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P0420 Code & Oil Overfilled

Boomerstoys

Keep the shiny side up & the rubber side down!
Hope some of you can help me out with this. Yesterday, I head out and get on the freeway shift to 6th, and BAM---check engine light! Car is running fine, call the dealer and head there. They hook up their code reader and find a P0420 code, cat inefficiency bank one. WTF!
I had previous problems with misfire codes when I ran Laguna but codes were P0300, P0301 and P2626. Short version, when I got back to Seattle, my dealer found that the O2 sensor wires were pinched and burned when they replaced the transmission!
This p0420 code is really surprising since I run Chevron 92 octane or Shell V-power 92 octane. Exhaust and airbox are stock, was using the silver key, and wasn't getting on it, shifted to 6th, on freeway with traffic.
Dealer cleared the codes, said it could be any number of things, moisture, bad gas, bad cat, (noticed soot on the left exhaust tip, none on the right) bank 1 is on the right. Suggested just driving it and see if it come back! WTF! So I take it out for a 15 mile drive as the dealer suggested, rush hour and traffic was bad, so I head home and thought I take it out today for a good long drive. Decided to check the oil when I get home.

On 4/3/13 had oil changed plus other fluids in prep for track season. Hadn't checked the oil when it was changed, but now I find oil is overfilled! Sent email to service manager. The owners manual states: Engine damage could occur from overfilling oil. Not sure I should be driving the car until oil level is adjusted. Car had 8671 miles when oil changed only has 8775 now after driving about 40+ miles yesterday, the day the P0420 code was thrown.

My question: Could the oil being overfilled throw this code? Is it safe to drive? I have no way of getting the excess oil out. Looks to be about a quart over. It's above the 2nd hole and almost to the writing on the dip stick above the second hole. I've never had problems with oil changes at the dealer and this is just careless.

Thoughts would be greatly appreciated. Of course it's the weekend so I won't hear from the service manager till Monday.

Could the soot on the tailpipe be from the overfill? Could this cause the P0420 code? Just not sure of what to do. Code wasn't thrown again on the drive after they cleard the code but now I'm not comfortable driving the car to see if the code will reappear.

What's the collective wisdom on this situation?

Cheers!
 
I think you're fine to drive it back to the dealer with the excess oil. If not it's on them anyway plus you still have your warranty. If the code persists take it back to the dealer and make them find the problem. Again you have a warranty so use it.

It's really annoying that our cars continue to throw codes. I know Ford is working on this but it's been a long time. Ford came out with a new flash for the 2013 5.0 motors in December 2012 and the new flash for the 2012 cars was supposed to follow shortly after. Needless to say it hasn't. My BIG concern is the cars are out of production and we'll be left hanging.
 

steveespo

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Overfilled oil can cause excessive oil burning in the combustion chambers which can poison the catalyst making them not work correctly. This is also why engine oils now have minimal amounts of ZDDP which is a great anti wear additive but the zinc in it causes cat failures too. This is why race oils formulated for flat tappet engine should not be used in cars with catalysts and also why most modern engines have roller followers at the camshafts and or rocker arms. Register a record with Ford Service and if the code keeps coming back have them warranty the H-pipe.
Steve
 
Surprisingly when I was initially having overheating issues I was told by at least two Ford engineers to run an extra quart of oil. They said there was no issue with windage or risk of blowing gaskets. I was surprised to hear that and never did add the extra quart but have heard of other guys doing it on their Bosses. So, you should be fine to drive it that way.
 

Boomerstoys

Keep the shiny side up & the rubber side down!
Thanks guys for your responses. Seems the service manager @ my dealer, Bill Pierre Ford, reads his email on the weekends. He arranged to have me take the car to a quick lube place they own. Extracted the oil, hopefully no harm to the motor.

Cloud 9, that is really interesting about intentionally running a quart over. Does anyone know if the oil pan is baffled so under heavy lateral loads the oil pickup is still going to function?

They pulled a full quart from the motor. Lesson learned: CHECK OIL AT THE DEALERSHIP before leaving!

Cheers & thanks!
 
Boomerstoys said:
Cloud 9, that is really interesting about intentionally running a quart over. Does anyone know if the oil pan is baffled so under heavy lateral loads the oil pickup is still going to function?

You would actually be suprised at how little oil is actually in the oil pan at high RPM. :)
 
Boomerstoys said:
Thanks guys for your responses. Seems the service manager @ my dealer, Bill Pierre Ford, reads his email on the weekends. He arranged to have me take the car to a quick lube place they own. Extracted the oil, hopefully no harm to the motor.

Cloud 9, that is really interesting about intentionally running a quart over. Does anyone know if the oil pan is baffled so under heavy lateral loads the oil pickup is still going to function?
They pulled a full quart from the motor. Lesson learned: CHECK OIL AT THE DEALERSHIP before leaving!

Cheers & thanks!
Yes
 

Boomerstoys

Keep the shiny side up & the rubber side down!
Well the bloody code came back. Took her out for an extended drive and about 40 miles into it, the check engine light came on.

Got home and scaned it: P0420
loop open
LOD=25
WT=202
RPM=3024
MPH=37
IGN=42
IAT=67
Ambient Temp = 60
GPH=0.00
TPS=19
This is really starting to P*SS me off. The oil was overfilled by a full quart. I think the O2 sensor is shot or the previously repaired wiring to the sensor failed. I've never had this code which leads me to believe they didn't do the wiring fix correctly or the O2 sensor is know toast.

