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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #1
My sister has been driving the truck, and lately she said there is a once in a while shutter when starting up.

Today while she was driving on the freeway she got a shutter and it died. I arrived and the car would crank for a bit, then start up. After about 20-30 seconds or so it would shutter a lot and die- like it was starving for fuel or something. If I started the car the instant I pressed the throttle it would die as well. As some of you know after the car starts, the RPMs are higher, after about 20-30 seconds the RPM's drop, that is when it would shutter and die- or when pressing the throttle at all.

The shutter somewhat reminded me of when my plug wires were going out (replaced 3 or so years ago). I think this is also when the spark plugs were last replaced.

Any ways, the truck has 230K miles on it and I was hoping to get some diagnosis help. I am very much a DIY kinda person but don't want to throw cash at it. I had to have it towed to my house. I plan to plug in my Audi VAG COM cable- which can pull OBD-II codes- although I have never done it, we will see if anything is said there.

Any help would be greatly appreciated!!!
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #2
I just went outside to start the car, its been about 2 hours since I had it towed home.
Car took a bit to start, it continued to crank until I started- about 15 seconds.
Once it started it sat around 900-1000 RPM's. Then after its typical delay of about 20 seconds the RPM's dropped to around 500 RPMs (this is was normally happens with the car).

Once it hit 500 RPMs it started shaking and stuttering for 2 or so seconds, and the car automatically rev'ed up the engine to around 2000 RPM's. It sat there for 3 seconds and dropped back down to 900-1000 RPM's. After 20 seconds it dropped to 500 RPM's and started shaking, this happened over and over. It never actually died this time, but keep running though the same routine.

No matter where the RPM's were, if I touched the throttle it would drop down in RPM's and start shaking and stuttering and would almost die. I would have to let off the throttle immediately if I didn't want it to die right there.

I turned it off after it had done it 3-4 times.

Hope that helps! Thanks again!
 

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2002 ML55 AMG, 2005 Chrysler Crossfire Coupe Limited, 1999 C280
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4,714 Posts
Obtain and post the OBDII codes already! LOL

I'm no expert but my money is on your MAF.
 

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Dallas, Texas
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7,743 Posts
Those are symptoms of large vacuum leak, stuck open EGR valve, unresponsive MAF or low fuel pressure.

Using VAG retrieve codes, freeze frame data, STFT and LTFT for both banks.
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #5
Those are symptoms of large vacuum leak, stuck open EGR valve, unresponsive MAF or low fuel pressure.

Using VAG retrieve codes, freeze frame data, STFT and LTFT for both banks.
I am planning to go and buy a OBD-II scanner from Harbor Freight:
OBD II/EOBD Multilingual Code Scanner

I tried with my VAG-COM cable for my Audi, it said it pulled codes, but I didn't see anything. I would rather get a genaric unit to make sure I am doing it right. I know I can do freeze data on that unit listed. Not sure how to do the STFT and LFTF for both banks though.
 

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Dallas, Texas
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OBDII in VAG is as generic as it gets. What version of software and hardware are you using?

I don't see live data section in Harbor Freight tool.
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #7
I just upgraded the latest Ross Tech software last night... hardware is a Ross Tech HEX-COM (serial). I guess I am not just that familiar with the Ross Tech software for OBDII fuctions as I am with VAG functions.
 

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99 White ML320, 13 Audi S5,84 300ZX Turbo, 03 Audi A4, 03 Audi TT, 65 Ford Galaxie Conv
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474 Posts
Have no proof of this, but here is what I would think is going on. By the way, I have the Ross-Tech VAGCOM as well and would never have thought of doing this, so good on you for trying.

I would assume that the Ross-Tech tool "pairs" the generic OBD codes with the more specific Audi codes and then adds these to the Audi only codes. In the process of all this, the software that creates the report gets "confused" by all the Benz only data and gives you nothing. As far as generic readers, the car manufactureres are required by EPA to interface with generic readers, so these are not a problem unless it is a CAN versus the other format, what ever that one is. Again, I have no proof of this, but seems reasonable. I would call Ross-Tech and see if they will answer the question and then repost.
 

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I just upgraded the latest Ross Tech software last night... hardware is a Ross Tech HEX-COM (serial). I guess I am not just that familiar with the Ross Tech software for OBDII fuctions as I am with VAG functions.
Here are few screen shots using OBDII in VAG.
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #11
So what I need

So what I need is the information from the following Modes:
Mode 1- Short Term Time Bank 1+2 and Long Term
Mode 1-01- All messages
Mode 3- All messages
Mode 7- All messages

Do I need to view anything in Mode 2 (Freeze Frame)?

