458 - CEL OBD2 Code P1303 | FerrariChat

458 CEL OBD2 Code P1303

Discussion in '458 Italia/488/F8' started by ilko, Apr 24, 2021.

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  1. ilko

    ilko Karting

    Aug 20, 2008
    150
    I got the CEL on start-up the other day on my 458. I scanned it with a Bosch OBD2 reader and the code was P1303 - Misfire Cylinder 3. Cleared it, disappeared, but after 2-3 starts it came back up.

    To diagnose the issue, first I swapped coil packs and then spark plugs between cylinders 3 & 4, the code always comes back as P1303. Theoretically, there could be a vacuum leak, or a stuck fuel injector, or even a knock sensor faulty, but those seem unlikely. I'd like to know if P1303 is indeed a misfire in cylinder 3 or perhaps an altogether different fault? I don't have access to a Ferrari scan tool, so I'm relying on my off-the shelf Bosch reader that's why I'm not positive of the meaning of the fault...

    Does anybody have a list of CEL fault codes for the 458 or can somebody confirm what fault code P1303 pertains to?

    Thanks!
     
  2. RayJohns

    RayJohns F1 Veteran
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    What octane and brand of gas are you using? Also, how many miles on the motor?

    Did you pull plug #3 and inspect the plug and electrode yet? Oil in the cylinder can produce a misfire. I'd swap plugs and see if the error moves.

    I personally have had real good luck using this device to diagnose ignition related issues:

    https://www.amazon.com/gp/product/B001TCWMGS/

    Burn time and voltage will tell you a lot. My guess is loose or fouled plug; maybe a cracked housing.

    You could also try reducing the spark gap very slightly and see if it helps. I don't know the spark gap Ferrari runs but I usually run about .025"

    The other thing I do sometimes is cut back the strap over the electrode a bit to aid with ignition.

    Ray
     
  3. ilko

    ilko Karting

    Aug 20, 2008
    150
    I use Chevron 91 octane fuels, the car has 29k miles, last time the spark plugs were changed was in 2017 at 20k miles.

    Yes, as I indicated above, I did pull the plug and swapped it with the one next to it. Both plugs looked the same, gaps were fine, no oil or any other residues were present. Did the same test with the coil packs, made no difference.
     
  4. RayJohns

    RayJohns F1 Veteran
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    I would clean both MAF sensors with MAF cleaner (don't use carb cleaner).

    Also rest the ECU following the battery reconnect procedure in the manual.

    Myself, I'd run a compression check, but probably after resetting the ECU and cleaning the MAF sensors.

    If you have a bore scope /w a light, maybe also check and see if there is any carbon build up on that particular piston.. In very rare cases, you can get a tiny spot of carbon on the position and it can act like a glow plug in rare cases. I had this happen some years ago with a 2-stroke motor. The motor started exhibiting odd issues where it would misfire at higher RPM's and I traced the problem to a glowing carbon deposit on the position.

    Chevron 91 is about as good as it gets fuel wise. Nevertheless, you might consider tossing in a bottle of their Techron injector cleaner (sold at all their gas stations). I've used it on occasion with excellent results.

    Before you clean the MAF sensors on each bank, inspect the leading edge of the sensor and see if it's dirty. You'd be surprised how much havoc a dirty MAF can cause.

    Are you running K&N or BMC style filters? Or the factory air filters? Have they ever been changed?

    Ray
     
  5. RayJohns

    RayJohns F1 Veteran
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    Another thing to keep in mind is that the 458 uses direct fuel injection, as opposed to port fuel injection. This tends to result in more significant carbon deposit build up on the back side of the valves (because direct injection motors don't have any air/fuel mixture flowing over the intake valves). You may also know this, but if not google it and you can see the horror stories.

    I'm not sure how prevalent this issue is on the 458 motor, but it might be worth inspecting the back side of the intake valves just to see if perhaps there is enough carbon build up to be causing a valve to hang open here and there.

