• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!


Miracle My Engine Didn't Blow Up

Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
#1
My ST has been running pretty crappy for a couple weeks. Misfiring under anything over 50% acceleration. But overall running fine under normal driving conditions. I've been telling myself that it's probably just a bad batch of E85. Three fill ups later, still behaving that way. Getting annoyed, I haven't had my power in a while I gave her the beans on the freeway today easing into it. It actually went well and pulled like a champ, I was thinking OK! Here we go, it's better now. As soon as I let off the gas it started to misfire terribly and didn't stop. There was no where to pull over it was down to 2 lanes construction so I had to drive it about 3 miles like that (felt a part of me dying every second). Last week I did an oil change and decided to take a look at the air box... See picture. Obviously not good. Figured I had been running rich as not enough air was coming through and maybe I fouled a plug or two. I got off the free way and there was an AutoZone right there, got 6 plugs, adequate tools in truck already and I swapped all 6 plugs. See the issue?? Thank god that piece(s) didn't go through and grenade my motor. Two hours later, and a few scratched knuckles it fired right up, cleared codes, idled for about 20 minutes, took for test drive, no codes, no misfire, all the power back! Someone was looking out for me today!
 

Attachments

GearHead_1

1000 Post Club
Messages
1,555
Reactions
1,298
Points
262
Location
Utah
Vehicle
Exploder
#2
I think you should buy a lottery ticket. I can't believe that went out an exhaust valve and through a turbo without damage. That's amazing. I'd probably do a leak-down test on it just for grins and giggles. I'd stick a camera in the cylinder and if I could find the motivation, I'd take a look at that turbo too.
 

Last edited:
OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #3
My only reasoning is I was off boost and it went out the exhaust. If that hit a impeller it would have grenaded for sure.
 

UNBROKEN

4000 Post Club
Messages
4,580
Reactions
5,355
Points
352
Location
Houston, TX, USA
#4
I would have bore scoped that hole at a minimum. Looks like you lost the ground, center electrode and insulator….they didn’t just evaporate. If they made it past an exhaust valve without damage they didn’t make it past the turbine wheel without smacking something. It doesn’t take much to throw a turbine out of balance.
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #5
Cylinder walls and piston head almost certainly is not good lol. I didn't put my scope in because I want to will it to be OK. Didn't even put my magnet down there to pull scrap. But Holy hell it's back to my 500hp beast I'm used to and I'm so happy. Lotto ticket? This is hitting the lotto.

Side note I'm going to say anyone else running e85 should change plugs every 2 oil changes. That was 3 for me and was smoked.
I think you should buy a lottery ticket. I can't believe that went out an exhaust valve and through a turbo without damage. That's amazing. I'd probably do a leak-down test on it just for grins and giggles. I'd stick a camera in the cylinder and if I could find the motivation, I'd take a look at that turbo too.
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #6
I would have bore scoped that hole at a minimum. Looks like you lost the ground, center electrode and insulator….they didn’t just evaporate. If they made it past an exhaust valve without damage they didn’t make it past the turbine wheel without smacking something. It doesn’t take much to throw a turbine out of balance.
I would feel it for sure if a turbo was off. They spin at ridiculous rates. They would implode if off even a little. I really think I just got lucky as hell.
 

GearHead_1

1000 Post Club
Messages
1,555
Reactions
1,298
Points
262
Location
Utah
Vehicle
Exploder
#7
Like I said if you're that lucky, you need to buy the lottery ticket. I can't believe there isn't damage in there waiting to deal you aces and eights.
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #8
I have driven about 3 hours today after repair and no issues. Car gods have blessed me. It is the Woodward DreamCruise today here in Detroit so maybe I had someone watching out for my motor in spirit form.
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #9
Number 5 is easy to get to, which was the plug in discussion. Maybe I'll scope it this week if enough people get on this thread and pressures me lol. Don't want too jynx my fortune though.
 

Messages
121
Reactions
35
Points
27
Location
Amsterdam
Vehicle
Ford Explorer ST PHEV MY22
#10
Number 5 is easy to get to, which was the plug in discussion. Maybe I'll scope it this week if enough people get on this thread and pressures me lol. Don't want too jynx my fortune though.
You definitely got lucky!

