Advice Needed For Bosch Fuel Injection On 80 308 | FerrariChat

Advice Needed For Bosch Fuel Injection On 80 308

Discussion in 'Technical Q&A' started by Shamile, Nov 30, 2003.

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  1. Shamile

    Shamile F1 Veteran

    Dec 31, 2002
    6,712
    Lakeland FL
    Full Name:
    Shamile
    Dear Ferraristi,

    I have a question on a Fuel injection matter. I have an 80 308 that I think is having a rich conditon. I get about 5 miles per gallon and I have to put a large bottle on Cheveron Techtron in every tank. If I don't, I get hesitation, missing, spitting, poping, back firing. As soon as I put the Techtron, smooooth as silk. I don't believe it is spark related, because as soon as the techtron is added to a fresh tank of fuel...perfect.

    Is there a proceedure for diognosing ( sorry no spell check ) this. I don't think I can do this myself but would like to point to some likely candidates for the shop.

    If is a question of some simple parts replacements, all your input would be greatly appreciated.
     
  2. ricrain

    ricrain Karting

    Nov 1, 2003
    213
    Dallas Area
    Full Name:
    Ric
    Holy Richness, Batman! That's really piss-poor mileage, even for a 308. 14-18 MPG is "normal". First thing is to check the CO2. If you have cats, you have to check the CO2 upstream. If not, you can check it in the tail pipes. I think (from memory) the correct CO2 is 1.2%.
     
  3. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    7,017
    Groton, MA
    Full Name:
    Verell Boaen
    How about adding your location to your profile so we can figure out which shops might be in your area.

    Odds are your mixture is way rich. To the point that I'll bet your exhaust really stinks also. If you pull a couple of spark plugs most likely they'll have a dark chocolate brown glaze on them. All symptoms of being too rich.
     
  4. Shamile

    Shamile F1 Veteran

    Dec 31, 2002
    6,712
    Lakeland FL
    Full Name:
    Shamile
    Dear Ferraristi,

    First, since Rob changed stuff around, I can't find access to the personal profile. I'm located in Sunny, warm breezes through the palm trees Florida in Lakeland. ( Between Tampa and Orlando ) I usually deal with the Ferrari dealer in Orlando, Central Florida Ferrari.

    I do like working on the car so that's why I ask for all your help instead of just handing off the cash....I mean the car. :)

    I don't have any cats, just straight pipes to a Stebro Stainless exhaust.( Lovvvvve the sound) This car does not come with a O2 sensor.

    How do you check the CO2? We don't have emissions tests in our county.

    Yes, the exhaust does smell rather bad and I do have light soot on the back lenses if I wipe them with a clean cloth.

    Again, your help is greatly appreciated.
     
  5. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    7,017
    Groton, MA
    Full Name:
    Verell Boaen
    Don't know your area, so can't help w/a recommendation. However I'm sure another chat member will be able to.

    Mixture adj also came up in this thread which has a good photo of the mixture screw location. The adj is extremely sensitive, and can really only be done correctly with an exhaust gas analyzer.

    http://ferrarichat.com/forum/showthread.php?t=2483

    If you don't come up with a shop, your best bet is a Mercedes dealer. Mercedes used the BOSCH K-Jetronic CIS system during the same time as Ferrari & still should have someone trained on it. BTW, according to the BOSCH web site, the exact BOSCH p/n fuel accumulator was used on an '89 Mercedes model, a 250 or 230 SL as I recall.
     
  6. Shamile

    Shamile F1 Veteran

    Dec 31, 2002
    6,712
    Lakeland FL
    Full Name:
    Shamile
    Dear Ferraristi,


    Verrell, Why do you mention a fuel accumulator? Is that related to my problem?

    I did find that thread, great picture of the adjustment screw. I just don't have the analizer to do the adj. I will probably try a 1/4 turn to lean to see if it improves. Do you think any adj. is unwise with out the analizer?

    Arrgh...I wish there was a spell check.
     
  7. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,989
    USA
    Take it to a shop, you are doing this blind without a proper machine to check the exhaust. You are wasting your time, and risking damaging your car.
     
