S-Class (W126) 1979-1991: 300 SE, 300 SEL, 380 SE, 380 SEL, 420 SEL, 500 SEL, 560 SEL, 360 SEC, 500 SEC, 580 SEC, 300 SD TURBODIESEL, 300 SDL TURBO, 350 SD TURBO, 350 SDL TURBO

Rough idle/cold start in a 1985 380se

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Old Nov 15, 2006 | 01:58 AM
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troylatif's Avatar
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Rough idle/cold start in a 1985 380se

Hi,

I'm new to this forum. I own a 1985 380se and I just recently finished doing a lot of suspension work. After finishing everything and getting to start the car again, I'm finding that it won't idle quite right. When its cold it starts with a lot of trouble and after running really rough for several minutes. Then once it heats up a little bit past 40 deg C, its idle jumps to about 1600 rpm.

When I was pulling the right steering knuckle, i cracked the ABS speed sensor. Since then the ABS light has been coming on. Is it possible that the broken abs speed sensor is causing the idling problems?

Just on a side note, I read a thread here that detailed some problems people were having with the 126s and ABS trouble. Could this be routine maintenance?

Thanks,

-Troy
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Old Nov 15, 2006 | 10:54 AM
  #2  
jhodg5kc's Avatar
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From: Atlanta, GA
Quite a few:)
Could be your OVP has given up..check the 10 amp fuse on top of the unit.

Also, check and see how much voltage you are getting to the air idle valve.

Jonathan
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Old Jan 20, 2007 | 12:46 AM
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85380SE's Avatar
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From: NE Tennessee
85 380SE, 00 Tundra V8 SR5 4wd, 73 Pontiac Grand Ville, 69 Chevrolet Caprice, 89 Pontiac Safari
Join the club... I also have a poorly running 85' 380SE. Started out doing it when it was cold out and when I would start it until it warmed up, but now its gotten to where it is missing more often, even with new plugs. Remains a mystery.

About the ABS - my anti-lock light used to illuminate often when driving.... now it only comes on about once a month... if that.

Originally Posted by troylatif
Hi,

I'm new to this forum. I own a 1985 380se and I just recently finished doing a lot of suspension work. After finishing everything and getting to start the car again, I'm finding that it won't idle quite right. When its cold it starts with a lot of trouble and after running really rough for several minutes. Then once it heats up a little bit past 40 deg C, its idle jumps to about 1600 rpm.

When I was pulling the right steering knuckle, i cracked the ABS speed sensor. Since then the ABS light has been coming on. Is it possible that the broken abs speed sensor is causing the idling problems?

Just on a side note, I read a thread here that detailed some problems people were having with the 126s and ABS trouble. Could this be routine maintenance?

Thanks,

-Troy
Reply

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