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Here's another random thought. If your fuel pressure is indeed low, you might want to make sure you don't have a fuel leak between your fuel pump and the fuel hat. I've helped someone diagnose a car with this issue and the fuel was bleeding off into the fuel tank.
 

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The Fuel Rail Pressure Sensor is how the OBD2 gauge would be reading fuel pressure. You should be at 39-40 range idling and cruising, under boost mine raises to 60+ but some of that has to do with tuning and also amount of boost. Regardless yours is low if it is indeed reading from the FRPS like mine does. One time I changed my tune over for new exhaust and was getting only 20-29psi fuel pressure (from OBD2 gauge) and the car was hesitating and not running right. It also threw a code for low pressure but that was because it dipped under 20psi for a second. Weirdly enough I was doing some other things to the car, retuned it with the same tune, and it cleared itself up over a drive or two.... I data logged all the fuel system and no bad duty cycles or anything so mine was tune related, it was like it was learning or fighting itself for the first few drives. Then was perfect. Yours seems to be a bigger issue though, and I think Catmonkey is correct in that it could be a fuel leak bleeding off pressure. Really though, datalogging is what needs to happen at this point before throwing more parts at it.
 

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If it is 70F ambient then cruising light throttle I would normally see 75-80 IAT1 and 105-115 IAT2. Getting on it it could climb to 130+ at this ambient temp. I have the same H/E, tank. The three most important things to monitor (on a street car) in my opinion, are: IAT2 (if it's over about 130 don't even think about starting a pull, you'll be down power from pulled timing anyhow and if running pump gas not worth the risk), Battery Voltage (14v+, if this ever drops you can go lean, and have all kinds of weird ECU issues as well, not to mention OEM alternators suck), and Fuel Pressure (if it's not 39+ on the OBD2 gauge, reading from FRPS, then something isn't right, and should only be getting on it CAREFULLY to get datalogs).
 

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You had mentioned you put in the DW300s, I'm assuming without a tune update? Did you confirm what the fuel pressure was at with the stock pumps? I'm just wondering if installing the aftermarket pumps without a proper retune for them is compounding any issues...
 

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Discussion Starter · #25 ·
As far as the Aeroforce, it would help if you knew what firmware version you had to look up the right set of instructions and related parameters. Something back there in the recesses of my mind recall something about doubling the values because of the dual pumps on the GT500. I'll have to look at mine tomorrow, but I know it's different platform than the 2007-2009 in terms of gauge parameters. I think the firmware data is on the back of the gauge. Aeroforce has all the manuals available for download on their website. Live Link will probably be a better alternative if you data log.
Not sure why it would do that, seeing that the reading is from the rail.. pressure is pressure, regardless of whether its 1 pump or 7. Pretty useless gauge if you are having to do math on the fly and drive the car, even if it is just doubling the number.
 

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Discussion Starter · #26 ·
The car is going in Monday for an updated tune. I'm going to try some datalogging this weekend, but worst case it gets done Monday. It was suggested that since the Failsafe Mode will active without throttle input (approaching a stop sign in 2nd gear, just letting the engine wind down) that it could be a throttle position issue. I did pick up a new factory throttle position sensor from Ford just in case, but think I need to also pick up the TPS's at the pedal as well. Unlikely at 14k miles the sensors are bad, but I'm wondering if theres a communication issue between the two or the difference in reading between the two is too far out of the parameters. Typically with TPS issues, you would get a light. Unless Shaun turned that feature off in the tune.

We shall see how Monday goes
 

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Not sure why it would do that, seeing that the reading is from the rail.. pressure is pressure, regardless of whether its 1 pump or 7. Pretty useless gauge if you are having to do math on the fly and drive the car, even if it is just doubling the number.
Yeah, like I said it was somewhere in the back of my mind. May have had something to do with duty cycle. I don't recall the circumstance.
 

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Discussion Starter · #28 ·
No worries, all information is good to have. I appreciate you trying to help!
 

