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308 hard starting

Discussion in 'Technical Q&A' started by Cooly0, Sep 26, 2004.

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  1. Cooly0

    Cooly0 Karting

    Nov 2, 2003
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    Jozy
    #1 Cooly0, Sep 26, 2004
    so my fuel pump went a few weeks ago. While attempting to track it down, a fuel line splitter was damaged (1980 GTSi used 2 filters) and the part was hard to track down. Well I ended up fabricating a line to fit the one filter like the rest of the 308's. Well is seems, at least to me, that it is now very hard to start. The Air/Fuel ratio has to be adjusted richer in order for it to actually start, but is very tricky to start, often require me to play with the gas pedel just to start it. It turns over well. I can press down the air/fuel adjustment to let gas in and can pretty much start it up right away. So it seems to be a pressure problem. the line that I made to fit only has one bend in it but seems to have good clearence for the fuel.

    I have heard something relating to this, that the accumlator may be the next suspect. Anyone else have any Idea's.
     
    Horseman55 likes this.
  2. 308GTS

    308GTS Formula 3

    Dec 27, 2001
    2,223
    TN
    #2 308GTS, Sep 26, 2004
    Check you cold start injector and thermo time switch first. Verify that your CSI works when first cranking. If it isn't spraying it will cause your car to start hard and stumble when first lit.
     
  3. M.James

    M.James F1 Rookie

    Jun 6, 2003
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    #3 M.James, Sep 26, 2004
    I went looking through my 308 Parts Manual - where is the Thermo Time Switch located on the engine, and is the CSI the same component as the P/N 121743 Warm Up Regulator???
     
  4. Cooly0

    Cooly0 Karting

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    #4 Cooly0, Sep 26, 2004
    I actually cant seem to find it. The manual doesnt exactly point to where it is.
     
  5. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
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    Mitchell Le
    #5 yelcab, Sep 26, 2004
    You will probably need a CIS Fuel Pressure Tester. And, you will need to test

    System pressure (likely part of your problem)
    Cold control pressure
    Warm control pressure
    Hot control pressure
    Residual pressure.

    This information will tell you a lot about whether it is your

    Fuel pump, check valve, filters ...
    WUR (cold and warm start problems)
    Accumulator (hot start problem)
    Thermal time switch (starting problems in general)
    Start up injector etc. (starting problems in general)

    Lacking all of this information, it is a wild-ass guess. Since you messed with your fuel pump / filters most recently right before the symptoms, I would venture a guess that your system pressure is low.
     
  6. Cooly0

    Cooly0 Karting

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    #6 Cooly0, Sep 26, 2004
    Well I think I may have found it, on what I think is the injector there are the lines to the switch I assume. These lines do not get any type of voltage running through them at any time. I'll take a pic and show, and suggestions on how to resolve this?
     
  7. Cooly0

    Cooly0 Karting

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    #7 Cooly0, Sep 27, 2004
    Ok so this is what I found. There is no voltage coming off of the the line going up to it. Any Ideas how to trouble shoot this ?

    Thanks anyone
     
  8. carlrose

    carlrose Formula Junior

    Nov 25, 2003
    327
    #8 carlrose, Sep 27, 2004
    Hi Mr. Kuehl,

    The cold-start injector (CSI) only fires on command from the thermo-time switch, and only for a brief interval at that. Engine must be cold (morning start). Put a test light "bridge" across the terminals and crank over; this will light for 1-2 sec then extinguish. If not, you could potentially have a wiring or thermo-time switch (TTS) problem. Another trick is to remove from manifold, remove the coil wires, put the CSI in a small jar, and crank over. If functioning you will get a brief gasoline spray.

    Hope this helps a little bit.

    :) Carl
     
  9. Cooly0

    Cooly0 Karting

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    Jozy
    #9 Cooly0, Sep 28, 2004
    Well, the problem I am having really is checking this thermo switch. I cant seem to find it. I've taken a voltmeter to the line and have not gotten one blip. This thermo switch may be the problem. I was able to assure the injector is not clogged. It does spray when power is applied to it.
     
  10. Ferrari_tech

    Ferrari_tech Formula 3

    Jul 28, 2003
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    #10 Ferrari_tech, Sep 28, 2004
    As far as I can recall the thermo-time switch is located in the "V" of the engine.

    Here's some data that shows how to check the values of the time switch, there are different types - the type number is stamped on the side of the switch.
     
  11. Cooly0

    Cooly0 Karting

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    Jozy
    #11 Cooly0, Sep 28, 2004
    Ok the black circle is where the oil filter would be. The Red is the connector I found, also no voltage from the line with the car on or off. Where can I go from here?