  8. 4Webers

    4Webers Formula Junior

    Nov 12, 2003
    276
    Texas
    Full Name:
    Darrell
    Porsche 911's from '74 through '83 used the Bosch K-Jetronic CIS too, so that would be another possible source of expertise. I wonder who charges more, a Porsche shop or a M-B shop...
     
  9. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    7,017
    Groton, MA
    Full Name:
    Verell Boaen
    Awwww, darn it,short in headset. I don't need a spell checkeer, I need a DWIM (Do What I Mean) editor.

    I meant to say that that the exact same fuel distributor was used on an Mercedes.

    You definitely need some kind of an exhaust gas analyzer.

    I'm running a bit rich also.

    A BARE MINIMUM GAS ANALYZER:
    I'm planning on installing a pair of std O2 sensors in my collectors, then use an LED Fuel-Air ration meters to tweak mine in.

    This is nowhere near as precise as using a true wide-band A/F sensor, or even better an exhaust gas analyzer, but I can make sure I'm somewhat richer than stochimetric rathar than way too rich, or lean.
    I've had good luck with this setup setting up my Rx7 TurboII after performance mods.

    CAUTION: This probably isn't precise enough for a cat equipped car that must pass an emissions test, altho it should be able to come close.
    BTW, if the car already has an O2 sensor, you just need to connect the meter to it with a shielded cable. Shielding is vy important as the signal is high impedence & fairly low voltage.

    I've heard that one of the VW models uses an O2 sensor with a much wider band response than a std O2 sensor, but aren't much more expensive. I'm going to look into it also.
     
  10. Shamile

    Shamile F1 Veteran

    Dec 31, 2002
    6,712
    Lakeland FL
    Full Name:
    Shamile
    Dear Ferraristi,

    Verrell, I mean't I need the speck checker. I can see I'm spelling things wrong, but I don't want to run to the dictionary when on-line :)

    I will take all your advice...I won't adjust it, I will take it to the shop.

    When I was dealing with Porsches, I used Dave White Autosports in Tampa. They race prep a lot of stuff for Sebring & Daytona.

    I do use the Ferrari Dealer in Orlando, but I find they are overboard. Why is it 3 hrs for a front wheel bearing change and $ 350.00 for an alignment. Even the Porsche dealer doesn't charge that much.
    ( standard stuff that can be related to any high-end sports car )
     
  11. Verell

    Verell F1 Veteran
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    May 5, 2001
    7,017
    Groton, MA
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    Verell Boaen
    Hmm,
    I think it took me more like 6 hrs the 1st time I changed my front wheel bearings, and then about 1.5hrs to redo one wheel when I discovered I'd left the seal off. I'd say 2+ hrs for someone more experienced if the fittings haven't corroded too much. Also, I'm sure they're using a 'flat rate' book.

    I took my car to a local Mercedes restoration & service shop for it's 4-wheel alignment. $300 & it took the guy 6 hours or so. I think he earned his I stayed & watched from the waiting room. FoNE sends all of their suspension work to this shop, & they have a vy good reputation.

    350 for only a FE alignment seems pretty high.
     
  12. Shamile

    Shamile F1 Veteran

    Dec 31, 2002
    6,712
    Lakeland FL
    Full Name:
    Shamile
    Dear Ferraristi,

    Verrell,

    Thanks for the pricing feedback. I don't feel so ripped-off now...well at least I'm not alone. :)
     
  13. atlantaman

    atlantaman Formula 3

    Mar 31, 2002
    1,726
    Roswell, Georgia
    Full Name:
    Charles
    To get 5 mpg you have a SERIOUS problem--do not drive the car!!

    Often you will find that a clogged or leaking vacuum line forces that kind of milage so check them out carefully--

    I was running my car too rich for last month and eventually it caused the piston rings to fail( gas was washing oil from cyl walls)--complete rebuild resulted--or actually in my case--new motor. AND I was actually getting 16 MPG during that time.
     
  14. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    7,017
    Groton, MA
    Full Name:
    Verell Boaen
    Ask Dave White if he'll service your 308. 911s also used the K-Jetronic system, so he'll be familiar with setting the mixture on a K-Jet system.
     

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