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Yeah TB is definitely a possibility for failsafe but I was going off of the lean condition for most of my suggestions and being under heavy throttle. If it turns out to be a throttle body issue then that's easy, and it sounds like that's exactly what it is since it happens coming to a stop as well. It being dirty on the backside of the blade can cause issues as well.

As far as what Catmonkey refers to about doubling. That should only be when datalogging Fuel Pump Duty Cycle. If it reads .50 you're at 100%. However, my Aeroforce gauge doesn't even let me see this, I have to datalog it with Livewire software on the laptop. I can see fuel pressure though, which is read based on the FRPS.
 

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Discussion Starter · #30 ·
I took the VMP TB off today, actually pretty clean. I cleaned everything just for good measure and replaced the battery as well. It wasnt giving me any issues, but wanted to rule it out as it was getting up there in age. I've tried to eliminate the things that any vehicle would have happen to it, regardless of mods.

I reset the TPS by turning the key on ACC, pressing the accelerator full down and full up. Does have give an audible indication its reset. I do have a new Ford TPS, however I dont want to open the bag and just shotgun parts at it hoping I find the issue. If its the TPS it will show up on Monday during our tuning.

As far as the leaning out, I guess it is possible that the leaning is due to the Failsafe Mode, rather than the FSM caused by the leaning. Without knowing exactly what is on the current tune, the possibilities are almost endless due to no codes to know where to begin. Its possible there is a code that was turned off in the tune.

The car goes in for a new tune on Monday. Current plan is to write a basic tune and try to replicate the FSM while datalogging. Should be able to catch the bastard. After identifying the issue, we correct it and proceed with a new tune reflective of my expectations of the car and its use and the new elevation.

One of the most frustrating things is looking back through these forum posts, some of them having the same symptoms...but the OP never comes back and gives the root cause.
 

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Discussion Starter · #31 ·
Hi All,

Wanted to update the group on the progress of the car at the dyno.

Its confirmed the leaning out was a symptom of the FSM, not the root cause. The SCT tune that was on the vehicle was taken off, a safe tune added to attempt to replicate the issue and track it through data logging.

The answer I have currently is the Torque Errors other members were posting about. The tuner is currenlty making incremental adjustments to get the car dialed in. Was just reading on some of BJ's previous posts on this. Car is making stuuuuupid power, we are just trying to get it dialed in and running correctly.

Will update when we have it correct.
 

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Good that it appears to be a tune related issue and not a mechanical failure, but on the flip side, if this is tune related why didn't the previous owner experience the same problem. Or if my memory is correct, you said the car initially ran well for you too. I can't see a tune just going bad unless it was corrupted, and then a reload would fix that. If that's a wrong statement, feel free to correct me cause I'm not a tune expert...just basing my thoughts on general software experience.
 

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It sounds like you're on the right track. If my initial post sounded a little too much like "here we go again", this is why. You're not the first guy to buy a modded car, allegedly tuned by [insert world's greatest tuner here], only to find out the tune is crap, but only after throwing a ton of parts at the car, because it-can't-be-the-tune. Not that you got too sucked into the latter. Many times previous owners get frustrated with their cars with similar types of conditions and just want to unload it and will say or do anything to get it off their hands. It could also result in a car that has engine damage or will in short order if the purchaser thinks flogging it will make it better. This includes trading it in on another vehicle to a clueless dealer that just wanted to make a sale. I'm sure this is not "the rule", but you tend to see more issues like these posted in forums when things don't pan out with the new purchase.

If you happen upon this thread, know the following. Once a tune leaves the hands of the tuner and converted to a mailable format, there's no way to tell what is in the tune from someone going behind them. If AEM was telling him it's not the tune, they would have to be looking at the tune they initially sent the customer, which may not be the one in the flash tool or residing in the car's PCM. At least this is how it works with SCT's software. I'm guessing HP Tuner's software has similar protections. If someone needs to subsequently tune the car, they will be starting from scratch, unless they have the tune in the original readable format. In rare circumstances a tuner will give a customer readable format, unless the end user is an SCT Pro Racer (single licensed user). Most tuners will not make that accomodation. Only a data log can tell you if a tune is doing what it needs to do. But it's going to take it someone who can interpret what that log is revealing to detect the problem. Caveat Emptor! If a deal seems too good to be true, it may be.

