Unresolved bucking issue

[Lunas Destiny]

Hey guys, first post on here. I have a 2019 gt with a troubled history. Seems previous owner cooked her well and i would see 230° head temps regularly. Got the car with 36k and am now at 48k. Got an engine replacement due to unresolved p0300 and sometimes cylinder 2 misfire. Engine bucked on a pull and I stayed in it for some carnage. I took out cylinders 2,3,7 and smoked the torque converter. 23 motor in and lo and behold the new engine had same issues. They found a tsb for a cat issue and replaced drivers side. I had some weird high end issues and to me it seemed the coilpacks got cooked and couldnt output what i needed. New granatelli coilpacks on and ever since I haven't really noticed an issue other than tone differences at times. Except last week when i went to make a regular pass on the highway and it started bucking again. I have sometimes been able to hear a noise coming from the front of the car when driving against high walls or fences. Tested the throttle KOEO and sure enough it made a noise that to me sounds like electricity building up due to resistance. Thought I'd post here for a before and after since a new OEM throttle body is on its way. I have had a weird bucking issue with the car and unsure if this is related or not. At idle the throttle angle fluctuates between 2 and 3°. On idle LTFT bank 1 doesn't move at all from 1.6% LTFT bank 3 doesn't move from .8%. STFT for both banks stay more on the higher side of 0-1.6 typically staying at .8 or 1.6 with small dips to 0.0. Fuel lift pump pressure desired is pegged at 57.87 and actual is at 59-60 psi. Fuel rail pressure desired is 400 psi, actual slowly increases 5 psi every 5 seconds at idle. After idling the car for 3 minutes after a drive the fuel rail pressure actual went from 936 to 1203 psi. Fuel pump commanded dc stays at 20%



I am hypersensitive and the throttle is tricky to get a linear press so I cant quite determine if there's a dead spot in The body or not. Here's a video of the noise, I plan on recording with the new one and see if it makes the same noise or not.

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[KingKona]

You'll get a lot better help when you communicate clearly and concisely.

Try again.

 

[luca1290]

The noise is 100% normal.

 

[Lunas Destiny]

No it is not. I've checked several other cars and they have little if any noise with them. That is why I have uploaded this.

The noise is 100% normal.

 

[Lunas Destiny]

Which part isn't clear? I have an intermittent bucking in my car and I am providing a history of the vehicle and all troubleshooting done thus far.

You'll get a lot better help when you communicate clearly and concisely.

Try again.

 

[shogun32]

At any point did you also get a new, unmolested factory spec ECU? This smells heavily of a bad quality tune.

Also what fuel are you using?
If not tune, id finger the injectors as potential source of trouble. You know there are 2 sets...

 

[luca1290]

No it is not. I've checked several other cars and they have little if any noise with them. That is why I have uploaded this.

Yes it is, it's the servomotor driving it, mine does it as well as many other cars of many other brands.

Anyway, if you know already for a fact that it's not normal.... why bother asking?

 

[KingKona]

Which part isn't clear?

Here ya go....

....previous owner cooked her well...

...i would see 230° head temps regularly...........

...I stayed in it for some carnage. I took out cylinders 2,3,7 and smoked the torque converter....

....23 motor in .......

....tone differences at times......

....a noise coming from the front of the car.......

....throttle KOEO......

...throttle angle fluctuates between 2 and 3°. On idle LTFT bank 1 doesn't move at all from 1.6% LTFT bank 3 doesn't move from .8%. STFT for both banks stay more on the higher side of 0-1.6 typically staying at .8 or 1.6 with small dips to 0.0. .........

....Fuel pump commanded dc stays at 20%

........a linear press.......

....The body...........

 

[Lunas Destiny]

At any point did you also get a new, unmolested factory spec ECU? This smells heavily of a bad quality tune.

Also what fuel are you using?
If not tune, id finger the injectors as potential source of trouble. You know there are 2 sets...

No, I have had the car for about a year and only been at the dealer twice for engine swap and cat install. They didn't suspect anything with pcm when they changed some configuration for the cat swap. I always run 93 in the car, I do have another noise that sounds very similar to air in the fuel line at the 90° bend AFTER the hp fuel pump. I know chances of actually having air stuck in the lines is slim to none with this fuel system so not sure what else could present as that. The throttle never made these noises when I first got the car, I also tested this with other mustangs because at 2500-4000 the squeal makes it sound like a turbo with a bad impeller. When the noise is louder than my exhaust I start to worry
It appears that when the engine was replaced it received a lot of old sensors rails injectors etc. I am guessing there is an air leak somewhere on the passenger side but it shares the same symptoms of the old engine minus the p0300 and p0302. All the plugs are consistent and I just changed them out last week just in case. I am starting to look at the fuel system to determine if it's a slowly dying fuel pump. Removing rear seat does not show anyone ever opening the system so that's a good sign it hasn't been messed with before. There's a surge I can't seem to isolate.

