Tuning a CDI as Preventive Maintenance - PeachParts Mercedes-Benz Forum

shertex · #1 09-02-2020, 11:28 AM

I'm still mulling over tuning my CDIs. While I have no performance complaints, I guess I'd be happy to get a bit more power. One of my main motivations, though, would be to head off future maintenance issues. The two that come to mind are EGR and the swirl flaps. Are there any other items that come to mind that can be dealt with preemptively via a tune?

awsrock · #2 09-03-2020, 08:28 AM

Do you know what tuner you are going to use? It seems as though some of the well sought after tuners of years past are not offering tunes anymore. Perhaps they are but aren't listing them? Either way there are still many others available.

I too am interested in an answer as I will be getting a tune at some point for my new to me CDI. I want that EGR gone, it smokes out people any time I downshift and it makes me angry...I have a tuned 603 that doesn't smoke at all!

If you are willing, it seems an upgraded intercooler will allow you to make the most of a tune as the stock one is inadequate for much more than stock power.

GregMN · #3 09-03-2020, 10:35 AM

I have heard tell of people doing this on the 642's to eliminate EGR system, regeneration system, and then replacing the exhaust filter with a pipe. That was cheaper than fixing any one of the various problems with those systems. So, you are on the right track for more trouble free long term ownership.

shertex · #4 09-04-2020, 03:11 PM

Quote:

Originally Posted by awsrock

Do you know what tuner you are going to use? It seems as though some of the well sought after tuners of years past are not offering tunes anymore. Perhaps they are but aren't listing them? Either way there are still many others available.

I too am interested in an answer as I will be getting a tune at some point for my new to me CDI. I want that EGR gone, it smokes out people any time I downshift and it makes me angry...I have a tuned 603 that doesn't smoke at all!

If you are willing, it seems an upgraded intercooler will allow you to make the most of a tune as the stock one is inadequate for much more than stock power.

As far as I can tell Jeff Robertson (Rocketchip) is still doing tunes. He is first rate and reasonably priced...tuned my 98 E300 number of years ago. BUT you either have to take the car to him OR pull the ECU and send it to him (unless he's changed his approach).

There are some other tuners that provide software to pull the data from the ECU. You send to them, they modify the file, send it back and you upload it.

awsrock · #5 09-05-2020, 10:37 AM

Well that's good to know that Rocketchip is still doing it. I think some places have stopped advertising but might still tunes if you email them. Seems most of them require you to send in the ECU but I have seen a few that can be done via OBD2 port. I probably won't start shopping for a few months, or even until next spring, so I am interested to see how your experience goes! I still have some other issues to sort out first.

chronometers · #6 09-05-2020, 12:40 PM

You can minimally eliminate the EGR valve using this bypass:

EGR AGR valve emulator for Mercedes Benz CDI OM611 OM612 OM646 OM647 OM648

I bought from same seller 2 years ago and have not had any EGR issues (that is a performance enhancement to me....had issues with EGR getting stuck from time to time before install) since I installed it. It will take a bit longer for engine to get to operating temp. but if you drive mostly 5 mile+ trips, it shouldn't be a problem.

shertex · #7 09-05-2020, 01:34 PM

Yeah, I've thought about that EGR emulator. Apparently 06 has few problems than 05 in that regard. I worry more about the swirl flaps...because of the labor involved. But it may be that they won't cause problems for a LONG time.