@USMC53CHIEF. I hope this turns out to be a diamond in the rough.
 

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Good that it appears to be a tune related issue and not a mechanical failure, but on the flip side, if this is tune related why didn't the previous owner experience the same problem. Or if my memory is correct, you said the car initially ran well for you too. I can't see a tune just going bad unless it was corrupted, and then a reload would fix that. If that's a wrong statement, feel free to correct me cause I'm not a tune expert...just basing my thoughts on general software experience.
If the tune has critical error detections turned off, it may have been detecting faults but unable to broadcast them. At some point adaptive controls quite trying to correct errors when things are too far out of range and goes into failsafe mode. But none of that happened in a vacuum. I think there was likely some ****ery afoot.
 

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If the tune has critical error detections turned off, it may have been detecting faults but unable to broadcast them. At some point adaptive controls quite trying to correct errors when things are too far out of range and goes into failsafe mode. But none of that happened in a vacuum. I think there was likely some ****ery afoot.
Good info John, and you accurately read between the lines of my post. From my pea-brain, tunes just don’t go bad. So if “his” tune is causing the car to enter FSM, then I can’t see that happening all of a sudden provided there are no equipment/component failures in the car. So either this gremlin has been lurking for quite some time, or there is an equipment failure not yet found.
 

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Mike, I've probably flashed more tunes than the combined non-tuning group on this forum, but would defer to someone that tunes for a living. I'd bet money it was a prexisting condition. While I've heard others proclaim their tune somehow became corrupted, I have only had one download fail to complete in those hundreds of times I've reflashed a tune revision. On the download failure, the flash tool had me restore the stock tune and start over. I've been using SCT's Advantage software since 2004. I think this one failure was a firmware update I made on a used X4 I purchased. I checked and found a newer firmware update that probably corrected the issue. SCT makes mistakes too, and their tech support is second to none. This was on my 2015 F-150 and happened very early in its history. I recall it was a canned tune, because SCT had yet to map the strategy and that was all that was available. I've never had a tune corrupt on me once it was downloaded to the PCM. Can it happen? Yeah, probably. It's electrical and static electricity and/or low voltage can do crazy things to a microprocessor. I'm more likely to believe it would corrupt the PCM over the tune. However, I'm more inclined to beleive it result in a non-running, no-start condition over some random operating error/MIL. But, things I've read in Ford's diagnostics lead me to believe otherwise. It seems to be a last ditch, if-all-else-fails replace the PCM sort of thing.

Now if you unplug the flash tool before the flash tool tells you the routine is completed, it will corrupt the tune. I've not had that happen to me either. At that point the car won't run and you may have damaged the PCM. It's possible a download of the stock tune and a restore of the tune can get you going too. Some advice tells you to hook a battery charger to the car to flash a tune, but I don't do that either. But if you don't use an external charger, make sure your automatic headlights are not on, along with the radio, a/c blower, anything that requires battery power to operate. On one occasion the flash tool gave me a warning that the battery was not in a condition to load a tune. That's when my OEM battery was starting to fail.

Has my car gone into failsafe before? Yes, but it's always been because of a tune parameter that I got wrong or the installation of some component that needed a different calibration to run properly. Turning off warning indicators is not a proper way to tune a car. If your tuner tells you that's how he fixed a problem, find a new tuner.
 

