GEN 2 Cylinder 2 misfire…swapped coils and didn’t move

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

91Eunos

Full Access Member
Joined
Oct 18, 2018
Posts
847
Reaction score
1,582
Location
Hill country, Tejas
Will run a compression test tomorrow when I can find my stuff after moving crap between garages, but in the meantime did the basics: swapped coils (twice), and still getting misfire on the same cylinder. Swapped plugs too, and misfire still on cylinder #2.

Have a new set of plugs, and will swap them too just because I’m in there, but honestly, the ones in there now have <15K miles on ‘em and look perfect; very light brown ash and no moisture/signs of oil leakage at all.

I guess it could be an injector or a loose/worn wire, and will run that to ground (heh, see what I did there?) if possible, but man, I hate chasing electrical gremlins if that’s what it is.

Edit: truck has 103K miles, has had cam phasers done (x3 LoL), and all major service performed by dealer. Zero issues other than cam phasers and IWE. Had one coil going out a couple years ago, but swapped out and replaced with a factory replacement.

Edit #2: only seems to happen when I’m at full throttle. If I ease it up to 80+ mph, there’s no issue at all; runs smooth. If I apply full throttle, the check engine light starts flashing, and the whole truck shakes…you can see the hood shaking like crazy! It goes away after a few seconds, and the check engine light usually extinguishes too. Same code every time: P0302

Any ideas from the hive mind?

@FordTechOne any input appreciated.
 
Last edited:

FordTechOne

FRF Supporting Member
Supporting Member
Joined
Jul 29, 2019
Posts
6,664
Reaction score
13,041
Location
Detroit
Will run a compression test tomorrow when I can find my stuff after moving crap between garages, but in the meantime did the basics: swapped coils (twice), and still getting misfire on the same cylinder. Swapped plugs too, and misfire still on cylinder #2.

Have a new set of plugs, and will swap them too just because I’m in there, but honestly, the ones in there now have <15K miles on ‘em and look perfect; very light brown ash and no moisture/signs of oil leakage at all.

I guess it could be an injector or a loose/worn wire, and will run that to ground (heh, see what I did there?) if possible, but man, I hate chasing electrical gremlins if that’s what it is.

Edit: truck has 103K miles, has had cam phasers done (x3 LoL), and all major service performed by dealer. Zero issues other than cam phasers and IWE. Had one coil going out a couple years ago, but swapped out and replaced with a factory replacement.

Edit #2: only seems to happen when I’m at full throttle. If I ease it up to 80+ mph, there’s no issue at all; runs smooth. If I apply full throttle, the check engine light starts flashing, and the whole truck shakes…you can see the hood shaking like crazy! It goes away after a few seconds, and the check engine light usually extinguishes too. Same code every time: P0302

Any ideas from the hive mind?

@FordTechOne any input appreciated.
Before getting too deep into it you’ll want to use a scan tool to monitor the fuel system PIDs. If the misfire occurs when the PCM switches from PFI to DI, you can be pretty sure the direct injector for that cylinder is at fault.
 

Hadlebfc

Member
Joined
Jun 9, 2024
Posts
10
Reaction score
0
Location
Canyon Lake, CA
My 2019 truck is at 40k miles and cylinder 3 is consistently going between P0303 P2306 or P0353. New plug, new coil and still doing that. Rechecked plug, coil, and wire connection and they look fine. It’s only happening once I Rev it hard too. Thoughts??
 

FordTechOne

FRF Supporting Member
Supporting Member
Joined
Jul 29, 2019
Posts
6,664
Reaction score
13,041
Location
Detroit
My 2019 truck is at 40k miles and cylinder 3 is consistently going between P0303 P2306 or P0353. New plug, new coil and still doing that. Rechecked plug, coil, and wire connection and they look fine. It’s only happening once I Rev it hard too. Thoughts??
You have DTCs for the primary side of the ignition; P0353 is Ignition Coil 'C' Primary Control Circuit/Open and P2306 is Ignition Coil 'C' Primary Control Circuit Low. These need to be diagnosed first; P0303 is just a conditional DTC from ignition issue.
 

Hadlebfc

Member
Joined
Jun 9, 2024
Posts
10
Reaction score
0
Location
Canyon Lake, CA
Hey guys I have my 2019 Gen 2 with 40k miles in a performance shop for more than a week and after multiple compression and leak down tests showing good they are recommending cam phaser replacement and telling me that alone won’t fix this issue so they also recommending top end rebuild!? I had the coil and plugs replaced prior to bringing to the shop. Could the Cam Phasers be the culprit here?? I don’t think a top end rebuild is necessary ..
 

The Car Stereo Company

aka grumpy car stereo guy and frf rolodex
Supporting Member
Joined
Jul 8, 2012
Posts
32,612
Reaction score
23,656
Location
here, on frf
Hey guys I have my 2019 Gen 2 with 40k miles in a performance shop for more than a week and after multiple compression and leak down tests showing good they are recommending cam phaser replacement and telling me that alone won’t fix this issue so they also recommending top end rebuild!? I had the coil and plugs replaced prior to bringing to the shop. Could the Cam Phasers be the culprit here?? I don’t think a top end rebuild is necessary ..
whats the issue?

and performance shop = upsale on stuff you dont need (a lot of times) cam phasers only if you need them. not all trucks are affected
 
Top