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Vintage Cars/1985 Mercedes 500 SEL


QUESTION: Vehicle was purchased at auction, 125,000 miles, sllegedly great vehicle but not driven in two years.  Drained tank, replaced fuel filter, fuel pump, Old one no good)  replaced fuel relay and flushed injector lines to remove old fuel.  Vehicle now will start, idle and rev.  Upon start will run for only several seconds.  Although it dies it will repeatedly start and will run well - as long as I feed it a trickle of fuel through the intake.  I have checked the incoming fuel line from fuel pump and it seems to maintain substantial pressure anytime the engine is cranking.  Help   Thanks

ANSWER: I would replace injectors or at least make sure the spray pattern in sufficient
also check air flow sensor, control plate, Cold start valve . rest and warm pressures ect...
the Kjet requires a systematic approach to diagnose.  Send me an email and I will send you all the testing procedures

---------- FOLLOW-UP ----------


Thanks for the reply. I have all of those things on my list, but hoped the scenario I gave would identify a logical remedy.  Apparently, there is nothing logical about this car.  I would be thankful for the testing precedures you outlined as well as what the results should be.  As I am on Social Security, this maybe an expense I can't afford.  One of the web's suggestions was the replacement of the fuel cut off sensor and have no idea if that is a feasible.  In the "old" days, the problem would have been of simple fuel starvation or failure of the carburator to do its job.  I am thankful for any details you can provide.  Thank you.

so true, old cars , gas and air = running, not so on these Kjet cars , you will need some pressure gauges and a test meter as well as a lot of patience./  You mentioned you replaced fuel pump - these cars require a specific pump for pressures - did you replace with OEM spec unit?
In any respect
I cannot attach the file to this, but if you email me at I will be glad to send it to you

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I can answer questions on W110/W111/ W114/ W115 /W(R)107/W123/W126 , and Finny Mercedes models 1962-1985. I have rebuilt many of these cars and have problem solved many issues. I have access to much of the technical data and have detailed instructions on fixing the most common issues. Vintage US 1950-1989 and other foreign cars as well If you are going to ask me about car value, please provide ample information on service history, rust issues, and current "needs". Pictures are helpful. Disclaimer on value - I can only give you data on what the market is bringing, and may not be what you want to hear!


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