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What do these codes and OBD2 readings indicate?

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Thread Starter #2
Sorry, I'm new to this forum and somehow my text didn't carry into the post, here is the text:

Hello all,

A month ago I bought a 2017 ford fiesta 1.6l with 32k miles and not long after I got the dreaded P0303 and P0316 codes, engine misfire. I bought an OBD2 scanner, replaced the spark plugs and have driven perhaps 100 miles without seeing the code again. I'm not an expert (or even knowledgeable) on spark plugs, but spark plug 3 and 4 ceramic insulators were more white than the tannish look in spark plugs 1 and 2. I also noticed that the coolant level was low (not empty, but low) and filled it up in between the min and max level. After test driving it the next day I noticed the coolant level was a bit lower, maybe an inch, so I added in more coolant. Now I've driven it another 50 miles or so and the coolant level has not dropped. I'm hoping this was just a case of the coolant filling the rest of the coolant system, but I will keep monitoring the reservoir.

There was also a P1450 'unable to bleed up fuel tank vacuum' code in memory, but it was listed as archive (inactive), so I assume it has nothing to do with the misfire.

I've been driving it around and noticed that the long term fuel trim value is generally stuck at -7%, though it can fluctuate quite a bit while driving. It jumps close to zero with throttle open and then goes down to about -10% when coasting foot off pedal. I'm inexperienced with reading OBD2 data but I assumed the LT trim would not move as much as it is moving. Is this normal? My understanding is the computer has determined the car is running rich but when throttle opens it becomes less rich. Are these normal readings or should I suspect issues with the fuel system? I'm thinking about buying a fuel rail test kit just to verify the injectors are good.

I don't see any bubbles coming into the reservoir tank while the engine is running indicating a coolant leak in the engine. I tried pressure testing the radiator with an autozone loaner pressure test kit but they didn't have the right adapter for the reservoir and their universal adaptor just pops off when I pressure it up to 5 - 10 psi. I looked at the exhaust and it's clear, and I don't smell any coolant either in the engine or in the cabin.

I have an old CRT o-scope and my plan for tomorrow is to do a relative compression check and see if I can verify the compression. I don't have too high hopes on this test and may break down and buy a compression test kit.

I attached pictures of the spark plugs. I did notice that spark plug #3 has a line across the insulator, but I couldn't feel anything with my fingernail and I just don't think it possible to have disrupted the spark. The spark plug holes were fine, no oil or coolant in them, but the misfire and the low level coolant really has me worried. Before clearing the DTCs after replacing the spark plugs it stated there were a total of 31 misfires, all cylinder #3.

I guess this isn't much information to go on, my main priority is to assess the engine and make sure it's not toast. Anybody have any thoughts on this that could help me out?

Much appreciated!
 

Handy Andy

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#3
That "brown" is from the crack in-between the insulator, and the nut - the plugs were cracked, possibly during an install from the previous owner or even the factory. Age? Possibly, but might be more from changing plug wires if they got stuck on the plug when they tried to replace or remove them.

But these - if they are truly from the previous owner - these are not original FORD plugs which are SP-525 - but I can see if the OEM was IMPORT, as in assembled in Mexico or Brazil, they used their own native sources for these plugs.

Don't worry, they are SP-525 equivalents - but the installation or any sort of removal and reinstall - gives or raises questions.

Were the plugs ever pulled and regapped then installed and reused?

OR were these from a tune up done by a local shop using MOTORCRAFT cross references?

These look to be CYFS12YEC - which is a Motorcraft Part - but as Alternate to SP-525.

As far as heat range - they should be close to correct, you're having issues with the coolant - so the bubble part you would know by engine off and loosening the cap and watching it "deflate" from running with seeping from the combustion - and you'd also know by color that oil may have seeped into it by its ring it'd leave by the tank caps threads - if it is translucent and clean - then no, but foggy and thick - then yes - gasket issues.

1662083560080.png
This is from one of my work vehicles.
Old fluid, has some staining INSIDE the tank
You can see the bleed down, weep hole towards the top of the photo
for the excessive pressure and fluid to escape - but the
discoloration is noticeable and dark.
Should be flushed out.​
  • How would you know?
    • Unless you know what to look for, it's hard to know - but a dark color usually indicates that the fluid has been exposed to high heat - using up its additives as well as "washing out" the core of the jacket the coolant flows thru. So, the foaming from low coolant and hot cylinder head - is what you see around that plastic - it's under and inside the tank.

