Problem with 2009 906 633 313CDI with OM646 2 Stage Turbo Engine - Page 2 - Mercedes-Benz Forum
Reply
 
LinkBack Thread Tools Display Modes
post #11 of 19 (permalink) Old 01-18-2018, 12:15 PM
Outstanding Contributor
SDS Guru
 
Deplore's Avatar
 
Date registered: Apr 2014
Vehicle: 1998 MB E300TD, 1997 MB E320
Location: LA, CA
Posts: 3,155
Mentioned: 124 Post(s)
Quoted: 763 Post(s)
Here's the thing though, as accurate the SDS compression tester is, it only counts the revolutions, not the actual compression. So you could have compression loss on all four cylinders, but if the compression speed is the same across all cylinders, the SDS will give it all OK....despite the fact that all cylinders had less compression than specified.

Found that the hard way.
Dave2302 likes this.

--1998 MB E300TD 291k
--1997 MB E36 Frankenstein'd AMG 199k
--2011 Suzuki DL650 58k
--1997 MB E320 161k. SOLD...loved that stupid car.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

--1997 MB C36 AMG 273k -- stripped and junked
Deplore is online now  
Sponsored Links
Advertisement
 
post #12 of 19 (permalink) Old 01-19-2018, 01:00 AM Thread Starter
Moderator
 
Dave2302's Avatar
 
Date registered: Nov 2013
Vehicle: V220 Ambiente S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Location: NW Scotland Near Eilean Donan Castle
Posts: 5,193
Mentioned: 72 Post(s)
Quoted: 717 Post(s)
Lifetime Premium Member
(Thread Starter)
Hi,

Yes, thanks for that, on the one hand that was exactly what I was thinking, and exactly why I have ordered the Correct Adaptor for my Diesel Compression Tester Kit.

However, (on that other hand), the less Compression, the faster it will crank, therefore I'd like to believe the SDS test is programmed to be pretty accurate, after all, any of us with a good ear can tell if a cylinder is low on Compression, you can hear it when Cranking, and also an Engine with Compression losses on all Cylinders spins over like a top , but yes worth sticking a Gauge on it

I will try and find out exactly what MB say the Compression Pressures should be, if anyone knows the Spec perhaps they could advise.

I do think a Compression Test should be the next move, make sure I'm not flogging a dead horse here, "and all that jazz"

FWIW, I think I said before, but in case I didn't, Glow Relay and Glow Plug function all checks out fine on SDS, and I know CDI ECU monitors it as I have a Code for 2 Glow Plugs in my old CDI Minibus.

But, tbh, that old Bussie always starts first hit even with 12" Snow on the bonnet at -10c, just takes about 1-2 seconds more cranking than before the GP's quit

Keep them suggestions and observations coming guys,

Cheers Dave
Deplore likes this.

Last edited by Dave2302; 01-19-2018 at 01:06 AM.
Dave2302 is offline  
post #13 of 19 (permalink) Old 01-19-2018, 03:48 PM
BenzWorld Junior Member
 
Date registered: Apr 2012
Vehicle: 280GE LWB 1982 RHD
Location: NZ
Posts: 33
Mentioned: 1 Post(s)
Quoted: 4 Post(s)
Quote:
Originally Posted by Dave2302 View Post
Meanwhile, if anyone has any suggestions, observations, or just plain want's to say "you silly old fart, you have not thought of 'xyz' " please feel free to chime in, I'm all ears on this one
Cheers Dave
Dave,

I've not digested the details you face, but make an observation based on my own experience. I have a 2001 SLK230 that was lighting up the dashboard, throwing up all sorts of codes, dropping into limp mode and driving me nuts as I spent serious money and time replacing all sorts of things... only to discover that the soldering on the onboard diagnostic computer was getting old and cracked. In other words, it was not a mechanical problem that threatened life and limb, but a "safety" system designed to diagnose that was failing.

This is the ugly secret of later model used vehicles... that as Mercedes went from mechanical systems to electronic, they did not maintain the same level of permanent reliability. Thus, before you believe the codes, make sure the code-maker is not a false-code generator.

