Exhaust manifold issue cause of intake manifold.. must read | FerrariChat
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Exhaust manifold issue cause of intake manifold.. must read

Discussion in '360/430' started by Mr Aryan, Apr 30, 2013.

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  1. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
    Full Name:
    Mr Aryan
    #1 Mr Aryan, Apr 30, 2013
    Last edited by a moderator: Sep 7, 2017
    I don't wish to see anyone of you go through what i've been through... and really glad it didn't get worse and burn my F430..

    - like all other normal days got out in my F430, drove like 20-30 mins and went to gym, after few hours left gym going to some car show we had, driven it like 30-40 mins, floored it few times just like how every F owner does..
    - at the show after few hours i started to have a headache, so got back into my car to go home, started the car and didn't really pay attention to the sound.. after i moved, started to notice my car got loud... I actually thought it's because of the headache i had, everything is getting loud.
    I just went home, parked my car...
    - next day, started the car and left home... i was not happy of the sound and now really felt it's getting louder, when one of my friends was in his car behind my car and he called me, he was like why your Ferrari doesn't sound like a Ferrari!! here i was sure that the exhaust manifold got cracked like most F430 owners... went back home and went at the back of the car, heard the right side exhaust tip sounds different, so i knew it's the right side exhaust manifold...
    - I called up the garage i deal with and took appointment with him. he's been expert in other European cars, and my Ferrari was the first he worked on a while back and changed all the bushing, bull joints, springs, suspension work basically. and i really trust him.
    - took the car to him at the end of his duty so the car cools down, and next day morning he could check for any leakage, when he called me next day and said yes i had put my hand close the right side manifold cover, and can feel there is gas coming out.
    - I just placed an order with Ricambiamerica.com, and big thanks to Daniel as usual 3 days later and my new OEM exhaust manifolds were here, and handed them to the garage.

    here where problems started.
    - garage called me up stating that they installed the new manifolds, and the right side one glowed in less than 2 mins after they started the car, and they shut off! the mechanic said that the pre-cat must be blocked! I told him it's impossible! he suggested why don't we just weld the old right side exhaust manifold crack and put it back and see if it glows like the new one?
    I agreed.. but also informed Daniel about my issue who might have been aware of any similar issue before, but as soon as i told him and showed him the pics, he told me something in the car must have been wrong and better to take it to the dealer! But i really don't want to deal with them as last time i had a big issue with the dealer were they threw my car in their open backyard for a whole 3 days without working on it.. and had to complain to Ferrari Italy.
    anyway, I couldn't guess anything as the car was running normal with no issues before going to garage.. and now no CEL on the dash is showing.. no indicators! and keeps burning pre-cat!
    something gets that hot seemed to me it's getting lean… but that would usually caused by a bad O2 sensors which comes into the manifold! but since there was no CEL, i knew it wasn't from the sensors.
    - anyway, they removed the new right header and I looked inside, seen the pre-cat got into pieces!!! :(
    - so i just opened the old right side headers cover, and found out that the header was cracked, and a big piece had been fallen from it (which caused the loudness)... it was an easy welding, done and took it back to the garage to put it back on the car
    - next day, garage installed the old right side manifold only after welding, and called me up and said that now the new left side manifold glowing in just less than 2 mins!! when i asked how about the right side old headers now? he said it looks ok!
    I started to think that the new manifolds pre-cats material might be bad which causing that! but still wasn't sure…
    - I told the garage now remove the left new manifold, and let's put the old one also… but before that let's remove the cover of the old manifold as well to check if there is any crack as the cover from outside seemed it got some heat on the corners.
    and as i guessed, the old left manifold was also cracked… so I also welded it to put all the old stuff back to make sure what's going on!!
    the new left manifold pre-cat didn't get into pieces like the right side as they shut of the car quickly before it burns it.
    - this time i was there and i sat in the car and they raised the lift and asked me to start, in just less than a min they said shut off, the old right manifold is glowing now! one of their expert workers came to me and said once they had a same issue on a Mini Cooper S where the intake manifold was leaking air, and kept glowing the exhaust manifold! I told him i don't think the manifold would just leak in a day and night just like that!! i was referring to the intake manifold gasket as this is the only think i would think of gets an extra air in!!!

    - now i was sure the new manifolds were totally fine after i've seen the old manifolds are glowing… something is wrong with the car.. something happened while the car was in the garage.
    - the garage knows the mechanic who works with Ferrari, so he called him and the Ferrari mechanic said it's bad fuel! but i told them it's impossible as i drove the car for more than 100 miles with current full tank and no issues! why now it keeps burning the pre-cats! anyway, told the garage ok, let's assume it's bad fuel, they drained the fuel, and put new fuel… it was the same, manifolds keep glowing!
    - at the same time one of my friends F430 arrived to change his clutch, when i asked the garage to try the his O2 sensors on my car… and that would be my last option to try! and they did change them… and was still glowing! :(

    - I gave up at the end, by the time i decided to take it the dealer with no other choose, that expert worker came to me, and pointed on the plug that comes into the intake manifold and said that the other Ferrari has a piece here, and you don't have it!!!
    I really never thought of this plug! never looked at it!! never thought that this piece would ever come off!
    I tried to look around if i could find the plug.. couldn't find it.. the guy told me if I would allow him to block the hole with some robber just to make sure if the manifold would still glow.. and he kept saying that he's 100% sure this would solve my issue as the Mini Cooper S! and he blocked the intake hole… the car started like nothing happened!!