Back to the plugs...

The threads are showing dark discoloration - so overheat is a serious thing to think about. They used oil to keep from seizing - but that is not the only reason for that discoloration - looks like some hard use from previous owner and hot conditions too. Highway miles? Stop Start traffic? Each can add its own share of character in this, so the plugs show heat - the coolant is low - showing evaporation possibly from boiling and/or lack of attention - but to have it topped off and stable - you now have some normal use left in it.

So, they used plugs properly cross referenced, but the dark brown ring on the insulator usually means an arc or seal fail - which you would know by how the thing would hesitate in specific conditions. Heat is also a factor but would affect ALL plugs the same way.

The Firing Order is 1-3-4-2 so the plugs seem ok, the end ones - Electrode tips have a minor ash collection with little residue - plug 3 tips is clean and in good condition. But is also confirms the issue of overheat, hot plugs and the insulator fail. You're trail of codes leading to #3 - is also a contributing factor in this diagnosis.

To help - Plug 4 is towards the Tranny side but Plug 3 is just under the EVAP hose and purge lines for Brake Booster and IDLE air quality - so the LEAN condition of Plug 3 - shows something taking us back to the EVAP code of a bad gas cap seal or tank seal fail - or even a hose pinching and blocking of purge, or the nylon hose from the EVAP purge valve - cracking and letting air in - generating a LEAN condition.

Have to stop for supper - look this over and see if we need to get specific.
 
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Handy Andy

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#4
There was also a P1450 'unable to bleed up fuel tank vacuum' code in memory, but it was listed as archive (inactive), so I assume it has nothing to do with the misfire.
Heres' a copy of the TSB

1662116024024.png

This is a reprogramming for the "calibration" so they kept the DTC in there but more for a reminder.

So you should run the VIN at a dealer to see if the FORD sites have already run this VIN thru an upgrade or version revision - it's buried in the code, so they'll have to dig up the revision used for the latest updates and should give you a clue to what is going on in that "Starred off" code.

Before any one jumps, the issue is dated, so the problem then lies in specifc dates - where the flash program may have affected more than one type of vehicle for that revision.

The vehicles may be dated for say 2017 model year, but the MANUFACTURED date of the individual sub pieces and units that go into it, are from the past (Previous) years of manufacture - if any of my own experiences with a 2018-2019' on a closeout amortizing year has shown (2018 parts?) - my vehicle was a hodge-podge of closed out parts from previous model years used up to finish the line. OR the assembly results from at least some very angry workers known this was their last year to work there
 
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OP
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Thread Starter #5
Handy Andy, thanks for the detailed reponse! I've been researching and wracking my brains thinking about what all problems are wrong with this car that I needed to get someone else's opinion to ground my thinking. What you wrote is very useful to me and gives me something to think about.

You are right, the car was manufactured in Mexico and the spark plugs are CYFS12YEC spark plugs and they were gapped at .030, .034, .034, and .034. Could these be original since it was manufactured in Mexico? They appear to have seen some usage.

When I took them off both the plug wires and the plugs came out fairly easily, I had no trouble removing them. I replaced them with new spark plugs and gapped them to .030, and they seated and torqued easily as well. I did notice the brown staining both above and below the seating nut of spark plug #3. I agree about the clean look of plug #3, the ground electrode is definitely whiter than the others at the tip indicating it was seeing something different. I've researched and people say clean looking spark plugs can be an indication of a coolant leak.

This and the low coolant are what have me really worried about a coolant leak. My only idea is to continue to monitor the coolant and see if it stays level. I suppose the definitive way to find out would be a leakdown test, but I'm not sure I could get each cylinder to top dead center by myself. I'd have to enlist someone to come and give me a hand with that.

I figured the dark discoloration on the threads was not a good thing, but I have removed spark plugs that look like that and just chalked it up to drops of oil getting on the threads over the thousands of miles they were driven. Those were cars with a lot more miles on it than this one. This is a manual transmission so that was a concern. It seems a lot of people use manual transmission cars like they're race cars, even though this car is nowhere close to something like that.

On the coolant, stupid me, I added the 'all vehicle' coolant to top it off so I believe the color has been changed. I'm going to flush the coolant and put in the proper coolant in the next few days, and then continue monitoring.

