Problem after mail order tune

[ksigatmsu7f02]

This is my first post in this section so bear with me.

Here is a link to a previous thread if you'd like a complete background updated as it happened, but I'll try to summarize it here as best I can.
http://www.svtperformance.com/forums/sn95-cobras-24/779955-new-custom-tune-engine-hesitation-cutting-out-4250-a.html

98 Cobra, JLT cold air, Bassani o/r X, IMRC delete, flowmaster catback,....think that is it....

I ordered a Livewire with custom tunes. Got the tuner in loaded the tune and teh car ran horrible, stumbling down low and feeling like it hit a rev limiter at 4000-4500 rpms, depending on the gear. Car is completely undriveable.

Tried datalogging but the Livewire wouldn't communicate with any opf my laptops, after going back and forth with SCT and sending it to them and them telling me that it worked fine, the tuning company finally had me send it to them where they verified it was in fact bad and they would send me a new one and have SCT retrieve my stock tune off the old one to send me a restore file that was supposed to correct the problems with my car.

SCT "broke in half" the memory chip in my old livewire supposedly while they were trying to get my stock tune off it. So they had me retrieve the stock tune off the new livewire, sent me a restore file off that and I loaded that and it made no difference, still running like crap on stock tunes or custom tunes.

Put it on a Solus Pro Scanner and it said no problems. Tested fuel pressure which was stable and within specs.

The tuning company has been very willing to help but nothing they do seems to help. To try some things on my own just in case it wasn't tune related I went ahead and replaced the fuel pump, spark plugs and wires. No change.

I datalogged today now that I changed that and noticed that when the RPM's get to the range they begin cutting out, my lt fuel trim values on both drop signifigantly. They rise with the RPMs and maf counts but once it hits the 'upper limit' they drop and stay low until I let off the pedal.

I can post the datalog if need be. Just need someone to point out how to....

Appreciate any help ya'll can offer. Been dealing with this for 2 months and the car isn't drivable.

 

[01yellercobra]

It really sounds like a tune issue. I had issues at certain rpms with some of my tunes. It was either from the fuel being way too rich because the MAF transfer function was off, or the MAF transfer function itself wasn't set up correctly. Posting up a datalog would help.

 

[ksigatmsu7f02]

Here is a link to my datalog from yesterday

http://www.wildhorsemustangclub.com/ksigatmsu7f02_datalog_8711.csv

The first 3 minutes is idling, then 3 of normal driving then there was a full throttle pull through part of 3rd gear.

Also, it does this in the stock tune. Didn't before loading the first custom tune, after loading that, no matter which is loaded it does this.

 

[01yellercobra]

Ok, I'm not pro, but a couple things stand out to me. It seems like you're running lean. Like at line 360 when I'm guessing you're at WOT for a quick burst. You're commanded A/F is 12.5. That's lean for a boosted car. Although there's a chance you didn't go far enough into it to switch to open loop since the A/F is still changing up to that point. The STFT's should show the commanded A/F as soon as you punch it.

My guess would be that you no longer have a stock tune saved anywhere. Somehow your stock tune was overwritten with the performance tune when you were working with SCT. Your performance tune still needs some work. You need to get a wideband and hook it up into your datalogging software. Otherwise you're just guessing at your A/F at WOT.

 

[ksigatmsu7f02]

Mine is n/a, not boosted. I'll pull it up and let you know what I was doing at that point. Just a minute....

360 Is at the end of my part throttle cruising but right up against the point where the car runs out of power. the 3 bursts after that are the full throttle, where you can see a high RPM of ~4900....this is where it runs out of power each time.

 

[ksigatmsu7f02]

My guess would be that you no longer have a stock tune saved anywhere. Somehow your stock tune was overwritten with the performance tune when you were working with SCT. Your performance tune still needs some work. You need to get a wideband and hook it up into your datalogging software. Otherwise you're just guessing at your A/F at WOT.

SCT told me my stock tune was corrupted or something to that effect and sent me a 'restore' file that was supposed to repair it and fix the problems but didn't do anything.

After loading that restore file it started throwing codes that I expected it to throw, like for the IMRC deletes on the stock tune, whereas it wasn't throwing anything prior to that after loading the first tune, which is when the stock file apparently was corrupted.

I may unlock the livewire and take it down to have the computer flashed at the dealer. If that fixes it then I'll know it was an SCT problem all along and they will have to reimburse me for that cost(the tuning company has essentially agreed to do so if it comes to that point and that fixes it), else I'm only out a little bit.

 

[NateTermi]

SCT told me my stock tune was corrupted or something to that effect and sent me a 'restore' file that was supposed to repair it and fix the problems but didn't do anything.

After loading that restore file it started throwing codes that I expected it to throw, like for the IMRC deletes on the stock tune, whereas it wasn't throwing anything prior to that after loading the first tune, which is when the stock file apparently was corrupted.

I may unlock the livewire and take it down to have the computer flashed at the dealer. If that fixes it then I'll know it was an SCT problem all along and they will have to reimburse me for that cost(the tuning company has essentially agreed to do so if it comes to that point and that fixes it), else I'm only out a little bit.

Who is the tuning company?

 

[ksigatmsu7f02]

Who is the tuning company?

At this point I'd rather not say. They have been very helpful in trying to resolve this and in getting SCT to see there was a problem with the Livewire when SCT told me they couldn't recreate the problem.

I'm not even to the point of being able to tweak the tunes as the car isn't drivable and does this with the stock tune reloaded. I'd like to reserve any comment on the tuning company until the point I can actually work with them and give them a chance to tweak the tunes. If you feel that mentioning the tuning company by name may indicate something I'll PM you but for now, I'd like to leave their name out as I don't see it being productive.

 

[ksigatmsu7f02]

Tuner sent me a new tune. Gave me alot more spark I know...not sure what else....said it was completely different. Has much more power down low but still hitting a brick wall at about 4500 to 5000. Any other thoughts?

To go into more detail, the car ran great. I drove it home, loaded the original tune off of what I know now to be a defective Livewire and ever since then it has had this upper limit in the rpms. Fuel pump change seemed to shift it from 4000 to 5000.

I'm going to get the car up in the air this weekend and inspect the fuel lines to make sure I didn't crimp one when I pulled in the driving the night I loaded the tune. It would be quite a coincedence but I just have this feeling still this has to be fuel related.....

 

[ksigatmsu7f02]

For future reference - problem was solved by cleaning the maf....wires were caked with crud...sorry to bump just wanted to add that...

Also, I owe alot to Bama tuning. they more then went out of their way to do everything they could to help me. They have re-written tunes many many times trying to correct this. Great customer service. I will be using them exclusively.