    The other thing is get yourself an accurate laser temp gun and check the temps of all the coil packs and/or primary exhaust pipes to see if #3 is running abnormally hot. If you have an OBD2 reader which will show live days, I'd also check both upstream O2 sensor data and see if one bank is running more lean than the other.

    Ray
     
  6. RayJohns

    RayJohns F1 Veteran
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    The other thing you might try is bumping the heat range up one level on just the cylinder #3 spark plug and see if the issue resolves itself for a bit. I wouldn't recommend running a hotter plug long term, but if the error suddenly goes away, it could point to possible oil impingement into that cylinder.

    Just a thought.

    Ray
     
  7. gobble

    gobble Formula 3
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    I had this same problem. I bought a 2,800 mile car that had gone 500 miles in the prior 3 years, so old gas. The dealer told me I needed a new injector rail for $4,800 plus like $4k of labor. I said no chance that was the problem. My launch tool showed the misfire moving between cylinders 3 and 4 when I swapped plugs. I replaced all 8 plugs and have not have a problem for 3 years.
     
  8. ilko

    ilko Karting

    Aug 20, 2008
    150
    Thanks guys! I pulled the connector to the coil pack, the car idled very rough, fuel was igniting in the exhaust system which tells me the fuel injector works fine. As soon as I plugged it back in the idle was fine, meaning the ignition works as well.

    When I clear the CEL and start the car the code comes back but “soft” - it doesn’t trigger a CEL. The second time I start the car the code is registered with a CEL.

    Cleaned MAF sensors but they were not dirty to begin with, air filter is OEM and has 1K mikes on it. I also added a bottle of Techron.

    Drove the car today, it behaves totally normal, no misfires, etc.

    Now what I didn’t mention is that I took the hydraulic lift pump off the car a couple of weeks ago to be serviced, since it was leaking. The first time I drove the car with the pump gone I got a lift error message. The second time I started it up the CEL popped up too. I’m thinking those might be related. I think I’ll wait until the pump is back from repair, will reinstall it and see if that solves the problem.

    I understand that it’s unlikely for an electric pump not related to engine performance to cause a CEL but who the hell knows. That’s why I wanted to make sure P1303 is indeed a code related to cylinder 3 and not something else...
     
  9. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    #9 reisskhan, Apr 26, 2021
    Last edited: Apr 26, 2021
    Yes sometimes better to take matters in your own hands

    Came across a similar situation with a car that came in fully running which was in for some repairs and a full service that included new set of spark plugs....

    Believe it was run low on fuel whilst awaiting around like 8 months for various reasons and parts etc...

    Car was misfiring on one whole bank and Autel/Texa kept showing random misfire on that one bank

    Head scratching as car was running fully fine before it was touched it just didn’t make sense what’s gone wrong

    The old original plugs where thrown away by now plus it didn’t make sense that the new plugs could be faulty as one bank was running fine

    So swapped all the coils and plugs from the working bank to the other side and still the same issue

    So then ripped out the fuel rails and of course Ferrari have stopped selling the injectors Individually and the only option was a complete rail with the injectors which you can guess was not cheap

    There was some available from a breakers yard but still costly and fully knowing that the car was running fine prior just didn’t make sense

    So just found a local Injector repair specialist who tested and cleaned out the all the injectors for circua $100

    The test showed some of them not all 8 weren’t within spec for whatever reason but they cleaned and sorted them for us

    Fitted them back and voila cars running sweet again as before....


     
  10. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    ilko

    Is the car even missfiring or running fine and just shows the light and error code for cylinder 3?

    If running fine you can be onto something with the lift gear removed and some electrics wiring control a lot of other things especially if you saying car was running fine prior to removing the lift gear

    As strange as it sounds but don’t take nothing out of probability

    Came across a Gallardo LP where the intake manifold runner sensor which is a pain to get to had to and had to remove the whole intake mainfold to get to $50 sensor that went faulty and was causing all sorts of havocs with various other sensors and even stopping the car from starting

    Once we got to the sensor disconnected as it was giving the 5v supply and car started up and running

    Replaced it and all was good

    Moral of the story was that one sensor seemed to be attached to other wiring and sensor related stuff which caused havoc lol


     
  11. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    RayJohns

    Take it your a mechanic?

