Hey everyone. I just got an '05 320 CDI ... fully optioned which is rare in the US for some reason. I got it to complement my '05 E55 AMG .

I had two 1987 W124s a few years ago and those were great cars but had to let them go.

I was wondering if there were any diesel specific things I should check for or replace on the car?

I am going to do the EGR bypass for sure and probably tuning done (Carlson or some other box/mapping). It needs some extra torque I think especially after driving the E55. It'll be my daily driver and the E55 will be my weekend car.

 

Not really any need to turn it into an E55 wanna be as you put it as I will be keeping the E55, otherwise I might as well sell it. Was hoping to give it a little more pep when needed and many people reporting an improvement in mileage with certain tunes/boxes. I don't f* up any of my cars(check my mod list), and I don't whine. Mods come with consequences everyone needs to understand that.

 

Change the glow plugs right away before they get seized in there.

After the EGR delete, and if you use Optilube Boost or another concentrated Cetane boost additive, you will probably have all the torque and power you need.

 

Thank you very much for the advice here. Makes good sense. Haven't tried Optilube Boost before .. will give it a shot.

 

There are some other cetane boosters out there that are comparable, but this one you can buy by the gallon with a pump nozzle on top.

 

The most popular tune for these cars seems to be the green diesel engineering tune as it increases hp and torque, disables egr and increase fuel economy. Use maps over boxes.

Diesel additives like Powerservice help keep the fuel system clean, lubricated and boosts cetane.

If you do your own work and you're new to a diesel these cars are pretty easy to maintain. Check that your fuel filter has been replaced depending on your milage. I can't remember what the interval is but I change my fuel filter every 50 000km they're pretty cheap for a Mann filter.

Also with the glow plugs soak them with WD40 a few times before trying to take them out just to be safe because they can break. You don't necessarily have to change your glow plugs until they set off a code but you could take them out and put antiseize on the threads. Glow plug life will depend on where you live.

Any links to your IS300 build? I was a fan of Toyota's with a 7MGTE, 1JZGTE or 2JZGTE before I got a benz haha

 

If I might pipe in again . . .

I have the Green Diesel tune - definitely worth it
Change the fuel filter every other oil change
It's better to use liquid wrench or a 50/50 tranny fluid/acetone mix than the WD40 - warm up the engine first, soak over night, warm up the engine again and remove while hot - give the plugs a downward tap with a hammer before trying to remove

Power service is good, but Optilube is way better

 

Thanks a lot for the guidance guys.

I am planning to change out all the fluids (transmission, differential, oil of course, brake fluid, Coolant etc) just to be sure. Fuel and oil filter is top of the list and now with your advice the glow plugs. I do all my own work on my cars. I am not afraid of much on W211s at this point since I have done a bunch to my E55 .. only the diesel engine part is more foreign to me on the the W211. I had W124 diesels before but didn't have to do much except the fuel pump leaks and vacuum leaks, those things were bulletproof

I will look into Green Diesel Engineering .. I am still researching the tunes .. some raise the fuel pressure which some consider risky.

I don't have links to my IS300 build unfortunately. I should've documented that better. I tend not to document my builds as I should. I lost interest when I got my E55 and E46 M3.

 

Guys, I was wondering if I could seek some experienced advice here?

I am getting the following error which points to either GPs or GP output stage N14/2:

I have already bought all the replacement GPs already (Beru 5V). Just have not installed them yet (soaked them in transfluid/acetone) . When I measure the GP to head resistance, it measures just 0.8 Ohms on all of the plugs and also on the brand new Berus I bought. So I am thinking it is not a GP issue.

Also while removing one of the glow plug caps, the plastic disintegrated on me. Part Number is A019 545 5428. But I cannot seem to find them anywhere. If anyone has any ideas or alternatives, please let me know. Thanks!



I am wondering if it is common for the glow plug relays go bad at all? I am trying to locate it but it is not very clear where it is located. From the WIS it looks like it is attached to the transmission, but it is quite blurry. I am going to ohm out the harness first to see if it is a wiring issue. Also does anyone have a good way to test the GP relay? The shop method requires dummy loads and current sense loop, which I don't have



Also a pic from the Engine bay (yes I will clean it up later). Looks like no signs of black death yet which is good news! But the leak off pipes look like they could do with some refreshing. Anyone have any good sources for the brass version connectors and piping? I hate to replace them plastic ones. I have seen some available from the UK but not sure if they will fit our CDIs. I believe our injectors are Bosch but I am not sure if ours are odd ball compared to UK ones for example (just like the GP relays).