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Discussion Starter · #37 ·
Ok, lots to respond to here, so I will try to answer all in one go. Its awesome how much time you guys are putting into helping me out and I appreciate all of the feedback

As we have been going through this, Jose (Who I bought the car off of) and I have been speaking everyday trying to work through it. I'll say it again, I dont know Shaun and I've never been to AED. That being said, even the folks at the current tuner have a lot of respect for the cars and tunes coming from Shaun, so at face value I do have to think he knows what hes doing. Even the owner of the shop sang Shaun's praises. Obviously everyone can make mistake or have a bad day and overlook something. One of the first questions;

"I thought the previous owner did not have any issues with the car." Correct, however FSM did flash in the every mornings (sometimes, but very seldom). Jose said the car would flash FSM, but the car did not perform differently. This was addressed with Chris (original owner) and was told the FSM kicks on if the car is run prior to the coolant temp reaching 165*. He was told it was build into the tune. Its also important to note that Jose never dragged the car, never tracked it and judging by the new LED headlights being wired backwards and him not knowing, I dont thinkn he drove it at night either. Car was completely babied. When we test drove it, he did make 3rd gear pulls and car performed well.

"I didnt think it was possible for a tune to become corrupt." Same here. I did reload the tuneand noticed one of the settings was RPM at Idele being set at 900. Prior to me reloading the tune the car idled below 900 and post reload it idled at 900, so I thought that would fix the issue, however it did not.

"What kind of tune did Shaun put on the car?" Great question. Here is where I tread lightly in an attempt to not bad mouth a guy or his business while only knowing half the story. Let me start at what is known to be the beginning. Chris had the VMP TVS and the VMP 67mm TB installed and had a VMP tune via SCT XCal4. Only the above "FSM due to coolant temp" issue was disclosed. Once Jose reached back out to Chris when I was having issues, Chris advised he had all the email traffic between him and VMP. I found a portion of emails that show Chris advised VMP there was a FSM issue. Here is a copy paste from that email. I've taken Chris's last name out. This was only disclosed to Jose AFTER Jose advised he sold the car to me.
Travis (VMP Performance)
Mar 9, 17:51 COT
Thank you for the update.
Chris ****
Mar 9, 12:38 COT
This is a follow-up to your previous request #7136 "Fail safe mode"
Old case but just wanted to close it out. The fail safe issues I was having have not reappeared since I reported it. There were also no codes found when I checked.

Jose wants to install more parts after he buys the car and wants it tuned by Shaun. He has injectors, CAI, BAP, Exhaust, HE, Thermostat all installed and the vehicle is towed to Shaun for tuning. Jose advised he didnt have an appointment wit hShaun and that Shaun squeezed him in. "If the tune has critical error detections turned off, it may have been detecting faults but unable to broadcast them." Bingo. I'm stabbing in the blind because I cant see any codes. My theory is that Shaun probably put a "base tune" that he has put on similarly modded GT500's and went with it without verifying the small details. I dont think it was ever a performance issue because Jose only drove the car short distances around town for coffee as an example. I will say I am a little less than impressed with Shaun's customer service, however I do keep in mind I was not his original customer and have given him no money. So, for what its worth..

Now for the current tuner. Because the tune is locked, there is no way for Alex (current tuner) to know what is going on with the tune. So Alex removed Shaun's tune and set a safe tune to just get the car to run, not looking for power just trying to ge tthe car to run without going into limp mode. He was able to see the TQ calculation perameters were not set correctly and has verified they are now accurate. Now instead of going into FSM on an aggressive throttle input, it is alerting on decel. We have a identical 67mm VMP throttle body we are swapping to see if the TB tensiometer is working correctly. There are quite a few articles on here about customers having issues with TB's causing tune nightmares, so we will see.

Alex has given me no reason to doubt his abilities or for me not to trust him. As he has data logged and dug into what the car is telling him, the data is lining up with the information Jose and I are finding about the car. I dont think the car is broken, I think its a small issue that just needs worked out. And yes, I did change the battery.
 