In my case, a $200 black box from the wrecking yard, and 15 minutes to replace made all the lights go out and the dangerous limp mode cease. All symptoms cured, and there was nothing wrong with any of the actual mechanics (brakes, ABS, transmission, etc.) that the codes were blaming.
Dave2302 likes this.
rhd280 is offline  
Sponsored Links
Advertisement
 
post #14 of 19 (permalink) Old 01-19-2018, 10:30 PM
Outstanding Contributor
SDS Guru
 
Deplore's Avatar
 
Date registered: Apr 2014
Vehicle: 1998 MB E300TD, 1997 MB E320
Location: LA, CA
Posts: 3,155
Mentioned: 124 Post(s)
Quoted: 763 Post(s)
Actually MB has improved a bunch since the w210/202/170 k40 relay fiasco. Shoddy soldering isn't a problem on newer Mercedes.
Dave2302 likes this.

--1998 MB E300TD 291k
--1997 MB E36 Frankenstein'd AMG 199k
--2011 Suzuki DL650 58k
--1997 MB E320 161k. SOLD...loved that stupid car.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

--1997 MB C36 AMG 273k -- stripped and junked
Deplore is online now  
post #15 of 19 (permalink) Old 01-20-2018, 02:26 AM Thread Starter
Moderator
 
Dave2302's Avatar
 
Date registered: Nov 2013
Vehicle: V220 Ambiente S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Location: NW Scotland Near Eilean Donan Castle
Posts: 5,193
Mentioned: 72 Post(s)
Quoted: 717 Post(s)
Lifetime Premium Member
(Thread Starter)
Hi,

Thank you both for the posts.

I would be looking seriously at an Engine ECU Problem, if this were 1999 to 2002 era, but it is a 2009 model year, and I have spoke to both Mercedes and BBA Reman, who say there is not a known ECU issue that would flag these Codes, also it is too consistent and irrespective of Humidity, Temperature, Vibration etc etc

Also, I recently had a newer 2 Stage Turbo OM651 in with problems, and I had Glow Controller, MAF, MAP, IAT, Boost Solenoids and a whole ton of other stuff disconnected and removed to get at the Faulty Solenoids, and whilst waiting for parts from MB, I needed to get it out of the Workshop.

It still fired up straight away, and drove out of the workshop to be parked fine.

I have found with all CDI's I've worked on, (a fair few lol), you can disconnect a helluva lot and they still start OK

Anyways, keep 'em coming, the more I'm thinking about this the more it don't make sense, and there is still certainly at least 2 faults .com

We have given thought to buying a "Salvage" crashed Sprinter which is still running OK and just swapping parts, then sell the rest on again
However, parking for large wrecks is rapidly becoming an issue, and no one up here takes scrap away atm, prices are right low these days I have a scrap Vito and a scrap Fiat Scudo Van taking up valuable space right now, plus the faulty Sprinter

I don't need a Workshop, I need a heated and insulated Aircraft Hanger with a 2 Acre Parking lot

Cheers Dave

Last edited by Dave2302; 01-20-2018 at 02:32 AM.
Dave2302 is offline  
post #16 of 19 (permalink) Old 04-15-2018, 04:09 AM Thread Starter
Moderator
 
Dave2302's Avatar
 
Date registered: Nov 2013
Vehicle: V220 Ambiente S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Location: NW Scotland Near Eilean Donan Castle
Posts: 5,193
Mentioned: 72 Post(s)
Quoted: 717 Post(s)
Lifetime Premium Member
(Thread Starter)
Hi Guys,
@rhd280 , @Kajtek1

OK, OK,

Hands up who remembers THIS Sprinter with the OM646 Dual Stage Turbo Engine that had me head scratching ???????

To Recap, it came to me last year, with "chokka blocked" DPF and a bunch of Fault Codes. Very Poor Starting, needed a ton of Cranking.

