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1987 560 SEC. Will start and then dies after 2-3 seconds. No laboring to initial start but dies quickly. What do I look for?
 

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31 views but no responses! Please someone surely has an idea as to the source of my problem. Here is some additional information: The starting then dying problem occurs in the morning after the car has sat overnight. Yesterday after 10 starting attempts, the engine remained on and I drove the car to work. 3 hours later the car started on the first attempt!. 4 hours later, same successful start.This morning it took 9 attempts to get the engine to remain running. I suspect that I may have a failing fuel pump. Any thoughts would be appreciated.
 

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Seems like a classic choke issue, if it were an old carb car, so fuel enrichment issue for you. I don't know that car but it should simply supply more fuel when the eng is cold, which should be computer controlled, which is told what temp by an RTD somewhere, likely in the cooling system. Being that old I don't know if it'll understand when said RTD fails, so I'd look for it and see if it's working. It should be a black plastic plug attached to what looks like a brass pipe fitting. Again, I don't know your car so that's a typical description of what they look like. Should be in the head somewhere visible but you can follow wires to see where they go. Usually it gets all corroded since it's exposed to the water and that kills 'em, but could be the wire contacts are corroded, or broke.
With some cars you simply give it some gas to keep the revs up for a minute and it's good to go, meaning to get you by for now, or forever if you don't plan on fixing it but the colder it gets the harder it is to keep alive. If so you'd need to resort to a redneck fix I've used; a vac hose from the intake to near your seat so you can give it a boost of carb cleaner, assuming carb cleaner is still flammable these days?
Could also be your car reads air intake temp and if that goes I'd assume it'll default to a lean condition to meet emission requirements, which would likely give similar symptoms.
I suppose it could also be way too rich, but I doubt it. If it was you'd smell the rich fuel stank which is nasty
 

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Seems like a classic choke issue, if it were an old carb car, so fuel enrichment issue for you. I don't know that car but it should simply supply more fuel when the eng is cold, which should be computer controlled, which is told what temp by an RTD somewhere, likely in the cooling system. Being that old I don't know if it'll understand when said RTD fails, so I'd look for it and see if it's working. It should be a black plastic plug attached to what looks like a brass pipe fitting. Again, I don't know your car so that's a typical description of what they look like. Should be in the head somewhere visible but you can follow wires to see where they go. Usually it gets all corroded since it's exposed to the water and that kills 'em, but could be the wire contacts are corroded, or broke.
With some cars you simply give it some gas to keep the revs up for a minute and it's good to go, meaning to get you by for now, or forever if you don't plan on fixing it but the colder it gets the harder it is to keep alive. If so you'd need to resort to a redneck fix I've used; a vac hose from the intake to near your seat so you can give it a boost of carb cleaner, assuming carb cleaner is still flammable these days?
Could also be your car reads air intake temp and if that goes I'd assume it'll default to a lean condition to meet emission requirements, which would likely give similar symptoms.
I suppose it could also be way too rich, but I doubt it. If it was you'd smell the rich fuel stank which is nasty
After researching my problem on other sites, I removed the fuel pump relay, cleaned the contacts and reseated. To date, no more problems upon starting. Thanks for your input.
 

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Your car should have the Bosch K jetronic fuel injection system which is electromechanical. Im not intimate with your car but these all operate the same. There is a warm up regulator, not sure if thats the correct Bosch term but it is what enriches the fuel for a cold start.
 
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