I guess I spoke too soon. My wife's '17 2.3L EcoBoost Mustang is misfiring again. It has 146k miles on it, and the transmission is a 6R80.
It's throwing the same code, P0301. Per my wife, her car started running rough for 10 seconds before it smoothed itself out. I swapped the coil from cylinder 1 and put it on cylinder 2's spark plug to see if it moves. It didn't move.
Before I swap fuel injectors, per the dealer, her car was also throwing a P018C code, Fuel Pressure Sensor 'B' Circuit Low. I don't have any evidence of this myself, but I don't have a dealer level scanner.
I would check and see what low side fuel pressure the computer is reporting. Apparently these sensors can fail and report 0psi with key on.
@imperator That would definitely make sense as to why her car seems to occasionally misfire on start-up. I watched that video you sent, that guy seems to have a pretty fancy scanner.
it is a high end scanner, but it may not be required to just display fuel pressure.
@imperator I looked a little more into it last night. Apparently with her car, the check engine light will not come on if that particular component is messing up. I have an Innova 3100RS and I guess it's not powerful enough to diagnose this kind of thing. The check engine light not coming on when this fails is kinda ridiculous.
Well, my wife's head gasket completely blew this morning.
Maybe she missed her morning coffee? 🤔
I went to AutoZone and rented a head gasket tester, which confirmed my suspicion. The fluid turned from blue to green after a couple minutes
Oh, the car! 😦
Looks like a fairly involved job to pull the cylinder head:
Cylinder head specs:
Installation:
I've done R&R jobs on cylinder heads in the past but not on anything that modern. (Be prepared for at least some exhaust manifold studs to snap off.)
@chucktobias That's funny about missing her morning coffee. She doesn't like coffee, though. She was waiting on some guy who had an invalid card to get into the Wright-Patterson AFB. She's currently a contractor for them.
She noticed the coolant temperature started rising past operating temperature and she messaged me about it. I told her to turn the car off immediately to try to save it from blowing. It was already blown.
I'll let the mechanics we've used for years handle it. I'm way not up to snuff on replacing a head gasket on an EcoBoost engine.
I don't think I'd try that job on an EcoBoost engine either. The ones I've done have been old-school engines without stuff like turbos or variable valve timing.
@chucktobias I guess on the plus side, if you could call it that, the head gasket turning green should mean it's not seriously blown. Usually when head gaskets blow chunks clean out of themselves, the blue in the head gasket tester turns yellow almost right away. There was no coolant in the oil, either.
It was already blown.
aww that sucks. And kind of disappointing on a 150k mile engine. Do you think it's a result of it being a turbocharged 4cyl engine trying to accelerate a 3500lb vehicle?
I'll let the mechanics we've used for years handle it.
Do you think it'll be worth fixing?
@imperator It's been a great car other than those stupid purge valves going bad. She drives 28 miles one way for her commute every day, and she's maintained her transmission well.
She drives on the highway mostly.
She mentioned the other day when she was driving my V6 Mustang that it doesn't have as much get-up at low speed like hers does. I told her that's what happens with a naturally aspirated engine. Peak torque in my Mustang's engine is at 4k RPMs, vs 2500 RPMs in hers. When she drove mine on the highway while I was working on her car, she told me she manually downshifts a gear getting on the highway so there's more of a sensation that she's getting pulled back in her seat. I said that's torque. Haha.
She's an electrical engineer and has minimal clue on how engines work. I have minimal clue how electronics work despite having had a circuits class in college, so we go hand in hand.
Apparently, Ford's 4-cylinder EcoBoost is quite prone to head gasket failure
I'm reading that as well ( https://www.motorreviewer.com/engine.php?engine_id=135), but apparently it was an issue with the Focus. They put the wrong (Mustang) head gasket on them which had different coolant passages. "Mustang didn't have the problem with coolant leakage through a head gasket."
The check engine light not coming on when this fails is kinda ridiculous.
you're not looking for DTCs. You're looking for live fuel pressure data.
@imperator My scanner doesn't have that capability, unless I'm supposed to be looking for short-term fuel trims. The pressure sensor is located at the back of the engine, so it would make sense that when that sensor starts failing, the fuel pressure in the cylinder farthest from the sensor would be the first to go awry.
you need to get a pressure gauge or decent scanner hooked up to that car. Ideally before replacing parts.
@imperator Yeah, I know. I'll get a fuel pressure gauge at AutoZone either later today or tomorrow.
I replaced the low pressure fuel sensor last night per what that Ford tech said over the phone the other day. It did not solve the problem. From what I read online, any scanner can pick up the trouble code and the code illuminates the check engine light, I just can't analyze it very well without the proper scanner. If anything, it actually made the start-up slightly worse. I used a Motorcraft part.
Short-term fuel trims were +1.3% and long-term fuel trims were 16% after the part change.
Well, my wife's head gasket completely blew this morning. That's what was causing the misfire on Cylinder #1.
A friend of mine and I replaced the water pump after we noticed it was leaking and we fully bled the system afterwards. (The dealer "mechanic" noticed grime, and he only said that "something was leaking"). He didn't offer to replace what it was. That was what alerted me to a coolant leak.
The dealer mechanic was more concerned about a flex pipe and all that excessively expensive jazz. That's a "stealership" for you.
When we replaced the water pump, the old water pump gasket was stretched probably 2" farther than "normal". A week ago, when I was adding some coolant to her car, I noticed a tiny bit of sludge on the radiator cap. It wasn't there on my Mustang. That was a red flag.
I went to AutoZone and rented a head gasket tester, which confirmed my suspicion. The fluid turned from blue to green after a couple minutes 🙁
I looked a little further into what happened to my wife's car today. Apparently, Ford's 4-cylinder EcoBoost is quite prone to head gasket failure at around 150k miles, even with taking proper care of the engine. Ford redesigned the 4-cylinder EcoBoost when they noticed engines were failing due to a flaw. The coolant passages are too close to the combustion chambers for a turbocharged engine.
Ford's engineers likely also redesigned the engine to be capable of both ordinary fuel injection and direct injection to take care of the original EcoBoost's inability to wash fuel over the engine's intake valves. I believe that started with the 2018 refresh, when Ford scrapped the 3.7L V6.
Do you think it's a result of it being a turbocharged 4cyl engine trying to accelerate a 3500lb vehicle?
Ford produced 4-cylinder Mustangs in the 1980s and they were fine. They were of similar displacement to hers. With the turbo, though, you have to get the cooling jackets and oil journals in the right position or you're going to have problems. I think the concept of the engine was okay for what it's hauling, vs a 2.7L turbo powering a full-size truck and weighs 5,000 pounds, not counting any cargo or trailer. Small turbocharged V6s in full-size trucks are just a disaster waiting to happen, in my opinion.