Thanks!

 

It's very common for the GP controller to go bad. After to you replace the GPs, if you are still getting the error, then swap it out too.

Shop around, because the price of the controller varies drastically, anywhere from $50 to $300 for the same thing.

I watch a video of a guy who repairs them. It looks like about a three hour job if you want to take a crack at it, or just for fun. Basically, a fusel link burns out inside and you just have to solder in a fresh piece of copper.

 

$115.99USD or $155CAD at rockauto.com

 

You are great! Thank you! I searched for the OEM part 6481530279, the cheapest I found was $142 shipped. It is good to know that the sprinters and Jeeps use the same part. At $125 shipped I may as well just buy the one you recommended. I didn't see any for less than $100 though but it's cheaper than what I managed to find.

Any thoughts on the glow plug caps? I might just put heat shrink on it temporarily, but I hate to ghetto stuff like that.

Any time you are in the Bay area drinks on me!

 

I believe your problem is the glow plug controller. Stage output is a problem related to the glow plugs continuing to run after startup.

The glow plug connectors you should be able to get from the dealer.

The glow plug relay is under the intake manifold and you can get it from underneath the car. If i recall correctly you'll need an E8 or E10 socket to take the 2 bolts off. The starter positive connection may be in the way of accessing one of the bolts so just disconnect your batteries to be safe and remove the positive cable if you can't get around it.

Also regarding glow plug controllers. The North American OM648 doesn't use fuseable links in the glow plug controller but over in the UK they use a different style glow plug controller where you can solder in new fuseable links. I cut open my old glow plug controller to try and fix it but I couldn't as its a circuit board with no fuses. Another thing is the glow plug controller from the OM642 does not work in my experience I've tried it and the engines computer gives a no communication with glow plug controller fault. The part I tried was the Dorman 904310 I thought maybe I got a defective part so I exchanged it for another but got the same fault. A lot of parts places have the wrong listing for glow plug controllers on these cars where they either have one listed that's meant for a UK car or one from a OM642. So I'm pretty sure your only option is to get the OEM glow plug controller which is made by BERU part number 6481530279.

 

Thanks for sharing .. much appreciated ... wish I had seen this before ordering from Rockauto ... The Rockauto one is the Dorman 904310. I have requested a return so let's see how that turns out. I have ordered the OE part also, it's quite a bit more at $242 (not $142 as I had said earlier). Thank you also for the tip on the starter motor positive ... the WIS says to disconnect the battery, now I can understand why.

I wonder what it would take to retrofit a UK version of glow plug relay? I have developer DAS, so can recode ... did that for my E55. I guess it is academic at this point as I have already ordered the parts. I need to get this done ASAP so I can get emissions done and register the car. Won't pass emissions otherwise since they do an OBD scan check.

 

That's interesting. I've seen several sites that say the GP controllers are interchangeable.

I would give it a try when it arrives and see if it works before sending it back.

 

Yes, that is what I wrote to Rockauto customer service. I told them after researching further, the product they are sending is likely not compatible and said I would try it but if it doesn't work then I would have to return it. I don't have a lot of time to mess with it which is why I ordered the Mercedes one also. I can send at least one of the two back and learn something at the same time. I'll update what I find.

 

Well just reporting back .. I got the Dorman Glow Plug controller from Rockauto and it indeed does not work. I get the following error:



I will just wait for the OEM part to arrive. Fortunately, I ordered in parallel. This one will have to go back. Too bad ... I was hoping it'd work.

 

Just finishing up on this ... I ordered the OEM part a while ago but was away for sometime for business ... Took me about 30 minutes to jack up the car and replace the Glow plug controller. It was a pain to get in under there .. The GP controller is held on by two Inverse torx bolts that I could remove with an 8mm socket.

After clearing the code, no more issues. Real shame we can't repair the old one and can't use the cheaper Dorman version .. oh well.

 

Re animating this thread...
Now Rockauto has a different controller under the E320 CDI:
RY1528 Intermotor
https://www.rockauto.com/catalog/mor...nid=552&jpid=0

wonder if this has worked for anybody? At $106 I might just try it.

 

That one doesn't even look close. It is probably for a Sprinter Van.

 

As much as I like Rockauto's prices, they have so many incorrect listings on their site, I recently stopped using them. The cost in returns was negating any savings I was getting.

