cdi turbo lag??? - Mercedes-Benz Forum
 
LinkBack Thread Tools Display Modes
#1 (permalink) Old 06-20-2008, 07:49 PM
BenzWorld Member
 
Date registered: Mar 2007
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
cdi turbo lag???

On at least 3 occasions, I was coasting on the highway and I floored the accelerator, the car didn't bulge-- a good 3 seconds later it gradually gained speed. Then, some half an hour later it picked up properly. Any idea what happened???
Famercedes is offline  
Sponsored Links
Advertisement
 
#2 (permalink) Old 06-21-2008, 04:51 AM
BenzWorld Elite
 
drivbiwire's Avatar
 
Date registered: Mar 2006
Vehicle: 2006 E320 CDI, 2009 ML320 Bluetec, 2009 GL320 Bluetec
Location: Boise ID
Posts: 1,476
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
What air filter are you using?

Your MAF sensor could be contaminated, this will not result in an engine code.

DB
drivbiwire is offline  
#3 (permalink) Old 06-24-2008, 06:21 PM
BenzWorld Member
 
Date registered: Mar 2007
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
I'm using Mann filter. And yes, I have no codes showing up whatsoever...
Famercedes is offline  
#4 (permalink) Old 06-24-2008, 09:37 PM
BenzWorld Elite
 
Kajtek1's Avatar
 
Date registered: Dec 2005
Vehicle: W210 E300DT x2/w211wagon4M / Ford SD. Seeking diesel pushmower
Location: CA Bay Area
Posts: 27,258
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 71 Post(s)
One of the tests for turbo is listening how long it turn after you turn the engine off.
You might need to take the air hose off to see the impeller.
Don't know specific time for MB, but generally it should be at least 20 seconds.
Kajtek1 is offline  
#5 (permalink) Old 06-25-2008, 02:22 PM
BenzWorld Elite
 
drivbiwire's Avatar
 
Date registered: Mar 2006
Vehicle: 2006 E320 CDI, 2009 ML320 Bluetec, 2009 GL320 Bluetec
Location: Boise ID
Posts: 1,476
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Kajtek1 View Post
One of the tests for turbo is listening how long it turn after you turn the engine off.
You might need to take the air hose off to see the impeller.
Don't know specific time for MB, but generally it should be at least 20 seconds.
Total bull$hit!

The VNT-23 accelerates from 10,000 rpm to 180,000 rpm in about .4 seconds. It goes from 180,000 rpm to 0 in about 4 seconds. Once the exhaust gas stops flowing, and the incoming air stops the turbo comes to a rapid stop due to flow stagnation.

The turbo is a lightweight high temperature alloy inconel turbine, cast aluminum low mass compressor spinning on an oil film .10mm thick on a brass bearing/sleeve. It simply lacks the mass to sustain motion for any period of time, this also aids in VERY rapid acceleration characteristices required in order to meet strict emissions.

The turbine on these cars is not much larger than a US quarter in diameter and the compressor the size of a half dollar.

FWIW, My CF-6's won't even spin for 20 seconds after shutdown and the shafts and blades weigh in excess of 3,000# (6,000# for the whole motor).

DB
drivbiwire is offline  
#6 (permalink) Old 06-25-2008, 08:08 PM
BenzWorld Member
 
Date registered: Mar 2007
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
DB,
I'm cruising on the highway, I step on the pedal- nothing happens and then about a full second later the car picks up... What could cause this lag? When I exited the highway, at a light, the car reminded me of my 1983 300 D, during take-off!!! Any suggestion is truly appreciated!
Famercedes is offline  
#7 (permalink) Old 06-25-2008, 10:54 PM
BenzWorld Elite
 
Kajtek1's Avatar
 
Date registered: Dec 2005
Vehicle: W210 E300DT x2/w211wagon4M / Ford SD. Seeking diesel pushmower
Location: CA Bay Area
Posts: 27,258
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 71 Post(s)
Quote:
Originally Posted by drivbiwire View Post
It goes from 180,000 rpm to 0 in about 4 seconds.
Do you actually know it, or guess it?
As I said, I didn't play with turbo on W210, but the bad one in W124 was spinning for several seconds with hand push.
The good one in my Ford runs about 28 seconds coming down from the idle.
You made me curious. I need to listen to the one in 300dt.
Kajtek1 is offline  
#8 (permalink) Old 06-26-2008, 10:28 AM
BenzWorld Member
 
HFMB's Avatar
 
Date registered: Feb 2006
Vehicle: 2006 E320 CDI
Location: Cleveland, OH
Posts: 237
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Famercedes View Post
On at least 3 occasions, I was coasting on the highway and I floored the accelerator, the car didn't bulge-- a good 3 seconds later it gradually gained speed. Then, some half an hour later it picked up properly. Any idea what happened???
How fast were you going? Are you sure it was not the transmission trying to figure out what gear to be in? I've had that happen, especially when transitioning from coasting to accelerating when going slowly or down an incline--the trans wants to stay in a high gear then finally realizes I want to move, then it shifts! I've always thought these MB transmissions are slow to compute...

Hugh
2006 E320 CDI
2001 C240
2003 Toyota Tacoma DoubleCab 4x4
HFMB is offline  
#9 (permalink) Old 06-26-2008, 07:16 PM
BenzWorld Elite
 
drivbiwire's Avatar
 
Date registered: Mar 2006
Vehicle: 2006 E320 CDI, 2009 ML320 Bluetec, 2009 GL320 Bluetec
Location: Boise ID
Posts: 1,476
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Kajtek1 View Post
Do you actually know it, or guess it?
Know it...

Quote:
As I said, I didn't play with turbo on W210, but the bad one in W124 was spinning for several seconds with hand push.
The good one in my Ford runs about 28 seconds coming down from the idle.
You made me curious. I need to listen to the one in 300dt.
The W210's turbo is decades behind the VNT series turbos. The W124 is the model T of turbos! Heavy, slow response, lower temperature alloy, lower efficiency compressor etc etc.

You also forget that the VNT has VGV technology that acts to increase backpressure and control the gasses acting directly on the turbine. VGV's permit EXTREMELY rapid response in terms of acceleration and deceleration.

DB
drivbiwire is offline  
#10 (permalink) Old 06-27-2008, 06:41 PM
BenzWorld Member
 
Date registered: Mar 2007
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
I was going at about 75 mph. I've experienced the trans hesitating going down an incline. Actually when I got off the highway, after a stop at the light, it hesitated then picked up gradually. An hour later, I start the car to go out and drove the car, everything was fine...???
Famercedes is offline  
Reply

  Mercedes-Benz Forum > Mercedes-Benz Sedan Forums > W211 E-Class


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Topic Author Forum Replies Last Post
More lag than a turbo???? jgorman13 W204 C-Class 37 02-27-2008 05:02 PM
CDI Turbo Problems Lotzacars W211 E-Class 14 03-07-2007 12:59 AM
Cdi Or Turbo Diesel TOMMYMCA79 W210 E-Class 0 08-27-2006 12:54 PM
Turbo lag MBeige W123 E,CE,D,CD,TD,TE Class 14 05-17-2005 10:00 PM
CDI turbo in a 123 3.0TD Rocha W123 E,CE,D,CD,TD,TE Class 0 12-02-2004 11:11 AM

Posting Rules  
You may not post new threads
You may not 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

 
For the best viewing experience please update your browser to Google Chrome