Glow Plug/CEL Lights On - How Long Can I Delay Repair? - PeachParts Mercedes-Benz Forum

christyb · #1 05-02-2009, 03:11 PM

I have a 1999 e300 TD, about 130,000 miles.

On Thursday after starting up as normal, the Glow Plug and CEL lights came on. I drove about six miles that day.

Yesterday, it started "clunky" and then the GP and CEL lights back on. I drove about 5 miles and then parked. After a couple of hours when it was time to go, it started up without the "clunk", GP & CEL lights on, and drove home 5 miles.

I know it needs to go into the shop but how long can I delay this repair?

Tomorrow I have to drive about 20 miles, let it rest, then another 20 and let it rest and then 40 back home.

Am I setting myself up for being stranded tomorrow?

Am I setting myself up for a much larger repair?

Can I milk this but drive differently (slower speeds, etc...)?

I'm sure to some of you this is an extraordinarily stupid question, but I know 1/2 more than nothing about cars!

Thanks!
Christy

cessna5354 · #2 05-02-2009, 04:15 PM

You can put this off, but it will be dependant of ambient temp. for starting. It will also be increasingly more strain on your starter. I have just gone thru same thing, Diff. starting, lites on, @ 210K miles I bite the bullet and completed.
I tested the resistance @ the plug and 2 GP's indicated bad. Pulled all 6 and 3 were DOA, not sure how far below "new" others were, when I lite them up with jumper cables.

I would do this repair when funds and time is available. But not more than 3 months (arbitary).

Be very, very, very (ElmerFudd) patient with the removal, and you will be much better off with this in your past.

Best of Luck & many great posts in Archives.

Gary Pasternak

Diesel911 · #3 05-02-2009, 05:45 PM

Since it is sometimes difficult to get the Glow Plug/s out without breaking them you might want to read a head on what to do and plan to have time available and a another vehicle to get you to work if the worst happens.

christyb · #4 05-02-2009, 06:06 PM

Quote:

Originally Posted by Diesel911

Since it is sometimes difficult to get the Glow Plug/s out without breaking them you might want to read a head on what to do and plan to have time available and a another vehicle to get you to work if the worst happens.

The most I will be involved in the repair is taking the car to the mechanic and writing the check!

The "worst" you are referring to is the actual repair and not driving around in the meantime - correct?

It will most likely be at the mechanic in 2 weeks.

Thanks,
Christy

cessna5354 · #5 05-02-2009, 06:21 PM

Chistyb,
The worst would be if the GP's sieze in the head and break during removal. The head is aluminum, GP's are steel, with age, heat, corrosion, dissimiliar metals, carbon etc. They can be on occasion extremely difficult to remove.
I cannot emphasis enuff patience, lube, and a rapping & tapping of the wrench. Not unlike the raven. Very low impacts will allow lube to engage the threads.

Good luck,

TMAllison · #6 05-02-2009, 08:29 PM

Hi Christy - You could try cycling the key twice on the first start of the day, and then raising the rpm's to 1000-1200 a couple seconds after it starts, to help smooth out the rough idle while it warms up. Find the rpm where the cold engine sounds happy while it warms up. The idea is to create enough heat in the Cyl with the bad GP so that combustion occurs normally from the heat generated via compression. In SoCal, it ought to warm up pretty quickly.

Try to get it taken care of within a couple of weeks. In the mean time, after its at operating temp and running normally, don't be afraid to give it some heavy throttle every once in a while to help clean out any carbon being built up during the rough starts.

BioPOWER · #7 05-02-2009, 09:18 PM

Quote:

Originally Posted by christyb

The most I will be involved in the repair is taking the car to the mechanic and writing the check!

Please take this job to someone who's seen an E300 before, ie. dealer or a Mercedes diesel mechanic.. even though replacing glowplugs seems simple, it's also extremely simple to screw it up.

Removing and/or machining the head will be much more expensive than having the dealer change the glowplugs.

christyb · #8 05-02-2009, 09:51 PM

TMAllison - I have not forgotten about the Rhubarb Pie, I have just not been in the area!

Thanks for the advice, I will make sure to follow it and hopefully the car will be no worse for the wear (or me stranded) by the time I fix it in two weeks.

BioPower - I am going to take it to German Imports in San Juan Capistrano, CA, "20 year experience, owner/mechanic, German trained, complete service & repair". When I have been there, 95+% of the cars there are Mercedes diesels and their personal cars are Mercedes diesels.

I have taken it there twice before - 2 oil changes and a brake job.

If someone has any feedback about the shop that would be appreciated.

Do you really think it's best to take it to the dealer? They all were replaced about 4 years ago at the local dealer and it was expensive. If I did take it to a dealer I would take it to a different dealer this time but I'm sure that they are even more expensive!

Thanks,
Christy

Diesel911 · #9 05-02-2009, 11:00 PM

Quote:

Originally Posted by christyb

The most I will be involved in the repair is taking the car to the mechanic and writing the check!

The "worst" you are referring to is the actual repair and not driving around in the meantime - correct?

It will most likely be at the mechanic in 2 weeks.

Thanks,
Christy

Ask your Mechanic if he knows it is possible for the Glow Plugs to be stuck and break off when he tries to remove them. If not he might not know some of the possible steps he could take to prevent it from happening.

Also keep in mind that if 1 or more Glow Plugs breaks off it will be more work/money for the Mechanic.

If even 1 breaks of in the Head the Mechanic will have the choice of trying to drill it out himself and face the possibility of damaging your head (if he damaged it he would be responsible for the damage).

Or, he play it safe and remove your Cylinder Head (which is something he can do without risk while at the same time making more money for himself) and send it to a Machine shop.

If you where the Mechanic which would you pick: Be safe and make more money or try to save the customer money and maybe take responsibility for damaging the Cylinder Head trying to drill out a Glow Plug.

The above is why some people choose to do it themselves.

TMAllison · #10 05-02-2009, 11:29 PM

The important factor is if they have any expirience with the 95-99 and 04-09 diesels that use the longer, thinner style GP's. They are more delicate than prior versions and can twist off while attempting removal.

Here on the forum, most folks will soak them with penetrating oil for a couple of days prior to changing to help loosen them. The threads can sieze beacuse of dissimilar metals and they can become bound up with carbon deposits at their tips. Warming the engine to expand the metals, and then immediately spray freezing the GP to shrink it/them prior to attempting to remove seems a reasonable precaution. Destructive analysis on old GP's (held in a vise) suggests they twist off right around 80-90NM of force. Applying less force seems wise.

Some folks (me, and a few others) are proponents of only replacing the bad one.....why tempt fate removing a perfectly good one.....its still good, right? Wouldn't you feel stupid if a working GP snapped off and cost $2,500 to remove? Others will have a different opinion.

There is an extraction tool kit MB produced for the 606 engine. Indies wont have that; many dealers wont have it either because of cost of tool vs. amount of times it needed as diesels aren't so common.

Just ask your mech if they are familar with the problem of them twisting off and go from there.

DO ask for BERU replacement GP's, not Bosch. Beru's were OEM and have a slightly larger nut for the socket to grab. Beru's are $37 ea on this site. Bosch is $25. Your mech will be double that i'd guess.