Unfortunately I don't have any knowledge about the previous drivers or how it was driven. I did pull the car history on it and there was nothing indicating serious issues, but who knows how accurate that was.

On the P1450, my engine is not an ecoboost, do you think that would apply? It seems like they would have different firmware for the 1.6l ti-vct.

Speaking of the ecoboost engine, I have read where they had problems with the engine and blow-by gasses fouling the valves and such, would that also apply to this engine?

I just looked at my reservoir on cold engine and it may be 1/4" lower than when I filled it. Ugh. I took a picture of the level and will continue taking pictures to verify. If there is a coolant leak, hopefully it's 'only' a head gasket.
 

Handy Andy

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#6
The ECO boost motor demonstrated the issue of gasket warp or deformation while under load and if severe enough can blow gaskets. Too much intake-charge of air can cause the compression ratio to go beyond initially planned.

The TSB was from the EVAP system and its need to find vacuum in situations of low vacuum affecting draw of fumes for emission control. Turbos generate boost.

This is not unique to the turbo'd engines - happens even on NA's so the deformation and blowby from compression weakens the gasket and eventually will make them fail.

As far as level - take note of ambient air temp so you can find that cold motors versus hot or warm days - will affect coolant levels too.

Just to add some thoughts...

Right now, as I was re-reading this thread, I also took note of this...
A month ago I bought a 2017 ford fiesta 1.6l with 32k miles and not long after I got the dreaded P0303 and P0316 codes, engine misfire. I bought an OBD2 scanner, replaced the spark plugs and have driven perhaps 100 miles without seeing the code again.
I want to stop here for a moment...

This is a 2017 Fiesta - it's (over) 5 years old now, and with only 32K miles - those two codes?

P303 - read this carefully (From Engine Codes site) - you wanted to know about the plugs...

1662387222179.png


and also includes the P0316 code which is more serious

1662387365848.png
To help you understand this...

Your plugs - 3 of them are seemingly ok, but one is not - number 3 on cylinder #3.

That is the one with the "ash" and less use, which if the above codes are correctly identified by the vehicle PCM - then that means that the engine ran LEAN in an attempt to prevent catalytic converter damage.

1662549310327.png

To have the above happen at 32K miles, makes me wonder how this got so wrong - so fast?

So, is the car actual 32K miles or are we looking at a rescue?

The plugs show overheating, the codes show misfire and then subsequent LEAN condition (intentional injector shutoff forcing lean condition on 1 plug) on cylinder 3 so the other 3 injectors and their plugs had to take up the difference. It would explain the darker fouling (carbon left behind of a RICH fuel condition washing the cylinder) but what caused the initial overheat code? (If there was one?)

Reasoning is this - the EVAP P1450 code was part of a system programming issue - meaning that the vacuum in one condition, that result is not the same as in another condition...

1662388110487.png

In the above wording - there are two events that this code shows up when they don't agree.

The keyword? Not at Idle

So, this may indicate long idle, overrev - high speed driving - "rental car - Rent-A-Wreck" driving conditions.

Long idle with highway or high RPM activity and deceleration - generating high-vacuum during specific engine running times and long idle waits.

Sound familiar?
Like this?
1662388477457.png

For you to get this car - an S model - with only 32K miles might have been subjected to a lot of abuse by previous owners.

Might want to run the VIN and see whom - all of those - owned this vehicle before you.

To have low miles yet high temp overheat condition and the "galling" of the threads - there is oil on them, but their threads - much of the exposed threads are dry, not wet, shiny more like a varnish and if you look carefully - there are areas of thread that show LACK OF oil as a varnish but show another type of seizing or galling that happens when the plugs are subjected to high heat.

Where the "Varnish" the oil on that section of thread - released from the side of the cylinder head - so it accumulated on the threads of the plug - that's that "dry" part - when you removed the threads, that backing out - unthreading - released some of the dirt collected onto the threads of the plug and stuck to it threads instead of falling in or adhering to the cylinder head threaded side.

Which raises the question of "are these for real"? Then, that answer - if it's true, the vehicle was subjected to a lot of heat during the 32K miles before you got it to get to this point - on top of the fact, that the Plug 3 was damaged to a point of misfire during this time, before you got it; and if that, for how long?

Couint your lucky stars you rescued this one from an early demise.
 
