I need some advice first. I bought my daughter a used 2007 Mustang GT with 4.6 auto, stock engine, 20 inch tires and a CDC shaker AIC system. It had shorty headers. Unknown to me her and her boyfriend modified it by installing O/R X pipes, SLP Loudmouth 1 exhausts, Steeda Under Drive pulleys, Comp Cams Stage 2 XFI VSR Camshafts, 3.90 Motive gears, and 275/50R15 Nitro Drive Radial tires. They used a SCT XCalibrator2 Programmer to tune the car. Unfortunately, the tune installed a 1500 rpm idle on the car and an engine trouble light. Even going back to stock would not solve the problem. Ford had to purge the PCM and I had to put the Catalytic converters back on to get rid of the engine trouble lights. If I try to install the gear and tire changes with the XCal2, the idle goes back to 1500 rpm. The Ford tech says they can't help me and the programmer appears to have a glitch in it. I need to know if it would be better to have the XCal2 reprogrammed or just get a new programmer. The old programmer has three tunes on it from two different companies. I just want a tune to take care of the camshafts and the gears since the fuel octane and tire sizes may change. The programmer was bought in October of 2007. The car came with 255/40R20 tires which are back on it. I need some expert advice so I can get this car running again.
Get rid of the O/R X pipe, and get a free flowing catted X pipe. For a car that sees more street then track, you need back-pressure which you lose with an O/R X pipe. That will also take care of the Check engine light, then bring it to a reputable dyno tuner. That will take care of your problem, Mike. SCT Tuner.
I would go to www.sctflash.com and talk to one of the Tech Reps and see what it could be. Sounds like the tuner might have a glitch in it. I know i had a Xcal 2 that crapped out on be after 3 months. Was the tunes specific for that car with the cams? If it's a generic tune that wasn't for that car or a tune that's not for the cams or offroad mid pipe, then you'll need a new tune for those. Brenspeed has some good tunes for the 05 and up stangs.
Backpressure doesn't play that big of a role when you go from a stock mid pipe to an off road pipe. If would be different if you put a full 3 in exhaust on a semi modded car though.
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1995 Mustang GT-Heavily Modded-Sold 2003 Ford Lightning-Sold 1997 Saleen-5.4 conversion-Sold 2005 Mustang GT-Torch Red-Sold 2003 Mustang Cobra-Oxford White 2003 4Runner V8 Sport Edition 4X4
The first tune was for the crossover pipes and the tires. the second tune was for the gears. They were by Brenspeed. The third tune was for the camshafts and all the mods together as well as a stall converter that was never put on. This tune was made by Bamachips. This was when all the trouble started.
The idle locked at 1500 rpm and the vehicle quit shifting correctly. The engine trouble lights came on. I had the stock crossover cats put back on as well as the original 255/40R20 tires and the Ford mechanic had to purge the PCM to get the idle back where it was supposed to be. Everytime, they tried to use the SCT tuner it messed the idle up. Now, my speedometer is 15 mph slow. That is why I need to know whether to try to get the XCal2 fixed or go with a more modern programmer and get a tune just for the camshafts and gears. What really upset me was my daughter destroyed the warranty when they installed the camshaft and gears. The car only has 17000 miles on it.
i know with my diablo when i changed the gears it raised the idle for somereason but i just went in and changed it back. cant you do the same? and a custom made tune can be made be to shut the o2 sensors off so it doesnt throw codes. But definatley talk to the sct techs.
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2000 Black Mustang GT
Diablo Predator, Off road H Pipe, 3.90 gears Flowmaster mufflers, JLT CAI, Cobra R's
Short Throw,Zex Plugs, BBK UDP's,
Lakewood Lower control arms
Defeating the O2 sensors is what started all my problems. It caused some other problems and I ended up putting the CAT's back on. Now the shift is messed up ,the speedometer is off, and the idle rpm is too high even in stock or custom tune.
To top it off, SCT will not return my calls or emails. Bamachips, who wrote the last tune when all the problems started wrote answer my email either. I have been trying all day to get in touch with both of them. I have a $40,000 Mustang that is a piece of junk right now. Is there a decent tunable programmer besides SCT?
Wow, you are a patient father. Had I been in your daughter's position, my dad's thread would have read: "F/S - Mustang GT - Best Offer - Need $$$ For Son's Coffin." We actually headswapped my '98 GT in the dark so my dad wouldn't find out. Fortunately, the swap went off without a hitch.
Seriously though, I think you should start with the proper stall converter. Once you've got a mild converter that will work with the cams (the specs of which I'm not familiar with), you can call up a tuner and they can calibrate the speedo, deal with the aft O2 sensors, and at least ballpark a tune for you (obviously the "perfect" tune is unattainable unless you're on a dyno and you're monitoring A/F.)
If installing cats and resetting the KAM took care of the MIL, then you already know what you need to do to remedy that issue. The absence of the chip will obviously throw the speedo off, so you can either install the proper chip, or use a SpeedCal which will fix the speedo and do nothing else. Still, I'd think that you would want some element of tuning with those cams, which you can accomplish (along with your other goals) in the form of a mail order chip (not programmed by morons.)
Finally heard from SCT tech about 4:00 PM CST. They think the problem is caused by residual tunes in the XCAL2 since you have to enter a custom tune with the XCAL2 to enter the tire size and rear gear size. Since the tunes were made with the X/O and small tires, they figure the mods are interfering with PCM's interpreting what the idle rpm's should be. SCT says I should get a custom tune with the way the car is modified now: with the CAT's, large tires, cams, rear gears, etc. Does any XCAL2 users agree with this diagnosis?
I wish to thank every one for their input. I will hang on to the XCAL2 and get some new tunes for the existing mods if anyone still writes for the XCAL2.
Doug from Bamachips emailed me yesterday. The mustang is doing what it was supposed to do. My daughter ordered a race tune so it revs high for a quick takeoff and is not supposed to be used for street driving and shifts through the gears fast. Doug said he would modify the tune for me.
SCT emailed me also. They think the Ford technician may have changed my registry when they reflashed my PCM. I got the new registry number but my daughter's boyfriend never got the original registry number so I don't know if it is changed? SCT says if the registry number is different, none of the tunes will work correctly now. Since the XCAL2 belongs to my daughter's boyfriend, I think I wll just get my own programmer and and not have to deal with him anymore. I notice Brenspeed, Tillman, and Bamachips do not sell the SCT SF3, just the XF3. Is there any advantage to the the SF3's preprogrammed tunes?
Just goes to show SCT software in the Wrong hands can create havoc on the cars computer, anyone can claim to be a Pro, it's all in the person behind the keyboard..
messed up pcm with mods 