 

[shogun32]

There's a surge I can't seem to isolate.

Datalog both a normal run and a problem one and post up. There are some smart cookies here. I would also spend the Dyno time and log under controlled conditions and not on public roads and at various power and throttle profiles. But I'd first start with having the dealer force flash the ECU back to as built.

 

[Lunas Destiny]

Here ya go....

It's pretty clear to me but I forget others have different brains and thought processes.

I bought the car with 36k, coyote tick bad bad. I isolated it to the imrc system and confirmed by temporarily locking them out. When I first changed the oil it was burnt and thinner than anything I've seen before. Got a great bath. Cylinder head temps on casual driving always stayed above 215° but spirited driving went alot higher. Saw heat soak at 245° one time. This is irrelevant in my opinion because there's a brand new 2023 coyote installed from Ford due to engine failure. They never determined the issues but it was apparently the worst failure they've ever seen from a coyote. New engine in first drive threw a p03000 again. Dealer did catalytic converter as part of a tsb that was for my car. It doesn't meet the criteria for the rest of the tsb (no cel with dedicated bank misfire failure) so there's no point in taking it back to them. When the car starts hesitating or bucking there is an extreme exhaust tone difference like it's broken up. The throttle squeal is most noticeable at 2500-4000 rpm when I drive against walls and fences it echoes back. I can hear from the drivers seat its coming from the front of the car. Hence the video of the throttle body. The test performed was with the car in KEOE (KEY ON ENGINE OFF) criteria for throttle dead spot test and listening to this feedback noise.
I hooked up vcm scanner and logged some casual driving with small pulls not hitting full throttle in case it runs lean. I was referring to the data in the screenshot provided from vcm scanner. The throttle sits at 2°-3° at idle and I took a picture of where there's a significant deviation of timing being pulled for some reason. All throughout the drive test fuel pump commanded dc stayed around 20%. When taking the video of the throttle body I tried pressing the pedal in a linear fashion to determine if there's input issues, deadspots in the throttle, or hesitation. Considering the throttle only operates on one plane it'd be very easy to see these variations. If you need help understanding anything else please let me know....

 

[Lunas Destiny]

Datalog both a normal run and a problem one and post up. There are some smart cookies here. I would also spend the Dyno time and log under controlled conditions and not on public roads and at various power and throttle profiles. But I'd first start with having the dealer force flash the ECU back to as built.

Yeah im kinda limited as I don't have a laptop to run the software so gotta depend on others. It doesn't break up as much as I'd like it to (but also not at the same time) so it's hard to watch it. I've been trying to eye afr to see if it goes lean or rich in that state but haven't had any luck yet because I like to see cylinder head temp and trans oil temp at the same time on my gauge cluster and afr is juuuuusttt too high. I'll throw the short log I did of some regular driving and 2 hits up to 100 mph redline shifts to see if anything jumps out to anyone. I'll try to get some more logs and talk with ford see what they want to do. My closest dealer is understaffed apparently so I'm crossing my fingers and twisting my elbows

 

[luca1290]

The throttle never made these noises when I first got the car, I also tested this with other mustangs because at 2500-4000 the squeal makes it sound like a turbo with a bad impeller. When the noise is louder than my exhaust I start to worry

A little (perfectly normal) servomotor whirring is different from squealing so strong you can hear with the engine running, or I am missing something?

 

[KingKona]

The other cat is bad/plugged.

 

[Lunas Destiny]

How exactly do we share the hpl files from vcm suite? It says not allowed on here and I don't use Google drive. LTFT AND STFT were suspect to me in bank 2 but im not that good enough to really tell all that but I know when stuff makes frequencies its probably bad

The other cat is bad/plugged.

What makes you point to the cat? If that were the case then the fuel trims would be ALOT worse and I would notice less moisture from one side of the exhaust upon cold start. Both exhaust pipes produce the same amount of condensation at the same times which leads me to believe it is not a plugged cat. I am open to observations but please elaborate with reasoning.

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