2016 Edge 3.5L Multiple Misfire under hard accel

[JerrettH]

Hi, new member here. We had a 2011 Edge that treated us great so we traded for a brand new 2016 3.5L Titanium AWD a few years ago and it was built on a Friday I think.... Anyway for this specific issue my wife was passing on the highway and the cel blinked under acceleration. Codes were 0300, 0303, 0304. We only have 57,000KM (35k ish miles) on it. I replaced the spark plugs, cleaned the TB and noted a lot of oil in the plenum so I changed the PCV/cleaned the plenum as well. We have run injector cleaner through it now too. When changing the plugs I moved the coil pack from #3 to #6 so if I had to change those 2 coils it wouldn't require taking the plenum off again. 

 

When test driving now I can recreate the flashing cel by sticking the accelerator and the cel will flash when the engine redlines, if I immediately slow down I can feel the engine vibrating from the missing. The cel stops flashing and does not illuminate but it stores the same the 3 codes which seems strange since the cel turns off after the flashing. Previous to the plug replacement it would stay illuminated after the flashing. So moving the coil didn't move the issue but something changed the cel behaviour. I am leaning towards injectors but with such low km on the car I am kind of baffled it only happens at redline if I accelerate hard and stop before it hits 5.5k ish rpm no cel flashing. We haven't used it a lot with covid as we have 2 vehicles.

 

Any suggestions other than maybe swapping injectors and seeing if the problem moves cylinders? Thanks!

Edited July 13, 2021 by JerrettH

[WWWPerfA_ZN0W]

Wow, first case on the gen 2 3.5 I have heard of problems like this, and at such an early mileage.  But it HAS been 5+ years, and with only 35K miles on it, I would say it is WAY under-run. The only reported problem has been a throttle body issue in the 2015MY.

 

Any codes at this time? Which cylinder is setting the misfire (you can check with Forscan Lite PIDs or Mode 6)?  What was the plug gap on the old plug(s)? Were they fouled at all or did they have the normal light coating on them? Were the threads oilfree?

 

Sounds like a possible PCV issue, but if the engine was run under special operating conditions as the mileage would indicate, I would switch to a full synthetic SP rated oil, maybe even step up to 5W30, to lower volatility and give the engine a more forgiving environment.

 

[JerrettH]

The codes now are the 0300 multiple misfire, 0303 cyl 3 misfire, 0304 cyl 4 misfire, same as before but the cel doesn't illuminate just flashes when redlined then turns off even though the codes are pending when I scan it after. The plugs were pretty fouled, not the light coating some chunky bits on them and the threads were oily/carbon plugged. We typically put about 10k kms on a year but covid slowed it way down as we both ended up unemployed and not going anywhere so it is definitely under used. I haven't gap checked the old plugs but they looked fine gap wise just dirty, will do that today. The PCV seemed to be allowing alot of oil into the plenum so I replaced that while I was back there. 

 

I am going to get a tank of fresh fuel today and take it for another drive to see what happens now that the injector cleaner has been run through there.

[WWWPerfA_ZN0W]

sounds like a plan.  flashing CEL has only one meaning: misfire.  steady CEL means there are other major problems in the works.  So at least you have made progress!

 

how does the throttle body look?

 

sorry to hear about your situation, hope things look up for you very soon.

[JerrettH]

Thanks, the throttle body was covered in caramel oil deposits on the plenum side and just some light soot on the air filter side I’m assuming from the air tube off the front valve cover. 
 

I cleaned it up but not much you can do with these electronic ones it seems. Haven’t been able to take it for a drive yet will update on how a fresh tank of fuel goes. 

[WWWPerfA_ZN0W]

yeah definite pcv issue.  haven't seen a mention on Ford bulletins.  you MAY need to install a catchcan if moving up to a better oil does not resolve the situation.  there were some 2011-2013 MY edges that needed a revised valve cover for oil in the intake, but not a peep on gen 2+.

[JerrettH]

It’s such a strange issue now. With the fresh tank I can accelerate just fine even semi aggressive and there are no problems. 

 

But if I put the pedal to the floor from a stop the car accelerates, hits redline ish rpm 6000+ according to the tach,  then shifts to second I’m assuming. At this point there is no problem but if I keep my foot into it the engine redlines a second time, shifts up again and that’s when it flashes the cel/starts misfiring. So it only misfires under load and at the exact time it shifts to a higher gear, it hasn’t happened on the first redline/shift in a bunch of test runs always the second shift.
 

I realize it’s not normal to be out redlining the engine repeatedly but this is the only way to duplicate the issue that I have found. Went for a drive on the highway today over 60 minutes and no issues under normal conditions. The cel also wasn’t on after all this it just flashes and goes away. 

[enigma-2]

I was reading on the 150 forum where another guy fixed this with a new battery. (He figured the coils on two cyls were weak and blowing out under load). Another guy said his dealer reflashed his PCM. Another removed his high octane  tune and it stopped. And another the dealer lowered his red line. 

[JerrettH]

I can believe all of that as we thought we had it narrowed down to only when we redlined. I was unable to get it to flash for a day so we took the car for a 3 hour round trip and it happened when passing at 4100 rpm so no where near redline.
 

That was about 30 minutes into the trip and it didn’t have another code after that in 2.5 more hours of driving.
 

It’s going to be something really strange when we figure it out I think. I’m tempted to play musical fuel injectors just in case I can get the codes to move cylinders that way now and rule out another item possibly.