Erratic idle while in gear

Nov 23, 2005 | 09:03 AM

Z300E

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From: Maryland

1993 300E 2.8

Erratic idle while in gear

1993 300E 2.8 w/no ASR - 130,000 miles.

I have an erratic idle that happens only when the car is in gear. The idle seems to be fine in Park and Neutral. What cause the idle to go bad iwhen I put it in Drive?

Thanks!

Nov 23, 2005 | 09:38 AM

shadowgriffen

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From: Boston

is a German Tank

Plugs?

what kinda spark plugs are you using?

Nov 23, 2005 | 09:47 AM

Z300E

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Joined: Mar 2004

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From: Maryland

1993 300E 2.8

Not sure. They were replaced about 30k miles ago by the repair shop. I'm not sure what they used. What would you recommend?

Nov 23, 2005 | 11:36 AM

shadowgriffen

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From: Boston

is a German Tank

tune up

You should have a tune-up performed (spark plugs, disty cap, rotor, wires) more than likely you are running on platinum plugs which are notorious for giving the 124 an erratic/bad idle...

Nov 23, 2005 | 12:03 PM

Z300E

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Joined: Mar 2004

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From: Maryland

1993 300E 2.8

OK. I'll give that a try. Thanks

Nov 23, 2005 | 05:48 PM

AMG_Fred

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Mercedes-Benz w124

Sounds like the motor mounts. The problem goes away while driving right? then it most likely is. It is a $90 part and a 30 minute job for the average. 10 minutes for a speed worker.

Nov 26, 2005 | 02:52 PM

myfirstbenz

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From: Socialist West Coast

95 E320, 19 Ram 1500 Hemi, 21 GLS 580(wife)

I had the same idle problem with my wagon, but my engine mounts looked fine... I changed out my spark plugs to NGK Vpower for 12 bucks and the problem went away... the car had some crappy autolite plugs from a previous owner, I am very happy with the performance and smoothness of this "fix".

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Nov 27, 2005 | 01:11 AM

AMG_Fred

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Mercedes-Benz w124

Was it called the tranny linkage... Well to not have that delay you can start in first gear by moving it to second and then back to drive... I don't know about the not downshifting part though.. And the motor mounts can cause bad idle because the mounts don't support the engine as well so it acts like it is sitting on it with no cushion which causes the vibration.

Last edited by AMG_Fred; Nov 27, 2005 at 01:14 AM.

Nov 27, 2005 | 01:30 PM

#10

12four

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Joined: Nov 2005

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From: Chicago

87 Supra Turbo / 89 300ce

will the trans act slow if the fluid and filter are old i checked the fluid and it looks and feels good maybe i sgould do a flush and get the filter changed.

lol this car is a huge diference from my supra.

Nov 28, 2005 | 01:46 AM

#11

MBHustla858

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i 2nd the motor mounts. if they are collapsed ur motor is sitting on the subframe transfering the vibrations thruout the car. try raising the motor see if it raises. that'll tell you.