I went out this morning to start the CDI. Low of 19F last night. My car has the key where you just turn it once and then let it go and supposedly the car cranks for as long as is necessary to start the car, but stops after 10 seconds to be kind to the starter. Anyone know what this system is called?? Anyway, it glows (all 6 glow plugs just replaced 1 month ago) and then turns over for 1 second and then kills. I do this 6 times before the car starts roughly. No check engine light and no malfunction warnings. I called the dealer to see if this was what I should expect from a benz diesel and cold-weather starting time. Service manager said no and I have an appointment for Wed. Trying to do some sleuthing between now than then. Any thoughts or opinions?

 

Glow plugs would have been my guess but since those are OK, I would guess you don't have good diesel for low temperature?

If the car is OK and you first wait till the pre-glow indicator turns off (at very cold it takes more than a couple of seconds), the car should start effortlessly. 19 F is not cold at all if you have 0W or 5W engine oil and the diesel quality is good for low temperatures.

 

With 5 years of dieseling in MN, I have never had an issue with inadequately blended diesel fuel (knock on wood). It has 5W Mobil 1 synthetic in it. The glow plug does not stay on any longer that it did during the summer. I agree, 19F is not cold (for Minnesota, at least). My Jetta TDI started fine at -10F w/o even using its block heater.

 

I drive a 2006 CDi and I owned a 1999 Jetta TDi (series 3) and had no problems with either in freezing Toronto. In the winter I tried to fill up with Sunoco Gold diesel whenever I can.

The way your CDi is behaving is not normal.

Try using the block heater.
Use 0W40 synthetic (as recommended by MB).

 

When turning the key, are you pausing at the "ignition on" position to allow the glow plugs to bring the cylinders up to temp before continuing to the "start" position? The E320 CDI engine doesn't have a fully automated start sequence (like our Touareg V10 TDI), and in cold weather, you MUST pause for a couple of seconds to let the glow plugs warm things up.

When I forget to do this (usually the first cold start of a winter season), the car punishes me by starting hard, running roughly for a moment and putting out white smoke from the partially-burned fuel.

 

I believe I'd assume "all glow plugs replaced 6 months ago" did NOT solve whatever problem you had then.

 

I do pause at the glow step when turning the key and wait for the glow plug light to go out. The glow plug problem was a glow plug circuit fault code caused by a bad #6 plug. That problem has been solved. Car starts at 20F, but puts out blue smoke and runs rough for a few seconds. The glow does not seem to be long enough in my opinion. Glow plug controller issue? Bad temp sensor for the plugs? The problem initially mentioned has not reappeared, but, again, it has not been that cold yet.

 

If it really does not show longer pre-glow than at summer, it really could be an issue with the glow plug control.

The light itself would go away once you start even if the car would keep glow plugs on but there should be a noticeable difference when first switching ignition on (nothing like on old diesels though, even at extreme cold, the pre-glow period is still pretty short).

I did not go and read documents but does your ambient temperature read right, and the engine temperature? Not sure which temp sensor the system is actually using when deciding on the glow period.

 

Where are you buying 0W40 in Toronto .? It's very hard to find ...

 

I would say for this car you are better off running the Mobil 1 5w-40 as it is designed specifically for diesels.

 

For Canadian diesels MB suggested the following synthetic oils:

0W40 Mobil One for the straight 6 turbo and
5W49 Mobil One for the Bluetec V-6 turbo

 

I found some in the Canadian Tire at Sheppard and Leslie. It is not difficult to find. Mobil One synthetic.

 

First of all, please don't "hijack" my thread. Second, wouldn't start again last night. Ambient temperature seems to read correctly. On first start, it cranked for a long time, but didn't start. Second start, cranked for a long time, but not quite as long. Third time, cranked over as it would normally and then died. this continued for a few times. I decided to override the glow plug timer by glowing it 6 times in succession without trying to start. It then started, but VERY rough with a cloud of blue smoke out the back.

 

What happened at the dealership? No diagnosis?

 

I couldn't get the problem to recur (because it was warmer) so I cancelled the appointment. I want it to really act up for them. That will result in an easier diagnosis on their part- if anyone actually does diagnosis anymore, as opposed to just throwing parts at a car and hope it fixes the problem.

