Glow plug replacement questions

[waffles89]

So, I have searched high and low in this forum for this this information; forgive me if it has already been explained someplace else.

I have a 2005 sprinter with 140,000 miles that I recently purchased. I am currently getting P0380 and P0671 which both pertain to the glow plugs. Everyone seems to agree that it is fine to run on 4 glow plugs, but I don't understand how you are getting around the emissions aspect of it. I cannot pass emissions with this code.

On a unrelated note (hopefully) I am also getting a code U0423. It says "invalid data received from instrument." Any tips on that one?

Any and all insight would be greatly appreciated.

Thanks-

 

[Motodisiac]

When I bought my Sprinter one one the error codes called for new glow plugs. I immediately bought Bosch glow plugs but after reading all nightmare stories here I was hesitant to replace them.

Well, I finally got sick and tired from constant check engine light and pulled the trigger yesterday. A day before I sprayed the plugs with some penetrating fluid. After driving for about 40 miles I immediately pulled the wires off (a lot easier than I expected) and all 5 plugs came out without the slightest hesitation. To say that I was relieved would be understatement. Complete project took about 15 minutes. It feels great

 

[220629]

...
I broke the glow plug !
I got it out 1 1/2 turns very slowly and then snap.
...

Sorry to bother you at a bad time, but it may provide helpful information for others removing their glow plugs. There have been reports that indicate there was very little resistance and GP's still broke.

You say "1 1/2 turns very slowly". Was it hard to turn? I tried to highlight needing to move the GP in and out in very, very small increments with the one which I removed that had big resistance. Whether you are turning it out slow or fast, if it binds and there is too much stress it can break. When I first started the in and out movements to my tight plug it was barely moving and took many in and outs to finally turn freely.

Have you called and spoken to Doktor A? I'm curious as to whether there are any tests which can be done to see if you did actually unseat the glow plug seal. I wonder if the cranking speed test is reliable enough?

"Call my Sprinter Hot Line 412-366-6165. Doktor A".
"have a pad of paper handy when you call him"

Good luck. vic

 

[correllbil]

Hi Andy,
I know this is an old post but I have a question abouy heating the head for glow plug removal. I have the head off the engine. I haven't tried to remove the glow plugs yet but the Injectors came out quite easily. Is it possible to heat the head in a pot of water to about 180 degrees then try the plug removal?

Correllbil
York, SC

 

[abittenbinder]

Hi Andy,
I know this is an old post but I have a question abouy heating the head for glow plug removal. I have the head off the engine. I haven't tried to remove the glow plugs yet but the Injectors came out quite easily. Is it possible to heat the head in a pot of water to about 180 degrees then try the plug removal?

Correllbil
York, SC

My ULTIMATE glow plug removal method, which has always allowed easy removal of plugs, is to put the entire head into a commercial parts cleaner/cooker. and remove plugs while head is still HOT.

Find a local automotive machine shop and they will likely have one of these. This machine heats water and detergent and cleans the head on a rotisserie. Works every time and works better than head heated on running engine.

Doktor A

 

[correllbil]

I am going to replace all glow plugs so I decided to do a cold removal of the glow plugs sense I already have the head off. First glow plug came out very easily. It is a Bosch and looks really new. Next went to #5. Broke loose easily turned about one turn then snap! Now I proceed to see why this happens which is why I did it this way (cold). The glow plug came apart at the place where they are swaged into the main body. When I got the plug to turn easily I pulled the plug out by the tip. I see what is my photo 1. I then use my pliers to pull out the body and see my photo 2. I then turn the head on its side and press out the tip and see my photo 3. It seems that what is binding is actually the tip portion of the glow plugs. Andy, should we be sure to have anti seize here too. Will the combustion products not mix with the anti-seize and maybe cause more of a problem? The clamp marks on the tip is where I was putting it back into the body and decided to take it back out.

Billy C
York, SC

The other 4 glow plugs have the Mercedes Benz stamps so I guess they are originals. I guess someone has replaced the first glow plug recently as it looks like new.

 

[Evzen]

I should not have read the forum...kidding, it is very helpful. On the other hand it make s me nervous to replace mine. 150K 2003.
I have installed the modified "Bill's" unit with the external fuses. Non the fuses burned! The glow plug light does not come on after starting the engine, like before. Still on a cold day, I get smoke and it does't run on all 5 cylinders. If the glow plug is defective, should the fuse burn? Or is there another problem. Before starting to replace the GP's for no reason as they are buried and risking breaking one, someone please chime in.I do not have scanner to read any codes. Everything else seems fine.
Any suggestions are appreciated!!
Eugene
Is there a trick to remove the el. connectors from the GP...like the fuel line clips? Do they just pull up?

 

[cahaak]

There is no trick to removing the connector, they just pull up and off, but they are not the easiest to get to. The fuse will only fail if the GP failed in a shorted state. The GP could fail open and then the fuse would be intact, but in fact no current would be going to the GP and it would not be working, that may be the case for you.

