Misfire under WOT

[Vallee]

How did you verify the grounds are good?

alright, I didn't do resistance check across all circuits but I did verify all ground points are getting good connection to the chassis. The wiring harness is basically untouched, it ran fine on the old engine the only difference is now I have a painted engine bay and I had to clean the connection points see photos attached.

At this point I'm almost convinced it is a fuel problem because when the engine starts to misfire my wideband reported lean 16+:1.

Fuel pressure seem to hold study though so I'm not sure exactly. I'm going to change the fuel filter pull the fuel rail check all injectors.

It's getting old fast...

 

[Gabe]

Back in around '04-'05 I was a Lincoln-Mercury service writer, had some Town Cars come in for hesitation issues, techs drove the cars, thought it was transmission issues, sent cars to our Ford store, their techs replaced fuel pumps, cars were fixed.

So how old is your fuel pump?

 

[Vallee]

Back in around '04-'05 I was a Lincoln-Mercury service writer, had some Town Cars come in for hesitation issues, techs drove the cars, thought it was transmission issues, sent cars to our Ford store, their techs replaced fuel pumps, cars were fixed.

So how old is your fuel pump?

Fuel pumps were installed in 2010. they're GT500 fuel pumps. It really feels like a fuel issue I wonder if some dirt found their way in the fuel rail and then in the injectors. When I took the engine out and had the engine bay painted the fuel lines were exposed and I am now wondering if some crap got in there and then found their way into the injectors? These plugs have about 15 miles on them.

 

[RocketcarX]

Open the plug gap and try again .035-.037
You would not have the AFR you do with a fuel problem

 

[Vallee]

Alright, I've uploaded a video of the misfire event under a steady 55mph cruse at around 2600 RPM. Near the beginning of the video you will hear some minor skips then it goes in full on fail-safe mode at about 3/4 into the video. You can hear an audible difference in the exhaust note.

 

[Vallee]

Here's a freeze frame code I retrieved from the incident...

 

[RocketcarX]

Open the plug gap to .035-.037

 

[Vallee]

Folks,

It’s been a while; I wanted to post an update...

I spent the last few weeks inspecting and replacing a bunch of components that I thought might contribute to the misfires. I even pulled the catalytic converters and inspected them (they looked like new). Nothing I did seemed to help... As you know, I’ve also been working closely with Lito regarding my misfire issue. Lito had an idea; and he proceeded in writing me a“test” tune and then asked me to try it out and see if I could replicate the misfire. Lo and behold; I loaded the "test" tune and tried to replicate the misfire but couldn’t!! Not sure what exactly he did, but not only did it eliminate the misfire is also made a noticeable difference (improvement) in how the car ran. I am now on to tune revision #6. And let me just say, the car is turning into a fun beast to drive! We still have some more logging and remote tuning to do but I feel we are getting close.

With that said, I want to give open recondition and a huge “thank you” to Manuel Pazo (Lito) - I would not be where I am without his help.. The man is a true genius.

Here is a link of the most recent remote log run.. enjoy...

regards,
Adam Vallee

 

[Pentalab]

I wonder what Lito did to correct the issue ? What ever it is, Hopefully he has taken notes on it, for future reference.

 

[Gabe]

So it was a tune issue the whole time?

Yaaaayyyyy .....

 

[EBABlacknChrome]

Sounds damn good and seems to be running pretty smooth.

Sent from my SM-G930V using Tapatalk

 

[Vallee]

Sounds damn good and seems to be running pretty smooth.

Sent from my SM-G930V using Tapatalk

Yes, very smooth.. power comes on strong and the RPMs pick up really fast..Lito just sent me a revised tune, made some minor corrections and added more timing... I think this build is going to be a beast. I am so happy I got beyond the misfire issue.

 

[travelers]

So it sound like your happy with the new tune. Glad that's working out for you.