Back then I did every SDS Test possible and fixed all but one Code, but still the beast was very very hard to start !!
But when it finally started, after fixing all the other Codes and getting DPF to Re Gen it ran lovely, pulled OK but kept flagging "Air Flow Offset Drift" Code.

It always sounded like it was Cranking OK, no ups and downs on Cranking RPM, and passed SDS Compression Test which monitors Cranking RPM and Graphs it ............. IIRC it did show #2 Cyl was slightly borderline, but bearing in mind when I blew a big hole in a piston on another CDI, and that still started up quick, I wasn't convinced it was a Compression issue, nor was anyone else !! Everyone was saying Fuelling issue.
It also idles sweetly, smoothly and sounds great when it is running !!

Well, since the last post on it, it was left Parked Up taking up space, the Owner understood I couldn't physically get it into the Workshop due to my Doors only being 8ft high, so we decided to resume works once the Winter Weather broke.

Got back at it yesterday and I now know exactly what is wrong with it

I had meanwhile done a ton of research and actually got some real meaningful figures for various tests on the Fuel System, also I bought the MB Glow Plug adaptor for my Diesel Compression Tester Kit, so I could actually make sure we weren't flogging a "dead horse".

So, yesterday I repeated the Injector Spill, Fuel Rail Regulator, and Pumps Tests, all checked out fine, well within the "Leak Off CC's Specs" and "Pressure PSI Figures" I was given.

As I had kinda expected, so glad we didn't go chucking expensive bits like Pump, Fuel Rail etc at it !!

OK, so lets look at these Compressions then with a Decent Pressure Gauge.

The bear of this is you gotta get them Glow Plugs out without snapping, so got it really hot, and got 'em out

Here we go ............

Cyl #4 = 650psi

Cyl #3 = 650psi

Cyl #2 = 150psi

Cyl #1 = 150psi

Baaaaaaaadumph !!

Yep, the aforementioned "Dead Horse" has been well and truly flogged

Ok I don't get how it runs so sweet once it's started, but yeah, losing 2 of it's 4 "Suck Squeeze Bangs" while Cranking will cause it to be a bitch to start, and also, if, as I suspect now, it is a Head Gasket / Block Face / Head Face issue, then the fact that the 2 Cylinders are probably pumping across into one another while the other Cylinders Valves are open, yeah, that will give the Airflow Offset Drift Code !!

Kaaaaaaaaaching !!

Plan of action now...................

I don't wanna do it !!

If I had more space I would love to but it won't go in my Workshop, once I strip the Head off it it is immobilised, I can't push it outta the way, so I'm seeing the owner Monday to discuss the way forward.

I'm going to recommend he takes it to a big Engine / Head Re Mfr in Inverness, will speak with them first, first thing Monday !!

I suspect, as this is a long standing problem, and he literally drove it for ages like this, the Head will be Burnt and possibly the Block, across the Gasket Face between the Cylinders, so will require the Block Deck Skimming, maybe a new Head etc etc ...........................

Nope, I haven't the room to store it and do the job ................... Farm it out

But, at least it didn't beat me I sussed out what is wrong wi' it

So, anyway, DO NOT rely on an SDS Compression Test !!

But, like I said, and I'm sure some of you know, if an Engine is down on Compression, normally you can here the RPM hop up and down as it is cranking, normally it will idle rough, but this beasty didn't do that ...............

That I cannot explain

IIRC waaaaay back, it also passed the running Cylinder Balance Test on SDS too

Cheers for now,

Dave
Kajtek1, pinkster and Deplore like this.
Dave2302 is offline  
post #17 of 19 (permalink) Old 04-15-2018, 12:16 PM
BenzWorld Elite
 