Chris

 

[Evzen]

Thanks Chris! It is a start. I will attack it today, it is @60F outside today.
Eugene

 

[surlyoldbill]

Thanks Chris! It is a start. I will attack it today, it is @60F outside today.
Eugene

Eugene, I popped open your old module just now to tell you which GP's you might need to replace, but NONE of the fusable links were blown. If anyone has a quick and easy way to test if a GP is non-functional without removing it, please share.

Fused to ground or drawing excess current will blow a fuse.

 

[whitedog]

Eugene, I popped open your old module just now to tell you which GP's you might need to replace, but NONE of the fusable links were blown. If anyone has a quick and easy way to test if a GP is non-functional without removing it, please share.

Fused to ground or drawing excess current will blow a fuse.

An open glow plug won't work, but will it throw a code on Sprinters?

 

[talkinghorse43]

Does on mine.

 

[Evzen]

So, I did it yesterday!
Before removing them I put 10Amp fuses it to Bill's relay, instead the 30 Amp. 3 were blown and 2 did not. After removing them ( first, the easiest to get to, broke, just the stem came out). I tested them out, and the two , that the fuse did not burn, did not glow. So they were bad inside. our theory prove to be correct. My original relay sensed something wrong.
What a job, not looking forward to do it again. I had to remove the fuel line to the last cylinder, in order to remove the electrical connection.
I cannot believe, that serviceable item like that could not be more accessible, like under the injector cover. The whole job is pretty much done on feel, than what you can see. Some scary moments before and after the first "crack" when they come loose. # 3 was hard to get out and back in. There were no stripped tread debris visible. I put US made glow plugs in from Accurate Technical Services. They are dual coil and I hope they will last longer. Time will tell.
Thank you all very much for you input!
Eugene

 

[surlyoldbill]

So, I did it yesterday!
Before removing them I put 10Amp fuses it to Bill's relay, instead the 30 Amp. 3 were blown and 2 did not. After removing them ( first, the easiest to get to, broke, just the stem came out). I tested them out, and the two , that the fuse did not burn, did not glow. So they were bad inside. our theory prove to be correct. My original relay sensed something wrong.
What a job, not looking forward to do it again. I had to remove the fuel line to the last cylinder, in order to remove the electrical connection.
I cannot believe, that serviceable item like that could not be more accessible, like under the injector cover. The whole job is pretty much done on feel, than what you can see. Some scary moments before and after the first "crack" when they come loose. # 3 was hard to get out and back in. There were no stripped tread debris visible. I put US made glow plugs in from Accurate Technical Services. They are dual coil and I hope they will last longer. Time will tell.
Thank you all very much for you input!
Eugene

Eugene, you'll now be credited with the discovery of the test to find non-functioning glowplugs! If it doesn't blow a low amp fuse, it's probably dead. A 50 cent test if you have a modified module.

So you replaced all 5? How did you get the broken one out?

 

[abittenbinder]

Eugene, you'll now be credited with the discovery of the test to find non-functioning glowplugs! If it doesn't blow a low amp fuse, it's probably dead. A 50 cent test if you have a modified module.

So you replaced all 5? How did you get the broken one out?

That is not the easiest or most accurate test for open glow plugs.

See my old original post for making a simple fused glow plug test wire. https://sprinter-source.com/forums/showpost.php?p=5232&postcount=17

Connect to each glow plug pin socket in the engine harness connector at the glow module, one at a time. Simply brush the clip you would normally clamp to the battery + post, across the + post, for each glow plug pin test.

Pins are numbered on back side of plug with an accurate glow plug location.

A strong, harsh spark (if you're quick) or a blown fuse (if you're slow) indicates a failed shorted plug.

A gentle brush of sparks ,and no blow 20A fuse in 10 second, indicates a operating glow plug.

NO sparking indicates a open circuit glow plug.

Easy to see in strong daylight.

Doktor A

 

[surlyoldbill]

Probably best done in the dark instead of high noon on a sunny day.

 

[Evzen]

Bill, yes I replaced all 5 , got the broken out. How it broke was my fault. Someone suggested to hit them pretty hard first. I used smaller socket for that , but small enough...! Pretty scary to break the first one. I did not to hit the rest of them.
Thanks for your modified unit, pretty simple test from now on. It is like 5 testing fuse links in one. Fuses are cheap
Eugene

 

[surlyoldbill]

Bill, yes I replaced all 5 , got the broken out. How it broke was my fault. Someone suggested to hit them pretty hard first. I used smaller socket for that , but small enough...! Pretty scary to break the first one. I did not to hit the rest of them.
Thanks for your modified unit, pretty simple test from now on. It is like 5 testing fuse links in one. Fuses are cheap
Eugene

I like Dr Andy's test, too.

 

[correllbil]

Ok, here is a good question. Does the glow plug actually glow when it is activated? I think I will lite one up and see if it gets hot enough to "glow".

Billy C.

 

[Altered Sprinter]

Ok, here is a good question. Does the glow plug actually glow when it is activated? I think I will lite one up and see if it gets hot enough to "glow".

Billy C.

The answer is yes.

One of the quirks of the sprinters electrical system is a fully blown glow plug,the glow light showing on you dash plus a EDC light results over voltage. not always the cause but well known on a diagnostic test from MB
Richard
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