I am assuming I should be pulling this information while the car is running, and hopefully (not really) stuttering.

Anything else I need to pull?
 

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1999 E55, 2001 E320, 1990 560 SEC, 2004 ML350, 2001 ML55, 1995 S500, 1998 SL500, 2010 E550 Sport zoo
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7,035 Posts
I bet on unresponsive MAF, but we will see.
 

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Dallas, Texas
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So what I need is the information from the following Modes:
Mode 1- Short Term Time Bank 1+2 and Long Term
Mode 1-01- All messages
Mode 3- All messages
Mode 7- All messages

Do I need to view anything in Mode 2 (Freeze Frame)?

I am assuming I should be pulling this information while the car is running, and hopefully (not really) stuttering.

Anything else I need to pull?
You can read mode 3,7,2 with just key in position 2.

When saving give file some meaningful name. Save data from each mode. Program will append to same file.
 

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99 White ML320, 13 Audi S5,84 300ZX Turbo, 03 Audi A4, 03 Audi TT, 65 Ford Galaxie Conv
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474 Posts
Witek once again shows his brilliance :bowdown::bowdown::bowdown: and how dumb us amatuers are...

I am off to try this soon.
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #15
You can read mode 3,7,2 with just key in position 2.

When saving give file some meaningful name. Save data from each mode. Program will append to same file.
You're the man! I will post the info as soon as I get home and try it!
 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #16
Well here is what i have come up with so far...
First I have no codes recorded at all, both on Current DTC's and Pending DTC's... here is the combined output:
Mode 03: Emission related fault codes

Address 01: No fault code found.

Thursday,16,December,2010,18:46:10:01595
VCDS Version: Release 10.6.3
Data version: 20101206


Mode 07: Pending emission related fault codes

No fault code found.
Thursday,16,December,2010,18:46:42:01595
VCDS Version: Release 10.6.3
Data version: 20101206


No Freeze Frame Data available.
Thursday,16,December,2010,19:53:18:01595
VCDS Version: Release 10.6.3
Data version: 20101206



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Mode 01 - PID 01 : Readiness -- Address 01

Number of DTCs stored: 0 -- MIL Status: MIL ON
Misfire monitoring: Passed
Fuel System: Passed
Comprehensive Components: Passed
Catalyst monitoring: Failed or Incomplete
Heated catalyst monitoring: Not installed.
Evaporative system monitoring: Failed or Incomplete
Secondary air system monitoring: Failed or Incomplete
A/C system refrigerant monitoring: Not installed.
Oxygen sensor monitoring: Failed or Incomplete
Oxygen sensor heater monitoring: Failed or Incomplete
Exhaust Gas Recirculation: Failed or Incomplete

I attached an image of the read out of the Short Term Trip and Long Term Trim. The recording stopped when the car died. Long term trim stays steady at 34.4 but I get nothing from short term trim. Is there something else I should log?

 

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2000 ML320, 2000 Audi TT Quattro, 1996 Acura NSX-T
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234 Posts
Discussion Starter #17
I also took a video of exactly what was going on... Here is the breakdown...
Note I do not touch the gas until 1:35 into the video

Start Car at: 10 seconds
Car drops in RPMs: 35 seconds
Car Shutters hard until: 34-37 seconds
Car self throttles: 38 seconds
Car Shutters hard again: 1:07
Car drops in RPM's again: 1:22
Car recovers: 1:23
Car drops down again: 1:26
Car almost dies: 1:28
Car shoots up in RPM's again: 1:30
I press gas peddle slightly: 1:35
Won't rev over 1500RPMs: 1:38
Drops down, and I give it gas again at: 1:46
Car dies after 3rd time I touch the gas: 1:52
Restart car at: 1:58
Cycle continues
 

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Dallas, Texas
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Fact that all emission monitors are in incomplete state means that battery died, battery was disconnected, codes ware erased. First three lines are always complete unless something is flat out disconnected.

LTFT (Long Term Fuel Trim) stuck at 34.4% is way off the scale. Normal is up to 10%. From 10 to 25% car starts running funny with poor throttle response and poor fuel mileage. At >25% CEL comes on.
 

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02 ML320 06 ML500
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17,104 Posts
Regardless of what your problem is, "E lining" the gas tank is not a good practice. If not already partially clogged, the fuel filter could be part of your problem.

Also the Evaporative Monitor will never run complete unless there is at least ¼, but no more than ¾ fuel in the tank.
 
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