adjustment adjustment so how could i richen it up in that range? sincethere is not one is there anyway to get a maf curve adjustment added to my u7153? maybea custom tune somehow?
thanks
Jason

[f150screw]

Kevin, you say the predator designed to work with the stock airbox does that include the stock air filter? I have read your manual for my unit and it always says WOT for a lot of the adjustment but on your site on the page that gives you the description on what my model will do it says it adjusts fuel tables but it does not say only at WOT like the manual. so which is wrong the manual or online? maybe my unit does have an adjustment that will help but it is labeled wrong.these are what it says it can do.

Performance Tune for 91 octane
U7153 Specific Features:


Global Spark Adder -6 to 4degrees add or subtract

3000-6000rpm Timing Table (+10/- 40%)

1000-2500rpm Timing Table (+10/- 40%)

Injector size adjustment

1000-3000rpm Fuel Table (+40(rich)/-10(lean)%)

3000-6000rpm Fuel Table (+40(rich)/-10(lean)%)

Idle (+/- 20%) (400-1200rpm)

Rev Limiter , drive and neutral 6400rpm, max

Full Throttle Shift Points RPM

Part throttle Shift Pressure per gear

WOT Shift Pressure per gear

Global Line Pressure adder 0-50psi

Torque Modulation ON/OFF per gear

Re-Calibrate Speedometer for Gear and Tire Size Changes

Internet Updateable

All standard DiabloSport Predator features
just need some help so my truck will run correctly
thanks
Jason

[kmac1]

I would say your best bet is to work with a Diablosport custom tuner to dial in the fuel trims. They'll need you to monitor the long and short fuel trims and the maf voltage to get an idea of how far off the maf is.

Kev