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Really rich!!

Discussion in 'Engine and Drivetrain/Mechanical' started by 67resto-coupe, Dec 11, 2016.

  1. 67resto-coupe

    67resto-coupe Member

    Holy heck! All of a sudden, my 5.0 roller is running really rich. Don't know if it's an issue with winter fuel or maybe my bowl gaskets have shrunk. I discovered that the bowl bolts were out about 1-1/4 turn each. But look at this pic...would this necessitate jetting down?
     

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  2. 67resto-coupe

    67resto-coupe Member

    Oh, I should add that I'm running a 625 Road Demon, E303, GT40P heads. It's been running well, but I only take it out once every few weeks. But it's always been a little rich, but now it's ridiculous. I currently have the electric choke adjusted to where it's full open. Thanks for any tips.
    -Jeff
     
  3. bartl

    bartl Old Fart

    Have you checked to make sure you didn't blow out the P/V?
     
  4. 67resto-coupe

    67resto-coupe Member

    I'm going to unmount the carb tonite. Good call on the power valve, as you're the second person to ask that question. I bought a rebuild kit, so I'm going to rebuild the whole thing. Considering I bought this carb maybe 10 years ago, I've been told that the gaskets may have shrunk a bit. The car sat from '99-'10 and between '13-'14/early '15 while it was getting painted. I don't recall replacing the bowl gaskets, but since I need to extract the bowl bolt, I'll rebuild it, maybe downjet it and detail the engine compartment while I'm at it.
     
  5. bartl

    bartl Old Fart

    Usually...well, almost 100% of the time, the orifices in the jets don't get LARGER while sitting and crud only makes them smaller. The only things that jump out at me for a rich running engine are P/V or a float needle stuck by debris. If it ran well in the past with that jetting I probably wouldn't mess with them.
     
  6. CUAviator

    CUAviator "I wanna go fast..."

    Reviving old thread -
    I’ve got 302 crate motor, efi, AOD - since I’ve had the car. It has been running super rich (everyone who rides in it smells like gas when they’re done...others can even smell it driving down the road). When I bought it, the original owner said he tunes it rich for racing in central CA. Anyway, I’d like to have the ecu tuned back to something more “breathable” but everywhere I take it tells me I have to remove the ecu and send it to Ford for a reflash, and may even have to do this multiple times until I get it right...at a cost of about $300-600 per.
    A) does this sound right?
    2) can I just take it to a ford dealership???
    d) is there any handheld that I can do it myself?

    Side note, until I do this, is it better to run regular or premium unleaded (both for the engine and for the smell)?

    My wife won’t kiss me until I’ve showered after driving it. HELP!
     
  7. kb3

    kb3 Well-Known Member

    Is it the standard Ford SEFI system? If so, do you know what computer you have? I am not sure how it was tuned to run rich, as it should adjust based on the O2 sensors and the like. There are plenty of shops around the country that can tune it based on knowing your engine specifics, injector size, Mass air meter, etc. I used a company back east called Pro-M Racing. They supplied the tuned computer, injectors, etc. Bolted it all onto my crate 306 and it started and has run flawlessly from day one.
     
  8. CUAviator

    CUAviator "I wanna go fast..."

    And just to clarify - for the tine being, would higher or lower octane reduce the smell?
     
  9. kb3

    kb3 Well-Known Member

    i seriously doubt the octane rating will make any difference. But, I will leave it to some of the experts on this board to answer for certain.
     
  10. B67FSTB

    B67FSTB The NorCal dude from Belgium

    What do you smell ? Gasoline in enginebay or exhaust at the rear ?

    If you don't know anything about what happen to the car/engine in the past , I would check some components like injectors , ecu if they are standart equipt with the car.
    Most men think , bigger is better but thats not always/rarely the case in the automobile technology.
    first you have to know what you have.
    Octane isn't your problem.
    A gasoline leak that evoparize , maybe.
    A engine thats overcaburated/overinjected most likely.
    I think just a software update for your ecu would probably makes a differnence.
    At least you then know you have the correct ecu software for your car.
    Or swap the ecu with another one if thats possible ( vin in ECU ? )
     
    Last edited: Feb 23, 2018
  11. CUAviator

    CUAviator "I wanna go fast..."

    It’s definitely the exhaust. First, when the car starts, you can see it puff out the back. Then when it’s running, when you walk toward the back, it’s asphyxiating. I’ve checked the engine bay, underneath, etc - no smell except exhaust. And I know my trunk isn’t sealed well at all.

    As for octane, ok now that won’t fix the problem. I was just wondering if one or the other would LESSEN the smell until I get this rectified.
     