Kajtek1's Avatar
 
Date registered: Dec 2005
Vehicle: E320/E250 Bluetec Ford F350 6.7l
Location: V E G A S
Posts: 35,396
Mentioned: 30 Post(s)
Quoted: 1978 Post(s)
Thanks for getting back with final report.
Kind of suck that simulated test proved worthless.
I did not expect it to be precise, but was having hopes it will give you rough data.
So you don't want to pull the engine and carry it to your shop for rebuild?
I just restarted 624 engine that I bought "rebuild" from UK.
the "" are becouse they did not put all the bolts back in and I had additional problems with it.
Now how did you regenerate DPF? I have problem with it on 651 engine and spending quite good money on Liquy Molly purge did not help.
Dave2302 likes this.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Kajtek1 is online now  
post #18 of 19 (permalink) Old 04-16-2018, 12:01 AM Thread Starter
Moderator
 
Dave2302's Avatar
 
Date registered: Nov 2013
Vehicle: V220 Ambiente S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Location: NW Scotland Near Eilean Donan Castle
Posts: 5,193
Mentioned: 72 Post(s)
Quoted: 717 Post(s)
Lifetime Premium Member
(Thread Starter)
Hi,

I will always report an outcome once I know it
Nothing worse that a post without outcome, even if it is simply " I bought another car and gave up on this one"

Re Gen ..........

There are a lot of fault codes that can be stored in Engine ECU which will not allow the DPF to Self Regen whilst Driving, things such as Air Flow Codes, EGR Codes, Lambda Codes, EGT Sensor Codes they are the ones I know will stop Re Gen, I expect there are others

This is why it is so important that owners do not keep driving with EML on, just because "it's driving OK right now" ...............

That is exactly what this guy did, and gradually it got worse and worse.

After I replaced all the Coked up and FUBAR Sensors all I was left with was this Airflow Drift Code and a blocked DPF.

I cleared the Airflow Code, got it up to temperature and did the "DPF Regen" function in SDS, which cleared out the DPF a treat.

After all that, it was still a bugger to Start, but once started the Van drove much better, pulls OK, Idles real sweet but just kept flagging that Airflow Drift Code, and would then go into limp mode, at this point I could then see DPF Soot Level starts to rise

The fact that it drove and idled so well plus passed SDS Compression Test is why I wasn't convinced it was a Compression Issue, but there we go

It definitely makes sense now I've seen the Gauge Readings, and btw I tested them again yesterday with same result, before re fitting Glow Plugs.

The figures above were HOT Engine, yesterday was COLD Engine, and they were all a bit lower !!

It may well have been "Cooked" at some point, it certainly had this starting problem when he bought the Van, had been to various Garages who had changed this and that, including all 4 Injectors, never got cured

Then I got it

Cheers Dave

Last edited by Dave2302; 04-16-2018 at 12:03 AM.
Dave2302 is offline  
post #19 of 19 (permalink) Old 06-17-2018, 11:10 AM Thread Starter
Moderator
 
Dave2302's Avatar
 
Date registered: Nov 2013
Vehicle: V220 Ambiente S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Location: NW Scotland Near Eilean Donan Castle
Posts: 5,193
Mentioned: 72 Post(s)
Quoted: 717 Post(s)
Lifetime Premium Member
(Thread Starter)
Hi,

Just a final final update on this

A few weeks back I ended up doing the job, managed to get some space in a well lit and dry Barn near me, so I loaded up my van with a bunch of tools, engine crane etc and set about it

Guy decided to spend some real coin ......................

I fitted a Rebuilt "Ivor Searl" Engine, all new Filters plus new Glow Plugs, Injector Seals, New Injector Bolts, New Water Pump, New T/Stat and Housing assy, New DMF and New Clutch, and all new MB O Rings and Seals in the Dual Stage Turbo and Intake Butterfly etc etc.

Vehicle also had a new Lower Swivel and 2 Rear Brake Pipes for it's MOT Test.

Owner happy as a pig in sh!te now albeit with a much lighter wallet

The van pulls like a train, starts first turn, and is driving as it should

Cheers Dave
Deplore likes this.

Last edited by Dave2302; 06-17-2018 at 11:15 AM.
Dave2302 is offline  
Sponsored Links
Advertisement
 
Reply

  Mercedes-Benz Forum > Mercedes-Benz Vans/Trucks/SUV/Others > W901-906 Sprinter

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 

Title goes here

close
video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome