proper Idle rpm for 85 300d ? - Page 2 - PeachParts Mercedes-Benz Forum

#16 06-26-2007, 11:35 PM

Quote:

Originally Posted by Brian Carlton

Agreed.

The SD is at 725. It's a good speed and doesn't tend to tow you at stoplights.

I'd think that 600 would give you a case of the "shakes". That's very slow for a five cylinder.

I agree that 600 rpm is a tad low, it shakes slightly when it's cold, but it's smooth once it warms up a little, after about one minute with the post-glow (it's been running pretty smoothly ever since I replaced the IP). That's just where my indy left it, I'll probably bump it up a little in the fall so I don't have to play with the "throttle" for winter starts.

quickster · #17 04-10-2008, 10:56 PM

I cannot find the trimming plug on my 300D. It's idling at about 550 and shakes pretty bad. I've been reding other posts, but to no avail. thanks

winmutt · #18 06-30-2008, 08:44 PM

How exactly could this affect idle? The only way I can see this altered the idle is if the rack sensor on the IP was more than just a sensor.

Brian Carlton · #19 06-30-2008, 08:49 PM

Quote:

Originally Posted by winmutt

How exactly could this affect idle? The only way I can see this altered the idle is if the rack sensor on the IP was more than just a sensor.

The OM60X engines have the EDS system with a computer controlled idle. The 617 doesn't have such a system.

winmutt · #20 06-30-2008, 09:06 PM

Not according to what bstef said in the replies above. He is claiming that this trimming plug is altering the idle speed. How else could he be doing it? I really wonder if the "rack sensor" on the 85 IP is really alot more.

Brian Carlton · #21 06-30-2008, 09:31 PM

Quote:

Originally Posted by winmutt

Not according to what bstef said in the replies above. He is claiming that this trimming plug is altering the idle speed. How else could he be doing it? I really wonder if the "rack sensor" on the 85 IP is really alot more.

Well, you could be right with the '85. The transition year might have some of the same equipment as the later models.

winmutt · #22 07-01-2008, 07:55 AM

Forced brought up a good point that this guy was more likely changing his tach than his engine speed.

#23 07-01-2008, 07:57 AM

Right. The rack position sensor has no method of moving the rack on its own, its just an inductive sensor. He is more likely just altering the tachometer calibration.

Diesel Dan · #24 07-01-2008, 01:30 PM

Quote:

Originally Posted by quickster

I cannot find the trimming plug on my 300D. It's idling at about 550 and shakes pretty bad. I've been reding other posts, but to no avail. thanks

The trimming plug on my '87 300D is in the engine compartment near the fuse box and brake master cylinder on the driver's side. Maybe yours is also in that general area?

Tymbrymi · #25 07-01-2008, 02:29 PM

Quote:

Originally Posted by Bstef

[IMG] The dial is a trimming plug for idle control. Turning the knob should raise or lower idle in 25 or 50 rpm increments.

Dunno about anyone elses model. It works on mine...

Sounds exactly like the system used on the 86/87 OM60x engines (in the usa at least). The OM602 used in the later 300Ds don't give you the option to adjust it. Is there something where the rack dampener pin is normally?