 

If your car is a 2005 then it is still under warranty. You should take your car in to the dealership so that it goes on record that you have a problem with cold starting. When the problem becomes permanent you can then claim.

 

You should wait till the temperature is sub-zero and leave the car with the dealership overnight in the open.

 

Done. Leavinging it overnight tomorrow. My vehicle has 85k miles on it so it is out of warranty

 

To answer your key question, its called tip-start

 

OK, here's the verdict. The CDI needs a new fuel rail. Evidently it was losing fuel pressure. $800 for the part. They want to charge me 8 hours of diagnostic time plus 3 hours to do the job. I am so pissed off. They did 8 hours of diagnostic time without getting any sort of approval from me.

 

My question would actually be why a diagnosis like that took 8 hours? It should have been a relatively simple procedure with all of the equipment they have.

On a side note, when you drop a car off for a diagnosis, you are authorizing a diagnosis, unless you specify a maximum time allowance. The problem with doing that is that they may just always charge you for whatever you said would be the maximum.

 

Hey Myco,

Which dealership is that? Publicize the name so we know to avoid it.

What is your name short for? I was thinking of Mycoplasma, Leptospirosis and the lumbar-sacral discs. Are you medical?

 

I would ask them to drop the 3 hour labor charge and just bill you for the (still unreasonable) 8 hour labor charge with the part installed.

 

There also remains the issue you have new glow plugs you probably didn't need.

 

As to the max. time allowance. I had a discussion with the service rep. when I dropped the car off that they would spend about an hour of diagnosis time and then would contact me. As far as being relatively simple, most technicians know very little about how to diagnose a car. They rely on the computer systems, i.e. the fault codes to tell them what to do. There were no fault codes so everyone was stumped. As for mycoleptodiscus, I used to be a scientist doing research on fungal genetics and plant pathology, so basically a plant doctor Mycoleptodiscus is a fungus genus name. I know how to think and solve problems which is why it frustrates the hell out of me that people are no longer taught how to think (solve problems) in school (I'm an 8th grade science teacher now- I make them think- they engage in real problem solving). Anyway, after talking to MB for a considerable amount of time, they think the fuel rail pressure is leaking down (something about a pressure valve in the rail leaking that holds pressure in the rail when the car is sitting), but they have no way of testing this because the pressures are too high- they can't put a gauge on it. They just don't think! I suggested just packing the fuel rail in ziplocs with ice (probably a $20 diagnostic process) and salt and seeing if that gave symptoms. They didn't want to try that. Uugh.

On the bright side, my dad went to H.S. and college with the owner of the MB dealership. I haven't used this resource until now. I emailed him and got some serious action including the statement that "you will not be charged for anything that does not fix the car" The service manager went so far as to say that he didn't think he could fix this problem at absolutely no cost to me. I replied that I didn't expect that, just to be treated honestly and fairly. We had a long discussion about an earlier glowplug issue as well in the context of honesty and establishing trust. The salesman sold me the car and told me the glow plugs had just been replaced by the dealer. In fact, just #1 had been done. One month later, #6 failed. I was completely baffled by the #6 glow plug circuit fault code, figuring maybe it was a problem with the glow plug harness, but it all made sense once we looked back on the repair records. In my opinion, they cut corners and turned around a car they knew was in high demand and would be off the lot in a week. At the time, the dealer agreed to pay labor for the additional plugs and I agreed to pay for the 5 glow plugs. Problems; the service rep. who allowed 8 hours of work w/o consent, the salesman who lied to me, the used car manager who made the decision to replace only one glow plug and cut corners and the service manager who offered only to pay labor on the glow plugs and not pay for the whole job.

As frustrating as this has been (over a week now) the dealer is being just fabulous now. Very helpful and conciliatory and listening to me and my concerns. A lesson I have learned is that you need to advocate strongly for yourself (this doesn not mean being an ***). Push hard and ask the tough questions. Communicate clearly, preferrably in writing (email) as then you will have a written record of events. Also, it helps to have connections