  12. CUAviator

    CUAviator "I wanna go fast..."

    It's the EECIV SFI-MA12 (A9L). I live in Virginia Beach. What is the best choice to get this retuned - is there a shop that anyone knows of, buy a programmer (then get all up these boards while I try to tune it myself), send it in to "somebody"?

    Again, thanks for all the help.
     
  13. kb3

    kb3 Well-Known Member

    That is the very best Ford computer. Made for manual trans Fox bodies. The A9P was made for auto trans, but either works well for any car. I’m told they take a bit of work to tune yourself, and most local shops around me in California don’t want to touch it. Call around to some of the shops near you.....or call Pro-M. I know, broken record, but they are that good!
     
    CUAviator likes this.
  14. stangg

    stangg Active Member

    According to autozones site, you can still buy remanufactured ECMs ($111 to $207). My OEM A9L was first used on a bone stock 5.0 HO engine, and uses the original tune even though I've since installed the E cam, 30# injectors and larger MAF sensor. The only reason why I went with 30# injectors is because I already had a MAF designed to use them. 24# is probably large enough for my case. Before you go through the expense on replacing the A9L, be absolutely sure that your injectors are matched to the MAF. They work together. You can easily determine the injector size by their color. Also check the coolant temperature sender. If the computer isn't getting the proper coolant temp reading, it might think the engine is cold and run the fuel trim on the rich side. Also check your plugs to see if all are running rich. If only some, then maybe you have a bad plug, bad wire or bad injector. Cleaning/rebuilding injectors is pretty easy if you have a stuck one.

    Also, for manual trans, A9L or A9P will work, but if you had an automatic, if I remember right, the A9P has some logic in it to handle idling in gear . The point being, if automatic, better to stick with A9P.
     
  15. kb3

    kb3 Well-Known Member

    The problem with Autozone is you can’t specify an A9P or L computer. They will just supply any old 5.0 computer. While it will work, it won’t be optimum. I think they require unit exchange which means you lose the A9L you have currently.
     
  16. CUAviator

    CUAviator "I wanna go fast..."

    Correct, I do have an AOD. Just swapped it for a T5. Strangely enough though, it actually drives better now - better acceleration, better shift points (not revving at 2800 rpm in 1st/riding my clutch in 2nd in the neighborhood), smoother idle, and I can actually drive with my a/c on without stalling.

    Just for argument’s sake - said I did just swap the computer (which actually appears to be cheaper than sending it in or buying a programmer), is it just plug and play or does it still need to know what sort of mods I’ve got - CAI, short headers, a/c, 9” rear, type of transmission?
     
  17. CUAviator

    CUAviator "I wanna go fast..."

    And what’s the significance of “losing” the A9L (I really don’t know what the different builds/catch codes/etc mean)
     
  18. kb3

    kb3 Well-Known Member

    The A9 computers are known to be the best of the bunch and used solely on the Mustang 5.0s originally. Other 5.0 powered vehicles had similar computers, but were detuned compared to the Mustang units. You can take one out of a Crown Vic and it will run just fine, just not as great as the A9 units. If you purchase a stock computer you will be just fine with the exception of the "way too big injectors" (at least in my opinion). The SEFI mass air computers are well known for being flexible to engine changes such as cams, intake and exhaust. They learn as they go. But if your Mass Air meter and/or injectors are too far out of normal it may cause and issue. Without scrolling up, I think you said you are running 40# injectors. Do you know what size mass air meter you are running? You may get away with just changing back to a 19# injector and be ok.
     
  19. RapidRabbit

    RapidRabbit Well-Known Member

    I had a hard time locating a stock computer for my efi swap.

    The older 5.0 computers are usually programmed or tuned via a plug in chip. I don't believe they can be done any other way, but I may be wrong. They don't have the obdII.



    Sent from my moto x4 using Tapatalk
     
  20. stangg

    stangg Active Member

    Just reiterating things you NEED to do before even looking at the computer... all's it does it take input from sensors and tells the engine's systems what to do. Garbage In -> Garbage out.

    Before you go through the expense on replacing the A9L, be absolutely sure that your injectors are matched to the MAF. They work together. You can easily determine the injector size by their color. Also check the coolant temperature sender. If the computer isn't getting the proper coolant temp reading, it might think the engine is cold and run the fuel trim on the rich side. Also check your plugs to see if all are running rich. If only some, then maybe you have a bad plug, bad wire or bad injector. Cleaning/rebuilding injectors is pretty easy if you have a stuck one.

    Also, for manual trans, A9L or A9P will work, but if you had an automatic, if I remember right, the A9P has some logic in it to handle idling in gear . The point being, if automatic, better to stick with A9P.
     

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