3rd gear power loss

[F1scamp]

I am having this sporadic power loss when going into third gear at high load that I can't seem to pinpoint. Whipple tune w/ modified cam timing. All whipples safety's off, and also turned off manual trans protection with hp tuners. Happens with all pullies. No different with using the WOT box or not. When data logging I can't seem to figure out what is going on, no knock, commanded throttle goes to 87%, but the throttle only goes to 34% on the shift. Does not recover if I let off and stab it, but if I roll back in the throttle will go up to 55%, shift into 4th and its back to 87%. Thought at first it was running out of fuel so I put a dw400 and a voltage booster with no change. I have had the issue intermittently for a quite awhile, but it is showing up much more consistently now. Anybody seen this before? Any ideas?

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[ugstang17]

If you were running out of fuel you would have had a lean indication at higher RPM on AFR1,2. STFT's would have gone whacky to add fuel and failed. With respect to this the next question is to determine if you are running out of fuel injector.

What is the setup? What size injectors? E-85, 93, or 91? Stick shift or auto? Before speculating its the tune inspite of your changes...I'd like to know more about the setup. Otherwise we can throw spit wads at the chalkboard all day speculating and never get in the ballpark.

 

[Tommy V]

Sounds like you have some torque manangement kicking in.Log torque source and see if anything shows.Usually when throttle closes it is some kind of tq management.

 

[Ruiner46]

I'm no expert, but if throttle is getting pulled by the ECU, it could be related to the torque tables. You need to log some parameters that show the commanded vs calculated engine torque. If the engine brake torque exceeds the torque request, the ECU will pull throttle, but things might be different at WOT. You'll get better help on the HPTuners forum.

 

[Jay-rod427]

Look at the torque source pid. that code will explain a lot.

 

[ugstang17]

Roush proclaims they do not use any protection strategies in their tunes, but I learned otherwise. After speaking to Roush engineeing about similar issues I was having on a 2013 turn-key issue and then datalogging throttle position v command and torque source along with typical fueling and sent it to VMP Performance they concurred with my suspiscion. I ordered a tune from them and the car was a night and day difference.

But all this said is simply speculation without more detail on the setup and rule out a few things. Simple process of troubleshooting. Eliminate probable causes first. Tuners 99% of the time will assume you have not done this (because most just blame the tune with no backing) and blame it on mechanical because "their tune is on 100's of cars with the exact same setup and those cars are not having any issues". Steal their wind by working the problem first. Then when you have verified that fueling is good, the MAF is clean, the TB is clean, the intercooler and intake plenun (on PD setups) is clear of oil, no belt slip, bypass valve is working, no unmetered air getting in, the fuel filter is fresh, the plugs are the brand they prefer and gapped where they want them, O2 sensors are functioning correctly, and no codes, then you can smile and say, "Okay stud, I've complied with your wishes and everything is working. Now please do your part and review these datalogs and correct the tune".

 

[Roh92cp]

is it possible turning off manual trans protection is causing this, I've read with that off some strange things can happen.

 

[F1scamp]

It's a stage 2 whipple kit with 3.625 pulley right now, 72lb injectors, long tube headers, stick. I just did my normal first of the year maintenance, new plugs, compression/leak down, new o2 sensors, cleaned filter and throttlebody, lof, The problem has occurred sporadically for a year or 2, but seems to be getting frequenter, or I am pushing the car harder and it is causing it. I will have to look at the logs again, but I am pretty sure I logged the torque source pid. Short term fuel trims stay within 5-6% when the issue is occurring. I am almost positive it is some sort of torque management, but I am definitely missing something.

 

[F1scamp]

is it possible turning off manual trans protection is causing this, I've read with that off some strange things can happen.

Does it either way, on or off doesn't seem to make a difference.

 

[Jay-rod427]

Torque source PID will tell you if it's traction control related, torque management, shift truncation, or something else. Whipple tune?

 

[F1scamp]

Whipple tune that the cam timing was tweaked by Tasca. Did it before the cam timing tweaks also.

 

[ugstang17]

It's a stage 2 whipple kit with 3.625 pulley right now, 72lb injectors, long tube headers, stick. I just did my normal first of the year maintenance, new plugs, compression/leak down, new o2 sensors, cleaned filter and throttlebody, lof, The problem has occurred sporadically for a year or 2, but seems to be getting frequenter, or I am pushing the car harder and it is causing it. I will have to look at the logs again, but I am pretty sure I logged the torque source pid. Short term fuel trims stay within 5-6% when the issue is occurring. I am almost positive it is some sort of torque management, but I am definitely missing something.

Are you running oil separators on the setup? If not it may be that you have oil collecting in the intake. This can cause knock and create other issues as it messes with the AFR mixture when oil finds its way into the cylinder. I mention this because of the key phrase "its been getting worse", which indicates to me from what you said that the car ran fine after the initial install. Had this been an issue from day one I would be more quick to jump on the tune band wagon but at this point a few things need to be eliminated from the equation before that can happen. Just went through this on my setup. Just a part of troubleshooting. So you may wish to create the symptom and datalog it. Then look at AFR bank 1,2 look at Lambse 1,2 and knock. The oil will create detonation that will generate knock and pull timing. Another thing you MAY be dealing with is a phenomenon called "FALSE KNOCK". This can be induced by a recent change in exhaust or suspension that generates NVH that can be picked up by the knock sensors and mistaken byt the ECU as knock because the reosnance is in the 10-12K hertz frequency teh ECU look for in the knock sensors to monitor for knock. So recall any mods since the FI installation that may correspond closely to when you started having this problem and review any places that may have interference and causing bainging sounds.

Good luck.

 

[F1scamp]

Yeah, it's not knock or false knock, the sensor's are in the negative adding timing the whole pass, actually seeing 21-22 degrees. It does have catch cans.

 

[Tommy V]

Hey man when looking at torque source at wot in that gear do u see any numbers come up or just it just stay at 0.

 

[ugstang17]

Yeah, it's not knock or false knock, the sensor's are in the negative adding timing the whole pass, actually seeing 21-22 degrees. It does have catch cans.

That's good. I figured running sour mash you'd be somewhere around23 degrees depending on boost level. Roush measures in mm so I don't know what your pulley equates to but guess its around 12psi peak.

So the problem may have been existent the whole time you just didn't start noticing it until you started leaning on it harder I am guessing. Then as mentioned the next thing is the tune. I troubleshoot for a living, so its not in my nature to just start guessing without getting the fuller picture and eliminating as many probable faults as possible, Sadly and i have already said this, Whipple will likely not admit that what you are seeing is torque strategy related....just as Roush would never admit the same thing to me. In my case I noticed the problem I was having from day one. Yet Roush would only tell me I needed to upgrade to the phase 2 package. Always the upsell.

That's all I got. I AGREE as well that it appears tune relATED.

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