Hey there, I have a 1987 2.5 Turbodiesel which I am attempting to fix up myself. I bought it about two months ago and have had problems with it. It smokes at idle (a white smoke that I believe is diesel), blower motor is out, passenger side rear door does not open from the outside sometimes and the window has never worked, the glowplug light comes on, but only for about 5 seconds max, and the engine seems to start a lot better if I glow the plugs at least a couple of times. I've tested the battery using my friends multimeter and it shows that it is right on the verge of needing to be replaced. I'm planning on doing that very soon, but in the mean time I am planning on trying to replace some of the strip fuses and trying to diagnose some of the electrical problems before I go out and purchase new injectors and GPs.
I looked at the glowplug testing instructions on Diesel Giant and noticed that the glowplug relay in my 190d seems to be missing a strip fuse compared to the pictures I have seen on the DG website. I was wondering if this is normal for the 1987 190D 2.5 turbo or if the PO has done something odd to my car since some of the interior buttons for the dome light and the rear defroster appear to have been tampered with.

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The strip fuse where I'm used to seeing it isn't shown in that picture. It would be covered by one of the black plastic lines to the left of the main power lug in the glow relay.

Maybe yours is a newer style relay with a circuit breaker.

Sixto
87 300D

If there's no Aluminum Strip fuse on the Left side (In Your Picture)
[where sixto details to look for it]

You've got an Electronically Enabled Pre-Glow Relay.
(If the Electronics sense any Overload or Dead Short the Pre Glow Relay disables itself.)

Almost all of the 2.5 L 5cylinder engines have this type of relay ,whether in
a W201 chassis or the W124.

May of the W201 's OM602.961 2.5 L engines specifications are included in this document:
http://w124-zone.com/downloads/MB%20CD/W124/Index/602_603index.html

Smoking could just be dirty injectors.
The 5 second glow time MAY be related to one or more bad glow plugs.
(Lets not leap to any UNTESTED conclusions.)
(Find and check for "Clean ,Bright and Tight" your Glow Relay's SEPARATE
ground wire [Both of it's ends] and check the cable itself for continuity)
Go To this page:
http://w124-zone.com/downloads/MB%20CD/W124/w124CD1/Program/Engine/602_603/15-4000.pdf
You want B. "With Afterglow."
Look at section 5.
It's claiming too long or too short glow may be caused by:
The engine coolant temp sensor which tells the GP Relay if the engine is Cold or Hot.
OR
The Wiring.

On the below schematic and legend, terminal #31 (Pin #4) is the Ground for the Pre Glow Relay. [Mercedes Ground wires are almost always BROWN]

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__________________
'84 300SD sold
124.128

Thanks for your help. I'm still a complete newbie at doing any sort of electrical work. I've recently moved to a new apartment with underground parking, so unlike my old place, I have no where to do any work on the car since the strata council says no one is to do any maintenance work on their cars in the lot. I'm planning on doing all the work either in the parking lot near my work or at a friends house so I'm planning on putting these pdfs on my ipod and using that for a guide. I'm reading through all these pdfs you've sent me the links to, thanks a lot for that. I'm also trying to read up on basic electrical work so I can sort of get an idea of what I should be doing. I'll probably try doing some more diagnostic work tomorrow as long as it's not raining.