95 e300d glow system questions - PeachParts Mercedes-Benz Forum

connerm · #1 02-28-2008, 07:57 PM

202,000 miles. Car started fine at 3:00 p.m today after sitting outside. Glow light came on like normal, barely turned the key and it fired right up. Glow light went out and I was on my way. Took a short trip and parked. An hour later I went to start it again. No glow light. I cranked it, and it started fine, but probably because the engine was warmed from the 3:00 start. Glow light came on after car was started and went out about 30 seconds later. Did this once more before I got it home. I have the block heater plugged in, although its in my garage. Plugged in so I have a better chance of starting it tomorrow morning.

New wiring harness 90k miles ago. Getting 29 mpg steadily. Getting easy starts, no smoke and smooth idling. The 10 amp fuse on the OVP relay appears good. The gp relay doesn't have a visible strip fuse. Moving the key to position 2 I hear clicking and things under the hood. I'm by myself so I can't really tell whats making the noises.

Glow plugs are the ones that came with the car when I bought it 100k miles ago. No issues with starts so I haven't messed with them.

What would cause the glow light to not come on at key position 2 and then illuminate after starting. Is there anything easier than checking the glow plug resistance? I don't think its glow plugs because it was so sudden. What should I check next?

Matt L · #2 02-28-2008, 08:58 PM

A failed glow plug relay will do this. I don't know if blowing the (internal) fuses will.

connerm · #3 02-28-2008, 09:05 PM

Do you suppose I have any chance of starting it without any glow plugs? Any way to test the gp relay? Is probably original.

TMAllison · #4 02-29-2008, 12:33 AM

Checking the GP's and realy is easy with a multi meter.

Go to dieselgiant.com and follow the procedures he outlines for the W123. It is applicable to your 606.910.

WINGAS · #5 02-29-2008, 12:37 AM

Well, nothing is that easy on the 95 without the intake removed. But once you remove it, they should show around .6 ohms.

TMAllison · #6 02-29-2008, 12:43 AM

You test resistance from the relay harness generally.

engatwork · #7 02-29-2008, 05:59 AM

Removal of the 95 e300 manifold is not that hard.

connerm · #8 02-29-2008, 06:24 AM

Did some initial testing with a rookie multitester which is indicating one of the gps is bad - showing much more resistance than the 5 others. Main strip fuse is good. Thanks for suggesting the dieselgiant page. Will get a good multitester and test battery, relay and wires and report back. Car just started fine although no glow light until AFTER it started. Block heater plugged in sitting in my garage all night. Probably around 45 degrees in there - 20 degrees outside. Stinks to think about the gp removal on this engine. Really stinks.

connerm · #9 02-29-2008, 08:48 AM

Don't mean to hijack my own thread, but I'm anticipating a glow plug project, sooner or later. I have read probably all of the threads here re: stuck glow plug and I plan to approach the job with the following tools: right angle impact driver, carbon cutter, and some brand of freeze spray. Comments are especially appreciated now, before I get into it.

http://www.newwoodworker.com/reviews/ridgid82233impctdrvrvu.html
http://www.slip2000.com/carboncutter.html
http://www.ferret.com.au/c/Loctite-Henkel-Australia/Loctite-presents-new-Freeze-and-Release-lubricant-n672370

pimpernell · #10 02-29-2008, 10:54 AM

Quote:

Originally Posted by connerm

Don't mean to hijack my own thread, but I'm anticipating a glow plug project, sooner or later. I have read probably all of the threads here re: stuck glow plug and I plan to approach the job with the following tools: right angle impact driver, carbon cutter, and some brand of freeze spray. Comments are especially appreciated now, before I get into it.

http://www.newwoodworker.com/reviews/ridgid82233impctdrvrvu.html
http://www.slip2000.com/carboncutter.html
http://www.ferret.com.au/c/Loctite-Henkel-Australia/Loctite-presents-new-Freeze-and-Release-lubricant-n672370

The impact driver, with 700 inch lbs. of torque, might be a little on the heavy side as it pertains to plug breakage. Beru lists their plug breakage figure at 45 n/m. Other posters on this forum have indicated that the plugs can go beyond that figure without breaking. As for me, when I removed all 6 plugs in my car, I used a n/m torque wrench, to stay within 5-10 n/m of the break figure given out by Beru. All the plugs came out, with the help of a lot of PB Blaster and a product called Freeze-Off, both of which are available at most auto chain stores.

700 in.lbs X 0.113 = 79 n/m

Inch Pounds x 0.113 = Newton Meters

connerm · #11 02-29-2008, 11:38 AM

Of course I have to check out the tool first. I'm not sure if you get all 700 in/lbs when you pull the trigger. I'd like it a lot better if there was a clutch on the chuck. Right angle driver/drill by dewalt might be better.

connerm · #12 03-01-2008, 02:40 PM

GP resistance
cyl 1 is .9
cyl 2 is 1.1
cyl 3 is 1.0
cyl 4 is .9
cyl 5 is 1.2
cyl 6 is open - no resistance

Battery
12.6 no load
10.3 with starter load
14.3 after starting

GP Relay
12 volts at each pin when key moved to position 2
7.7 volts after 30 seconds or so

Looks like my glow plug light is coming on for a reason, and that reason is a bad gp #6. Will try this myself having read the posts on this forum.

By the way, it started with no problem with no glow plugs after sitting overnight with the block heater plugged in. I know this because I tried to start it with the gp wire harness plug removed from the gp relay.