glow plug light comes on after I start car?

[NickMendoza]

92 300D 2.5

I turn the key- all lights come on in cluster (no glow plug light).

The glow plug light does not come on.

After I start the car = the glow plug lights turns on and stays on.

help--

Thank you

Nick

[pberku]

You have at least one burnt-out Glow-Plug. Replace the Defective Glow-Plug(s) and your Glow-Plug light will work normally again.


Phil

[NickMendoza]

How can I tell which glow plug is the one?

Thank you

Nick

[The Warden]

The quick-and-dirty way is to unplug the plugs from the wire, and hook a test light to the positive terminal on the battery. If you touch the tester to the "hot" side of the glow plug (where the wire attachs) and the light lights up, the plug's probably good.

The proper way to test them is to get an ohmmeter and put one lead on the part where the wire plugged in, and the other on the outer threads (this should be ground). If your meter shows 2 to 3 ohms or so, you're good. Infinite resistance or 0 resistance indicates a bad plug (either burnt out or short-circuited so that it sucks up power but doesn't heat up).

Hope that helps some..good luck!

[NickMendoza]

Dealer said to replace them all. I am only going to replace the ones that do not work.

I went out to buy a meter. Saved quite a bit of money.

#1= .02
#2= no reading
#3= .02
#4= .02
#5= .07

I am going to replace the #2 plug. I am sure that will fix the problem. This is why therer is an almost at the header.

Thank You

Nick

[sixto]

Looks like #5 is telling you something.

If the 602 is anything like the 603 turbo, you have to pull the intake manifold to replace the glow plugs. Consider the effort involved and the number of brittle injector line retainers that will break before deciding to replace only one glow plug.

Sixto
95 S420
87 300SDL
83 300SD ... $1100, see cars forum

[pberku]

Hi Nick,

As the previous member Sixto suggested, "Replace them all". When one glow-plug goes, the other ones are usually not far behind.

Save yourself the trouble and aggrevation by replacing them all now, and be free of of more glow-plug problems for at least the next 100,000 Miles.

Phil

[P.E.Haiges]

Nick,

Normally I would only replace the one bad GP. But if there is a lot of time necessary to remove other parts to get at some of the GP, I might replace the ones that are hard to get at with new ones and use the older ones in the places that are easier to get at. I don't think you have to remove the intake manifold to get to some of the GP.

I haven't found it true that if one GP fails, others are likely to follow. They are sort of like light bulbs, you just replace the ones that are burned out. In my '80 300SD, I replaced one GP many years and thousands of miles ago and the other GP are still working. I always carry a spare just in case another GP fails. They are easier to replace in the 61x engines than in the 60x engines.

Isn't that like a dealer to say to replace all your GP when only 1 or 2 are bad.

P E H

[NickMendoza]

I am going to take a risk. #2 is right there. I will replace it and hope for the best.

Location is the reason why. If I have to take apart the intake= I will replace them all.

As you can see- it is within socket reach.

Thank you to all

Nick Mendoza

[Rick Miley]

PEH, your 1980 300SD also does not have the afterglow feature. I'm pretty sure the 92 does have it, and plugs just don't last as long on afterglow equipped engines. Keep that in mind when you tell people to replace only one plug.

[NickMendoza]

I have fixed the problem. It was the #2 glow plug. I could do it without taking off the intake. All the others tested ok. If another one goes out I will take off the intake and replace them all.

Thank you to all

Nick