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  #1  
Old 07-03-2005, 01:53 PM
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Join Date: Jul 2005
Location: lakeland,florida
Posts: 24
sometimes she does...sometimes she dont

my 87 420 sel has a problem that i would like to fix, on a "cold" start in the morning (i live in central florida, it averages 70-80 deg. in the morning) it almost always starts right up and idles smooth. but if i drive it to full operating temp. and try to restart, it cranks as though it has lost fuel pressure, i want to put in a couple check valves in the fuel pumps and an accumulator, but thought maybe i should ask the experts here. i feel that it probably couldnt be injector related as it starts and holds pressure sometimes as long as a week between "cold" starts. i have tried to cycle the fuel pump many times by turning the key on/off and letting the pressure build before a warm start and this doesnt seem to work. when it does this cranking over many times routine it seems as though it is flooded and smokes black and smells like gas when it starts(making me think injector problem) but the only catch to it is, if you pump the gas, it will start sooner(ie:starving condition), if you hold the throttle open(ie:flooded condition)it wont?!!?! the plugs look fine, a little rich maybe but i live in the city so they are about as they should be. i dont have the pressure gauge to check the system and really dont want to start throwing parts at it, any suggestions? also once the car is running, it is smooth and has no issues, only the warm start issue. does it seem reasonable to change the check valves and the accumulator and go from there?
p.s. had recent tune up and fuel filter

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2003 audi A6
2002 porsche boxter
1989 jeep grand wagoneer
1987 m/b 420 sel
1966 vw type 1
1965 mustang "a" code gt
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  #2  
Old 07-03-2005, 02:46 PM
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Join Date: Jul 2001
Location: SoCal
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Pumping or holding throttle open don't have the same effect with FI because there is no accelerator pump as in a carb. All indications seem to be an over-rich mixture. 'Pumping' may get it started because you are alternating rich/lean conditions somehow, and it fires on the lean mode.

Check valves are built into the system, including in each injector. If one injector were leaking, you should start ok, with initial misfiring until the port clears of fuel.

Steve
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  #3  
Old 07-03-2005, 08:20 PM
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Join Date: Jul 2005
Location: lakeland,florida
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i have seem similar threds about this subject, but none of the threads i have seen have the same condition i have, most of them are accompanied by a rough idle or roughness when the car is cold or warm etc. i have none of this, the car runs perfect, it has no roughness ever, and no hiccups, if there was an injector problem wouldnt the idle be rough or irratic? once the car starts it starts, period. no rough no shake rattle and roll, just smooth!!
help?!??!?
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2003 audi A6
2002 porsche boxter
1989 jeep grand wagoneer
1987 m/b 420 sel
1966 vw type 1
1965 mustang "a" code gt
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  #4  
Old 07-03-2005, 09:35 PM
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Join Date: Apr 2000
Location: eastern NC
Posts: 149
My 380 SE does the very same thing. I believe it is the accumalator. I don't drive the car often so I haven't tried to fix it though it is embarassing when you try and start it hot and it takes a while. Eventually it does fire up.
Mike
1985 380SE 208K
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  #5  
Old 07-03-2005, 09:39 PM
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Location: SoCal
Posts: 1,303
You misunderstand my post - I DON'T think it is the injectors. You are running rich, which would mean lambda adjustment is necessary. Could be your O2 sensor is bad and you are running open loop; but still the engine will be starting open loop, so a mechanical mixture adjustment is in order.

There are also other reasons for running rich, such as a leaky fuel distributor, bad pressure regulator, etc. If you can't make the system pressure checks or are uncomfortable making lambda adjustments, it's time to find a pro.

Steve
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'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7
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  #6  
Old 07-03-2005, 10:05 PM
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Join Date: Jul 2005
Location: lakeland,florida
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gotcha, i would make the adjustments if i had the info, is there a link you know off? i have the 126 manual on cd but i dont see it in there
__________________
2003 audi A6
2002 porsche boxter
1989 jeep grand wagoneer
1987 m/b 420 sel
1966 vw type 1
1965 mustang "a" code gt
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  #7  
Old 07-04-2005, 10:38 PM
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Join Date: Jul 2005
Location: lakeland,florida
Posts: 24
found what i needed to know, ran the duty cycle on pin 3 and i am within the guestimate,( around 40% or so i also found the e.h.a. to be leaking, so i took it off and changed the o-rings and guess what...........just like eveyone else,it didnt work, i still have the same problem but at least i know what i may be up against i will get a new eha and go from there(i guess)

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2003 audi A6
2002 porsche boxter
1989 jeep grand wagoneer
1987 m/b 420 sel
1966 vw type 1
1965 mustang "a" code gt
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