Any other ideas?

Car goes in tomorrow afternoon and I sent them all the info I pulled off the scan.

Thanks for your help.
 

steveespo

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Check to see that the o2 sensor connectors are fully snapped together. When I did my headers I had the one that connects up on top of the bell housing turn out to be not fully clicked together and it threw a bank 2 cat code. Fixed it and it never came back.
Steve
 

Boomerstoys

Keep the shiny side up & the rubber side down!
Steve, thanks. Car goes into the dealer tomorrow. I'll mention your comment about the connection.

It just bugs the CR*P out of me that this overfill happened and now I have these codes. I think there is oil contamination in the intake that toasted the O2 sensor, (possibly all 4) and may have gummed up the plugs and who know what else. Don't know, I'm not a wrench, but everything points back to the oil overfill in my mind.

The Boss is great, I love it----------------but these gemlins have to go!!!!! (this may just be good old human error and carelessness)

Cheers!
 

zzyzx

Steve
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I think your oil level and your code have nothing to do with one another.

Overfilling by 1 QT is nothing I'd remotely be worried about. I always use 9 QT myself on every oil change. IMO the chance of that causing a cat code is slim to none, with an emphasis on the none.

We have a very long thread here on throwing codes:

https://trackmustangsonline.com/index.php?topic=2598.0

And it has turned out to be a variety of issues: bad cam sensors, bad crank sensors, loose connections, etc.
 

Boomerstoys

Keep the shiny side up & the rubber side down!
ZZYZX: the dealer shares your view that the oil over fill has nothing to do with my P0420 code. They just called and advised that my cat is bad and they are replacing. When asked why this would happen with only 8700 miles on the car, they said it was probably due to the misfires I had on track at Laguna.

I weeded threw the thread you sited and it just appears to be a HUGE variety of alleged reasons and solutions for why codes are being thrown. The most recent post indicates a ECU reflash is going to be done to someone's car.

I don't have a solution and I'm not confident that the new cats will eliminate all code concerns that I've experienced. I haven't had the car on the track since the issue first developed with misfires and I still haven't had the chance to test out the new transmission and clutch to see if it eliminates the lock out issues I've had (Laguna didn't offer an opportunity to hit 5th). The misfires occurred with the Red Key (track key) and the 02 codes with the silver key. It seems to me that Ford needs to review the programing for both keys and step up on clutch and transmission problems that "track" people have exerienced. A fix for both these issues needs to be developed since they are spoiling the reputation of these cars and probably costing the company more money to diagnose and fix these issues on an individual basis.

I've been fortunate to have a dealer that has worked with me. But, what about others that haven't been as lucky?

The clutch & transmission issue presents a REAL DANGER to the owner and others on track at the same time. Does anyone know if Ford Racing or Ford has reviewed the threads on the codes, clutch and transmission threads. Would be great to have someone from the organization comment in general about the issue just so we'd know they are aware and approaching the issue in general. What about the "Boss Track Attack" cars. Are their clutches/transmissions the same or are they upgraded. I know they upgraded the brakes.

This is tragic that a great car like the Boss is being hobbled by these issues that could have been avoided by using more appropriate parts and tuning for this "PERFORMANCE CAR"! Sure hope a universal solution is developed before our warranties run out. I'm now doubting that I'll keep the car after the warranty expires.

This is a great forum!

Cheers!
 
How long did you drive it with the pinched O2 wire??

Not a lot of things can screw up a cat, excess fuel, oil, coolant, and excess heat. Sorry, and a major hit.

Cat efficiency is measured my the PCM by comparing Sensor 1 signal to Sensor 2. A working cat will basically flatline on Sesor 2, meaning voltage will stay roughly the same at a cruise type rpm. Remember the Coyote uses a Wideband for Sensor 1. How were the pinched wires repaired, butt connectors or soldering. I always solder wires if there is any kind of data on that line.

I guess what I'm saying is, the vehicle is a system. If one side of the engine is running like doo doo, the other side will try to even things out. The computer may be smart but it can't think.
 

Boomerstoys

Keep the shiny side up & the rubber side down!
Thousands of miles plus 3 days on track.

The dealer is saying the misfires caused the cat to fail.

As long as this is all warranty, and they solve the code issue, I'm good with it.

Cheers!
 
I have experienced P420 & P430 codes several times on the highway on my way home from the track (after misfire codes). For me, it's the same old story...take it to the dealer...they clear the code and run a drive cycle...no codes...sent home and told everything is fine. At least one good thing is that Cats are mandated by fed law to be waranteed for 8 or 10 years (I can't recall which).
 
Just had the P0420 code come up. I bought gas (premium) @ a different station than normal. I just figured water or too much Ethanol caused the code. After reading this, I'm afraid something else is wrong. The trans has been out for repair and it has since been back to repair an exhaust leak due to said trans repair. Damn, I really don't want to take this thing back to the dealer but I may not have a choice. :(
 
401
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I have a persistent P0430 code that appears every 50-75 kms. I have LTs and no cats and my rear cats are supposedly turned off. I only get the P0430 (B2 Cat Efficiency below threshold) code which never made sense to me since I thought no cats would trigger both codes. I also had a P0155 code at one point which just means all out front O2 sensor failure in B2. However, these are all issues with a car that isnt stock. So I dont think your sensors have failed or at least the front's for that matter. There are pinpoint tests you can do to diagnose the issue. I am hoping to complete this soon.
 

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