    Now…
    - you may ask if i have noticed any idle issue, the car started normally, and idled like when you turn the main switch back on, the ECU is like on learning process which usually idles normal in just 1-2 mins, but the glowing manifold was faster than waiting for the car to get normal idle..
    - no CEL indication came for having intake leakage..
    - cracked manifold was probably there at the time i bought the car, as the car had very bad engine mounts and tranny mount.. but now because the right side manifold broke a piece of it where made a big sound change which made me notice..

    - So what made this plug to come off like that?! I would guess it backfired maybe the time the garage wanted to start the car?! i don't think it would be that easy for an important piece to come off just like that!
    - the plug should hold into a bearing inside the hold in the intake manifold… anyone knows what is this piece for? what does it do!!

    i'm just thanking god 1000 times that this happened at the workshop garage while they were looking at the manifold, cause if that had happened at home while i just warm up the car, i usually keep the car 15mins to warm up, and that would probably burn the car plus i have some flammable stuff in the garage which would put a whole house into fire!! :(
    I started to get worried and makes me keep an eye on it every time i need to ride the car… :(

    so at the end, I again tried to look for the plug.. after 30mins of searching, found it hidden somewhere under the intake… it doesn't look bad or broken..
    and I had ordered another new set of exhaust manifolds… installing them after the weekend…


    any input would be appreciated…
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  2. thoang

    thoang Formula 3
    Owner

    Apr 12, 2004
    1,990
    SF Bay Area
    Full Name:
    Tuan Hoang
    #2 thoang, Apr 30, 2013
    Thanks for the long explanation. Glad you were able to avert a major catastrophe. How did you secure the "plug" back onto the intake manifold?
     
  3. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
    Full Name:
    Mr Aryan
    #3 Mr Aryan, Apr 30, 2013
    still didn't..I even got a new plug before i found the old one.. but it should just get plugged in.
    want to have some feedbacks first and if there is a way to secure it from coming off again..
     
  4. Mo T

    Mo T Formula Junior

    Nov 26, 2011
    478
    Saudi Arabia
    Full Name:
    Mohammed
    #4 Mo T, May 1, 2013
    Sorry to hear about your issues bro, I am glad you caught it just in time before taking it to the dealer, I don't know what is this hole and part for but no one would have figured it out.

    If you ever need anything from Ferrari Bahrain, hit me up as I know the owner and might be able to help.

    Let us know how it goes from here onwards.
     
  5. RWebber

    RWebber Formula Junior

    Apr 17, 2013
    304
    Grasslands, USA
    Full Name:
    R Webber
    #5 RWebber, May 1, 2013
    What does the intake plug do and why is it there?
    Seems like a catastrophe
     
  6. Trent

    Trent Formula 3

    Dec 10, 2003
    2,013
    Indialantic, FL
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    Trent
    #6 Trent, May 1, 2013
    Last edited by a moderator: Sep 7, 2017
    Wow what a story; Thanks for the long and detailed story and explanation. I know writing in a foreign language is extra effort.

    Here is my educated guess on the physics (or chemistry in this case):
    ==========================
    I suspect that the extra Oxygen shifted your Stoichiometry (aka AFR [Air to Fuel Ratio]). Optimal for HP is 13:1, but the EPA mandates 14.7:1 to allow for optimal Catalytic converter operation. So 14:1 is 14 parts oxygen and 1 part hydrocarbon (aka gas, fuel, C8H18). Any more Oxygen and the mixture considered lean, and less and its considered rich.

    Max power at 12.6:1 AFR
    Max Economy at 15.4:1 AFR

    Fuel will fail to burn at all above or below specific AFRs:
    Below: 6:1
    Above: 25:1

    So my theory goes like this. The air leak is at the rear of the engine near Cyl 4 and 5 caused their Stoich to exceed 25:1 and thus combustion failed to occur. Thus unburnt fuel was being catalyzed in the pre-cats causing the pre CATs to exceed their operating temperature range vastly reducing their MTBF (mean time between failure). Its considered a leak because the Mass Air Flow meter can not meter it.

    Note: If you were driving the leak would probably not had much effect on your AFR. Why? Because with the main 2x throttle bodies open the metered air Vs leaked air ratio will decrease to near zero. For example the throttle bodies are 80mm. The plug hole is ~20mm.

    Total area:
    Throttle Bodies 80mm x 2 : 5026 x2 = 10,052 sqmm.
    Leak through missing 20mm cap x1: 314 sqmm.

    So at a throttle body open at 3.1%, there is a surface area of 314, thus the AFR will be lean by a factor of 2. Or likely 28:1.