    Thanks
     
  12. M.James

    M.James F1 Rookie

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    #12 M.James, Sep 28, 2004
    Thanks for posting Pics....this helps me see whats-what in my own engine!
     
  13. Cooly0

    Cooly0 Karting

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    #13 Cooly0, Sep 28, 2004
    what are you having problems with, I could probably help. This is one of the few things that are bewildering me.
     
  14. M.James

    M.James F1 Rookie

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    #14 M.James, Sep 28, 2004
    BTW, the first device, circled in red, is identified in my Parts Manual as the Auxiliary Starting Assembly (the device connected into the right side of the Manifold cover) - Part number 115474.

    It has an electrical connection at the bottom, and a hose connection in the side - fuel line???
     
  15. M.James

    M.James F1 Rookie

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    #15 M.James, Sep 28, 2004
    Well, my engine starts up just fine, the idle is rough/horrible until the engine warms up. I have to manually give the car more throttle with the accelerator pedal while the engine warms up - the fuel injection/cold-start/warmup mechanisms will not auto-adjust the engine's idle to 2,000 RPM where it should be while the engine is trying to warm up.

    Once warm, the engine settles to just below 1,000 RPM idle - fine, but alittle low. Running the A/C while stopped will stall the engine out. I understand there's an idle adjustment screw on the engine somewhere, I may tinker with this once the car is warmed up so the engine settles around 1,100 RPM or just a touch more. However, this doesn't solve what the engine is doing when it is stone-cold.

    I looked at the Aux Air Valve, as recommended by some posters here. That part appears to be working fine once cleaned/lubed and rewired. The problem gradually got worse over the past three/four months, so something recently went 'bad' since I had the car. The cold idle mechanism worked great this spring, so I think we're looking at the same culprits here.
     
  16. Cooly0

    Cooly0 Karting

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    #16 Cooly0, Sep 28, 2004
    well the idle adjustment is a knob right by the black boot. It is a large allenwrench, I think 12-14MM but you can use your hand, It's easier. And when you say at cold with the warm up? It just sit's at idle 1,000 ?

    Addition 2: And If you look in the lower left coner of the pic, you will see the spring of the idle adjustment. Now the position will vary depending on what model you have (i.e. GTx , GTxi , GTx QV)

    Addition: The pic below: the Dark blue is the electric (cold injector) that I am not getting any voltage to, and that is the only problem with that.

    The light blue is where the fuel enters from the Black fuel line
     
  17. M.James

    M.James F1 Rookie

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    #17 M.James, Sep 28, 2004
    Regardless of engine temp, my engine wants to Idle at just under 1,000 RPM. This is too low when its cold, but is just fine when the engine is fully warmed up. However, at this low RMP, the engine has trouble driving the Auxiliary drive belt, and hence stalls when the A/C is running at idle.
     
  18. M.James

    M.James F1 Rookie

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    #18 M.James, Sep 28, 2004
    BTW, right below the "cold start injector" of my QV is a device called the Warm-Up Regulator. Anyone ever troubleshoot this device?
     
  19. Cooly0

    Cooly0 Karting

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    #19 Cooly0, Sep 29, 2004
    Well, on mine, that device right below the cold injector (in the picture) with the green wire going into it is actually the fuel system pressure regulator. Something you might want to check. On the radiator there is a thermo switch with to spade connectors on it. Make sure they are both attached and have a good connection. these being disconnected, I believe will cause similiar problems. All though, Connecting the too together will sort of bypass the warmup all together. But then I believe your Water temp will always be the same aswell.
     
  20. Ferrari_tech

    Ferrari_tech Formula 3

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    #20 Ferrari_tech, Sep 29, 2004
    Jeff,

    Can't lay my hands on a 308 wiring diagram, but have one for an early 308QV, it should help.

    The answer to your question is that the thermo-time switch gets it's power from the start valve relay (#90 in diagram)

    Some of the colour codes on the wiring probably won't match yours, however it should make it easier for you to trace through the circuits.
     
  21. 328KNB

    328KNB Karting

    Jun 14, 2004
    59
    #21 328KNB, Sep 29, 2004
    Had the same problem with my 81 GTSi. Agents view was that the ECU had gone faulty. DIY fix - which the agent left in place - and which worked fine for the 4 years I had the car - was to disconnect the plug to the CSI. This leans out the start mixture and she always started on the button, even in winter.

    Good luck
     
  22. Ferrari_tech

    Ferrari_tech Formula 3

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    #22 Ferrari_tech, Sep 30, 2004
    Jeff,

    You have mail
     

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