SL/R107: Won't idle more than a few minutes
02-11-2019, 09:40 PM
#1
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1975 450SL, 1982 380SL, 1995 SL320, 2004 SL500, 2012 C250
Won't idle more than a few minutes
Have a 1982 380SL I picked up after having set around for several years. After finally getting it started, new gas, plugs, distributor cap and wires, it will start, but then stall.
Car starts, idles, fuel pump makes a loud buzzing type sound, the engine begins to stumble then stalls. It will stay running if I hold the accelerator through its "rough surging" periods. These rough periods last about 15-20 seconds, then it will idle by itself again until the next rough period. This happens even if I bypass the fuel pump relay.
New fuel pump, fuel filter, accumulator, warm up regulator. Rebuilt fuel distributor. All fuel lines, both to distributor and return lines, have been blown with compressed air to ensure no blockage.
I've spent close to a year on this issue, even with the help of mechanic friends. I'm lost.
Car starts, idles, fuel pump makes a loud buzzing type sound, the engine begins to stumble then stalls. It will stay running if I hold the accelerator through its "rough surging" periods. These rough periods last about 15-20 seconds, then it will idle by itself again until the next rough period. This happens even if I bypass the fuel pump relay.
New fuel pump, fuel filter, accumulator, warm up regulator. Rebuilt fuel distributor. All fuel lines, both to distributor and return lines, have been blown with compressed air to ensure no blockage.
I've spent close to a year on this issue, even with the help of mechanic friends. I'm lost.
Last edited by Riggmaster; 02-11-2019 at 09:45 PM. Reason: Typo
04-21-2019, 07:19 AM
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1987 560SL, 2007 SL550, 2012 E350, 2010 c300
87 560Sl stalling when reaching operating temperature
I have 1987 560sl, 72k, perfectly maintained. I have a stalling issue. from a cold start the card idles perfectly (or runs) until reaching operating temp (80c) at which time it stops and will not restart until the car sits several hours and is completely cold again. Replaced: fuel pump relay, distributor cap, rotor, crank position sensor...no change. It appears to be losing spark at the time time it shuts off....STUMPED. Any help/suggestions appreciated
Thanks fellow Benz lovers.
Thanks fellow Benz lovers.
04-21-2019, 01:00 PM
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1975 450SL, 1982 380SL, 1995 SL320, 2004 SL500, 2012 C250
I have 1987 560sl, 72k, perfectly maintained. I have a stalling issue. from a cold start the card idles perfectly (or runs) until reaching operating temp (80c) at which time it stops and will not restart until the car sits several hours and is completely cold again. Replaced: fuel pump relay, distributor cap, rotor, crank position sensor...no change. It appears to be losing spark at the time time it shuts off....STUMPED. Any help/suggestions appreciated
Thanks fellow Benz lovers.
Thanks fellow Benz lovers.
04-23-2019, 08:22 PM
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450SL
On an '82 380SL? The only thing close to a CPS is at the front of the engine connected to the diagnostic socket. It doesn't have anything to do with running.
06-27-2020, 05:22 PM
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1987 560SL, 2007 SL550, 2012 E350, 2010 c300
Had the new Crank Position Sensor tested and it was faulty. Ordered a replacement from Germany and it solved the start/stall issue, but immediately developed a miss/sputter after driving for 45 minutes or so. It would run perfectly around town or on the road for about 45 minutes after a cold start. Indy was stumped as well as every mechanic, website I spoke with. Today I adjusted the fuel/air mix 1/4 turn clockwise (Rich) and drove it non-stop for 2 sessions of 70 miles each.... no miss, no sputter.
Before adjusting air/fuel I checked my exhaust to see if the inside of the pipes were oily, indicating rich condition and found them to be dry, non-sooty. Increasing the richness has made it smooth as silk.
Before adjusting air/fuel I checked my exhaust to see if the inside of the pipes were oily, indicating rich condition and found them to be dry, non-sooty. Increasing the richness has made it smooth as silk.