    At Idle the air flow is very low (unknown to me), but at 1% the AFR could be as lean as 56:1

    At Idle the throttle bodies are almost completely closed, thus any leak is amplified verses throttle body open situations.

    So with Cyl 4 and 5 having AFRs of >=25:1 the spark plug will not ignite the fuel due to it being too lean to support combustion. This fuel will however get catalyzed by the pre CATs. The pre CATs as with most cats are designed to Catalyze (burn) a maximum amount of fuel. If they catalyze too much fuel it will increase their operating temperatures beyond specification possibly causing damage or failure of the CAT, headers, etc. Even CATs will burn and/or melt at some temperature.

    I would have guessed that the car would run a little rough if Cyl 4 and 5 are non functional. But I tested this previously by removing the COPs (Coil Over Packs) and thus spark, while running my 430 on 6x cyl. It started and ran just fine, at least at idle. 4 strokes need at least 4x Cyl to run somewhat smooth. I did not drive it, but then again you car would reach a normal AFR as soon as you added throttle input.

    Summary: At idle the pre CATs exceeded their operational temperatures because they were catalizing unburnt fuel, likely from Cyls 4 and 5 due to the extra 314 sqmm of air intake not metered by the Mass Air Flow sensor increasing the AFR beyond combustion stoich of 25:1.

    Attached Ricambi image of intake runners. Note the proximity of the leak to the rear most Cyl 4 and 5.
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  7. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
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    Mr Aryan
    #7 Mr Aryan, May 1, 2013
    Thanks Mo..If you mean Zayed Al-Zayani, my brother also knows him.. I just don't like to be treated good only because I know someone!

    check your pm.. ;)



    thanks Trent.... that exactly explains what happened with me...

    but now what does this plug do? how can we avoid it coming off?
     
  8. Trent

    Trent Formula 3

    Dec 10, 2003
    2,013
    Indialantic, FL
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    Trent
    #8 Trent, May 1, 2013
    The plug could be from:
    1. Manufacturing apparatus
    2. Tuning or other QA step
    3. Shared platform relic (engine shred with and derived from Maserati development for quattroporte and Gran Turismo)

    One thing is or sure, it probably serves no functional purpose.

    How to secure it? Epoxy, RTV, other high temp glue.
     
  9. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
    Full Name:
    Mr Aryan
    #9 Mr Aryan, May 2, 2013
    Last edited by a moderator: Sep 7, 2017
    I thought of high temp glue, but when i saw a bearing inside.. it will stick the bearing as well and won't move.. thought of gluing on the orange mark.
    that's why i need to know if it's important to keep the bearing free...
    then maybe just have it glued on the green mark?
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  10. awatkins

    awatkins Formula Junior

    Apr 10, 2005
    396
    SFO Peninsula
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    Alan Watkins
    #10 awatkins, May 2, 2013
    Last edited: May 2, 2013
    Looking at the parts diagram and 430 workshop manual it appears this plug is closing one end of the bearing arrangement for supporting the "rolling drum" (215068 or 220668 depending on year) which is there to "compensate the two intake manifold capacities". From your photograph it also appears it may serve a locating function for the bearing which may be attached to the drum. You could probably determine this by rotating the drum from its opposite end and observing the bearing. Unfortunately the manual does not address removal and replacement of the plug probably because the rolling drum is removed from the opposite end (WSM sec. B7.02) and thus they do not expect removal of the plug as part of normal service. From the appearance of the photographs there is no mechanical means to retain the plug other than friction so my guess is some silicone RTV to glue it in place along your orange line would be suitable. Perhaps the factory uses Loctite there but in your case forgot or else it failed. If that doesn't seem secure enough I supposed you could put it in place and then drill into it radially and install a pin, or if drilling is out of the question an "L" shaped sheet metal retainer attached to the two screws above would make sure it never leaves.

    It would be interesting for other 430 owners to look at theirs and try to determine what keeps it in place. I would do this but my 360 is not blessed with such a device.
     
  11. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
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    Mr Aryan
    #11 Mr Aryan, May 2, 2013
    thanks Alan.. very helpful info from you and Trent...
     
  12. Temuri

    Temuri Karting

    Apr 12, 2011
    119
    Moscow
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    Temuri
    #12 Temuri, May 12, 2013
    As I noticed manifold problems are usual problem happening with almost all f430. Is this because of the quality of the metal or something else?

    Are there any suggestions?
     
  13. Mr Aryan

    Mr Aryan Karting

    Sep 23, 2008
    182
    Bahrain
    Full Name:
    Mr Aryan
    #13 Mr Aryan, May 12, 2013
    engine movement and vibration while exhaust holding tight in place cause the issue with exhaust manifold.
    solution as most say is to go with Capristo exhaust brackets.
     
  14. Temuri

    Temuri Karting

    Apr 12, 2011
    119
    Moscow
    Full Name:
    Temuri
    #14 Temuri, May 13, 2013
    That's what I did. Car runs noticeably better.
    Thanks for reply.
     

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