 

Did you have to pay for returns? I have never had to pay for returns for them. The only issue is wasted time for me having to try the part and then print a return label and dropping off at a UPS or USPS.

Thanks to the guys on this forum that gave me a headsup early that this part would not work, this return was super smooth.

I recently bought parktronic sensors from China that were super cheap on Ebay .. I bought quite a few since they were cheap. They ended up not working at all... and they said it may be due to their manufacturing process. They are asking me to pay for return shipping, which is ridiculous. Always be wary of stuff that is super cheap, especially for Benz

 

Yup, they made me pay for return shipping, and as well, they don't reimburse the original shipping. So I was out $50 - $100 for every one of their mistakes! Maybe it's because I'm in Canada - I don't know.

The last time, it happened I was so fed up, so I opened a PayPal dispute. So far the sake of a few dollars in shipping charges, they lost a few thousand dollars worth of my business every year. They didn't seem to care though. At least in the end I have a whole whack of fridge magnets (people who have ordered from them will know what I mean).

 

Just another thumbs up for the Green Diesel Engineering reflash. That was a great starting point for my car, they are also VERY good with customer service. I emailed them on Sunday/Valentines day about a question specific to my CRD jeep motor/flash that I had loaded 18 months prior...they emailed me back after researching my purchase and specific tune an hour later with the EXACT info I needed to make a decision on glow plugs for that little 2.8 liter motor. I've been using ID Parts for most of my diesel parts lately, they too have really stepped up their business and have excellent customer service.

Enjoy that 05' CDI, I've been thinking about getting a second one now that used pricing is lower than VW tdi money. I do still want a 2 door Golf TDI though...with a manual tranny.

 

Thanks for sharing. It looks like your taste in cars and mine are very close. I was looking for a 2001-2005 Golf TDI manual (but 4 door) for the longest time but people were asking silly money for them. I like diesels and I prefer manual transmissions personally. My 1987 300D was the first auto I owned, the second being my E55. This 320 CDI came up and is fully loaded which seems to be rare for a CDI in North America. It came with Parktronic, Trunk closer, keyless go, cooled/heated seats, dynamic seats, rear visors … some of the stuff that I had to retrofit to my E55. So when it came along, the price was a little higher than I wanted to pay (but still a good deal overall I think) and so were the miles but I snapped it up. It is so much more car than the TDI although I think the TDI would be more fun to drive. I am also super impressed with the mileage. I managed to get 40.8 mpg average on a 300+ mile run and believe me I was not gentle on all of it and there was some traffic.

I have been fairly busy with this car, there were quite a few things wrong with the car in terms of stuff that did not work. I fixed the Keyless Go handles, and keyless go knob. Here is a link to the handles: https://mbworld.org/forums/w211-amg/...ml#post6695550

Parktronic didn’t work 4 sensors were not functioning properly - fixed, but be careful who you buy from on fleabay. I had bought some from China and they simply did not work at all.

Trunk closer wiring was all messed up. Someone had tried to resolder the wires and it was a complete hack. I fixed all that heat shrinking the wires properly. The insulation tape was all sticky and falling off.

Glow plug controller was replaced, although I will never need it for anything but passing emissions (getting rid of the CEL).

The fuel sender was leaking. I JB weld coated the sender inside and out and used Permatex ultra on the seals. It seems to have fixed the leak for now. I will be looking for reasonably priced senders on line but am thinking even if I replace it, it will probably leak after a few years so I think I may see how long the JB Weld coated sender holds up.

Side vents weren’t working properly - good old german plastics that break and the vents come apart.

I changed out the climate control controller for a nicer digital one with the rest function.

I have a tune now (not from Green Diesel Engineering). I found someone in Poland (of all places) that could give me a tune that gives 425 Lb-Ft Torque, 220-240 HP, disables EGR and swirl valves. For $100 + $10 programming cable from Ebay, the price is decent. I couldn’t quite justify the Green Diesel Engineering price of over $600 for a tune. I may take the plunge later, but this tune is pretty decent although maybe not quite as good as GDEs.

Right now I am contemplating whether or not to replace the injector seat washers as preventative measure to prevent “black death”. I can see clearly that injector 3 has had experienced it before (based on the fossilized remains of black death on the injector connector) and appears to have been fixed. I am thinking of replacing the rest, but hesitant due to the nightmare stories of people snapping off bolts and damaging injectors.