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Discussion Starter · #38 ·
Also worth mentioning I called VMP about this issue a week ago, followed up with a detailed email and mod list and havent heard so much as a mouse fart out of them. Once I get a chance, I am going to ask them for information about Tech Request #7136 and what the details were. If the throttle body is bad, I'm going to be pissed because it would appear it could have been bad all along (when chris bought it) unless, the TB and TQ error are two different issues.
 

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This was addressed with Chris (original owner) and was told the FSM kicks on if the car is run prior to the coolant temp reaching 165*. He was told it was build into the tune.
Wow, talk about too many cooks in the kitchen. Can you elaborate on the statement I quoted above? It can interpret it a few different ways. Every cold start is going to start out at something close to ambient. I'm not understanding what condition failsafe is occuring below 165* when every cold start is going to be below 100*. Is it not reaching 165* ever, or sometimes it does, sometimes it doesn't? What are your normal ECT temps when the car has warmed up? Are your ECT temps irratic? A faulty ECT sensor can give the PCM incorrect information that the PCM relies on. If the thermostat is not keeping your car in the right operating range, you might consider using a different one to rule out any issues with failsafe since this issue doesn't appear to have gotten the attention it needed from the outset, not from a mechanical perspective. Believe it or not, I've seen thermostats installed the wrong way. It might be worthwhile to open up the housing and find out what's in there and that it's installed correctly and functioning properly. I have a Reische thermostat in my car and I know there are coolant related values I needed to modify in my tune. I shoot for an operating temperature of 182-185* with my fan settings, but it will run cooler than that in the winter, so it is addressed in my tune. However the only time I've ever experienced failsafe from coolant temperatures was when an engine got too hot.

You know if the first tuner tunes the car for mods A, B and C and then you decide you want mods X, Y and Z and send the car to a second tuner, the first tune is pretty much useless without removing the last set of mods. That's an over simplified statement, not knowing the specific mods, but you can't blame the first tuner for problems outside of the parameters he's tuned the car. It's pretty critical to keep track of mods and know what specific parts were used and communicate those mods to your tuner. If someone else bought those parts, you can't be sure the information you get is accurate. Granted many parts can be identified by inspection, but some are not so easy. If you're not sure, let your tuner know that.
 

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Discussion Starter · #40 ·
Can you elaborate on the statement I quoted above?
Yes, this was just info that was passed to the guy I bought the car off and it was incorrect information. That isnt a parameter the engine is going to go into FSM for. Its just completely useless information for us and the only reason I included it was that was the only information we were given by the previous owner and what was known at the time.


but you can't blame the first tuner for problems
I'm not blaming anyone, I was just stating that the original tuner, VMP, hasnt been too helpful during the process. There are 3 mustangs in the shop at the moment, all have VMP 67mm Twins and all having the same issues. We have solved the problem, I'll address in the next post. I'm not trying to blame VMP for anything, nor am I trying to blame AED, just neither have been too helpful. Too be clear I wasnt interested in VMP support for the tune, more for product support for the TB. I've gotten more support from BJ on this forum than any of the previous shops... and I havent even talked to BJ lol, just reading his responses.

It's pretty critical to keep track of mods and know what specific parts were used and communicate those mods to your tuner.
Very true and this wasnt an issue for us. The only unknowns we had were what was in the tunes. Since AED had provided the last tune, I wasnt really interested in VMP's tune. It just wasnt relevant anymore. I get it, each tune is a tuners individual product and they want to protect it. However, without knowing what is in there or what critical functions are turned off it puts you in the blind. Normally its not a big deal, you just take it back to the tuner. In this specific situation, AED wasnt willing to take the vehicle back as me being a new customer to see what the issue was.

This is just more costly. The best way to deal with the situation above is to have a new tuner remove the old tune and start from scratch. When there is an issue with the car and you have to solve it prior to even trying to squeeze the car for power, it prolongs everything. This ties up the dyno for longer, sets shops schedules further back, etc and costs more. The most frustrating part is it would appear alot of these cars have the same issue and this problem has probably been there since day 1 of the VMP TB install. More on that in my next post.
 
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