But i wouldnt push that luck either

Perhaps there is some damage and the sooner you'll know, the better, so it won't lead to more damages.
 

TMac

1000 Post Club
Messages
1,706
Reactions
1,494
Points
262
Location
Knoxville, TN
#11
Your engine will not "run rich" because your air filter was dirty, although a filthy filter will impact performance.

You had better have that cylinder bore-scoped. I cannot see any way that amount of material exited via the exhaust valve and turbine without some damage. Most likely that garbage is still in the cylinder.
 

FORZDA3

Member
U.S. Air Force Veteran
Messages
489
Reactions
326
Points
67
Location
Gloucester, VA, USA
Vehicle
2021 Explorer ST
#12
What’s left of the metals that weren’t vaporized are probably imbedded into the piston top. The ceramic was pulverized into small enough pieces to pass through without significant damage.

You may have an injector clogged or otherwise not spraying enough fuel in that cylinder. Lean causes plug destruction, not rich. Or you may have installed a bad plug.

You’re lucky all right, but almost certainly not damage free. If you look, you will see the damage. It can run great for a long time with dents and dings in the head and piston top.
 

Messages
219
Reactions
87
Points
27
Location
Jessup, MD, USA
#13
You did the 5 cylinder mod!

I've seen this happen a surprising number of times on the Focus ST (2.0 liter ecoboost) and I can't recall any catastrophic results. Usually everyone gets lucky. I was in the same situation recently as my cylinder #4 spark plug electrode disappeared and the car was only running on 3 cylinders.

I replaced the plug and it's been fine for several months now.

I'm wondering if these motors somehow create a condition that can make the electrode tip simply liquify and melt, instead of breaking off and destroying everything. I've just seen way too many cases of people getting lucky.
 

Blue Beast

1000 Post Club
U.S. Army Veteran
Law Enforcement
Messages
1,574
Reactions
620
Points
262
Location
Cincinnati, OH, USA
Vehicle
2020 ST
#14
I had this happen to a Pontic G6 my daughter was driving, and we had to replace the engine. It completely destroyed the one cylinder and engine.
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #15
Well I drove 2.5 hours away on a trip and same thing happening, misfire city. Changed 5 of the plugs (all but #3), all looked good and didnt change the outcome. I stopped after I slipped and broke a vacuum nipple off the charge pipe. So waiting on a very expensive tow home to rip it apart this weekend and find out what's going on. Sadness.
 

Cruising68

1000 Post Club
Messages
1,620
Reactions
1,181
Points
262
Location
Chicago, IL, USA
#16
Well I drove 2.5 hours away on a trip and same thing happening, misfire city. Changed 5 of the plugs (all but #3), all looked good and didnt change the outcome. I stopped after I slipped and broke a vacuum nipple off the charge pipe. So waiting on a very expensive tow home to rip it apart this weekend and find out what's going on. Sadness.
Bummer for sure. I’m checking my plugs at 20k just to play it safe. Had to be something strange going on


Sent from my iPhone using Tapatalk
 

TMac

1000 Post Club
Messages
1,706
Reactions
1,494
Points
262
Location
Knoxville, TN
#17
Well I drove 2.5 hours away on a trip and same thing happening, misfire city. Changed 5 of the plugs (all but #3), all looked good and didnt change the outcome. I stopped after I slipped and broke a vacuum nipple off the charge pipe. So waiting on a very expensive tow home to rip it apart this weekend and find out what's going on. Sadness.
By any chance did you pull the codes- I'd be looking for "P" series misfire codes, and possible something else related to the cause?
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #18
Of course. Misfire 3 5 6. I suppose there's a chance there's an issue with number 3 plug. But either way something bigger is wrong if I'm buying plugs every other week. I'll update this weekend when I tear it apart.
 

TMac

1000 Post Club
Messages
1,706
Reactions
1,494
Points
262
Location
Knoxville, TN
#19
Yeah, something bigger is wrong! Since you have the Nostrum parts, any chance you've logged fuel pressure?
 

OP
D
Messages
189
Reactions
95
Points
27
Location
30122 Woodward Ave
Thread Starter #20
I have not but I will be turning to this thread for the consensus of tests I should do to rule out what's wrong. Plug, coil, injector, or something worse.
 



Top