    You really know your stuff and I know what you mean about the carbon deposits and as seen it with my own eyes when the 458 manifold had to come off lol
     
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  12. ilko

    ilko Karting

    Aug 20, 2008
    150
    No misfiring or any issues other than the code. It runs fine.

    Thanks for the replies and suggestions guys, I appreciate it!
     
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  13. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    Ok that’s good it’s running fine

    So codes only come after you’ve removed the lift gear correct?


     
  14. ilko

    ilko Karting

    Aug 20, 2008
    150
    Yes, precisely. Which is why I'm wondering if P1303 is indeed a misfire code or perhaps something else...
     
  15. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    According to google it is

    What is Launch saying?

    Have you got access to Autel or Texa to check or the official machines?
     
  16. ilko

    ilko Karting

    Aug 20, 2008
    150
    The most common meaning of P1303 in Google is random misfire cylinder 3, but there are others. I only have a generic Bosch OBD2 reader.
     
  17. RayJohns

    RayJohns F1 Veteran
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    Nah, I just have a lot of friends who always want their cars fixed for free :)

    Ray
     
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  18. ilko

    ilko Karting

    Aug 20, 2008
    150
    Guys, what do you recommend as a good OBD2 scanner that can hopefully do some coding as well when necessary? Ideally a tool that is cross platform? I work on my Porsches too… Thanks!
     
  19. RayJohns

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    #19 RayJohns, Apr 27, 2021
    Last edited: Apr 27, 2021
    I use this brand:

    https://www.innova.com/

    I have an older 3110 that I used to carry in my Toyota and also a 3160. Nothing fancy but seems to get the job done. They have a pretty nice professional tool also on their website there.

    Ray
     
  20. RayJohns

    RayJohns F1 Veteran
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  21. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    Always the case what are friends are for lol

    The Innova system you are mentioning what is it like?

    Does it go into depth for the Supercars would you say?

     
  22. RayJohns

    RayJohns F1 Veteran
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    It's not as in-depth as the specific ones which are specifically for super cars (which usually cost several thousands of dollars). It's more a generic OBD2 system.

    Ray
     
  23. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    Yes just had a look at the website and I believe the Innova just does reads the Engine Management System for the 458
    And nothing else

    There’s a basic Autel you can get for around £600 and it’s awsome as it can read pretty much all the modules on the 458 alongside Live Data and service reset etc

    Same with the 991 Porsche’s etc

    Have used Texa system as well but not sure how much that costs



     
  24. reisskhan

    reisskhan Karting

    Aug 11, 2017
    74
    Below is the Autel shows you one of the ECU codes as they have 2 ECU’s and a screenshot of a live data snap


    Notice the misfire codes start with P0300/P03xx


    This is when the misfires where occurring as the post above and had to end up have the injectors cleaned up


    Normally on cars when have hard misfire codes they usually begin with P03xx so the code the OP is getting wonder what that really is:


    Off topic RayJohns but if you notice the last code:


    Intake Manifold Flap Stuck


    What does that actually do?


    It doesn’t cause the Engine Light to come on but the code comes back when you delete and rescan the system


    You wouldn’t know it was there if there was no scan taken


    I think one of the rods to the flap is seized which will be attended to in due course but can’t really tell any diffence when driving the vehicle


    Would you have ideas?


    Thanks

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  25. ilko

    ilko Karting

    Aug 20, 2008
    150
    Well, it's fixed. Lsat night I opened up the car to reinstall the front lift pump. When I removed the rear wheel liner I saw a disconnected sensor (pictured). the plug must've slipped while I was taking off the the wheel liner last time. I have no idea what its purpose is other than throwing a CEL, but after I buttoned up the car I started it up and P1303 no longer registers with the OBD2 reader. Went for a test drive, no CEL. I think it's safe to say that the issue has been resolved.
     

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