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OP
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Thread Starter #7
Hey Andy, thanks for the response, I read it and will have to re-read it a few more times to let it sink in. Your part about the mileage got me to thinking, when I bought this car I downloaded a free car report and it said there were two previous owners, but didn't give any info on approximate mileage. Today I downloaded a $20 report from carvertical.com and in it there is a section for approximate mileage. It is a line chart with dots between 2017 and 2022 and the mileage ends at 119,037 in August of 2022 - I bought it on August 5th. Well, needless to say, I am feeling like I've been scammed at this point and went down to verify the odometer and yes it still reads 32k miles. At least I didn't misread the odometer.

I sent an email to carvertical asking where this mileage comes from and am awaiting their response. I also downloaded a report on my other car that I bought new in 2014, it was fairly accurate and it looks like the mileage dots lined up with either tire service or insurance renewals. Unfortunately the car report I received for the fiesta doesn't list previous owners and I am still waiting on the title from the used car lot that I bought it from. I'm thinking I may not ever get it.

If it has 120k actual miles it doesn't look like it. There are no suspension squeaks and rattles, interior and engine compartment look clean and not overly used, and everything works. But I could have been fooled.

Speaking of which, I changed the oil and there was a definite gasoline smell to the used oil. I didn't look brown or milky like there was coolant in it. I also changed the oil in my other car and it also had a gas smell, thought not nearly as strong.

I also got a compression gauge and tested all the cylinders:

Cyl 1: 125
Cyl 2: 140
Cyl 3: 127
Cyl 4: 125

From what I understand each cylinder should be in the 140 - 160 range? If so those numbers don't look too good. I think I'd feel better if they were all around 125, but cyl 2 sticks out like a sore thumb. I can't blame it on a low battery with that one in the mix.

Before I did the compression test I was thinking it might be a leaky fuel injector and was going to pull all of them and check the sprays to see how much of a mist they output. I did check the resistance and they are all at 14.5 ohms, so I'm thinking that if there's anything wrong with them it will be on the mechanical side and not the electrical/solenoid part. There is one hose going from the front of the valve case to the bottom of the air filter box that is really hard to get off though, and I don't want to damage it. The hose clamp comes off, but the hose itself is on pretty tight and the hose is stretching without releasing. I guess I'll work on it with some pliers tomorrow. Do you know what that hose is? I might need to order a replacement after I'm done with it.

I think my next plan of action, aside from possible legal which won't amount to anything except lawyer fees, is to test and clean the fuel injectors and then do a leakdown test to try to isolate where compression is failing. With three cylinders I'll wager it's failing everywhere. I also was going to take out the thermostat and do a thorough flush of the coolant, but right now I think I'll leave the thermostat in there and just use distilled water, let it heat up and then drain it a couple times before adding back in the right coolant.

"So, this may indicate long idle, overrev - high speed driving - "rental car - Rent-A-Wreck" driving conditions. Long idle with highway or high RPM activity and deceleration - generating high-vacuum during specific engine running times and long idle waits." - This is what I am afraid of with this car. I was hoping the fact that it is a manual transmission would mean that rental car and rent-a-wreck companies wouldn't touch it.

"Count your lucky stars you rescued this one from an early demise." Haha, this car is going to send me to an early demise!
 
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Thread Starter #8
The yellow circle is the hose I was talking about, it appears to be a vent hose going from the valve cover to the air filter box?
 

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Thread Starter #9
Here's the mileage section of the vehicle history report. It appears that the odometer checks were done regularly up to the point just before I bought the car. I sent an email to carvertical to get clarification on how they obtain mileage data, but I'm thinking it's legit. I just sent an email to my state AG office to see what they can do about this and as soon as I get a response from carvertical I'll be contacting the used car dealership.
 

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Handy Andy

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#10
Nice research!

How can it show 32 K miles?

Wow!

This seems to be ongoing problem.

To help on another question...

The circled area is the top breather line for the PCV system.

The PCV valve is just below the intake and uses a hose from it to the intake manifold, that upper hose lets air in from the airbox to "breathe" and keep the system at a slightly negative vacuum to help purge the crankcase of foul air and help the seals and gaskets last longer.

It uses a special clamp with tangs that when squeezed together the tab of one side meets the hole in the other, letting it lock in this open loose state so the clamp can slide on or off the hose to fit the hose onto the port at the valve cover.
 
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