Monday, November 16, 2009

What does the Measured Value block group 000 values tell you?

When you look at the Measured Values/Basic Settings in Group 000 in VAG-COM for the AAT up to 2nd control unit version engine you will see a group of 10 values in a row.

I've also included normal values measured during three different engine modes

Engine Stopped: Self explaining (with ignition key on)
Engine Idle: Idle, Warm engine, temp. at least 80 degrees C
Full Throttle: Warm engine, temp at least 80 degrees C. TEST DRIVE Accelerate the vehicle in 3rd gear (engine code AEL: in 4th; with automatic transmission: in gear 2) at full throttle (without kickdown) from overrun while a second mechanic observes the rev counter. Start logging in VAG-COM at 3000 rpm, do not exeed 4400 rpm (engine governed but keep an eye on the rev counter).


(Starting with row 1 at the left side of the VAG-COM screen.)
  1. Engine Speed

    • Engine Stopped: 0
    • Engine Idle: 33-36 OK
    • Full Throttle: 140-190 (190 = 4400rpm, not to be exeeded)

  2. Commencement of injection

    • Engine Stopped: undefined
    • Engine Idle: 45-60 OK
    • Full Throttle: 190-210 (depending on engine speed)

  3. Accelerator pedal position (max 255)

    • Engine Stopped: Press pedal to see value rise
    • Engine Idle: 0 (not pressed)
    • Full Throttle: 255 (floored)
  4. Injection Quantity

    • Engine Stopped: 0
    • Engine Idle:5-25 OK
    • Full Throttle: 115-125 OK (80 = emergency injection quantity)

  5. Intake manifold pressure

    • Engine Stopped: 117 at approx 1000 mbar
    • Engine Idle: 117 at approx 1000 mbar
    • Full Throttle: 210-235 (1.72 - 1.92 bar) OK

  6. Ambient Pressure

    • Engine Stopped: 240 at approx 1000mbar
    • Engine Idle: 240 at approx 1000mbar
    • Full Throttle: Ignore

  7. Coolant Temperature

    • Engine Stopped: 195 at approx 20 degrees C
    • Engine Idle: 62 at approx 90 degrees C
    • Full Throttle: Ignore

  8. Intake Air Temperature

    • Engine Stopped: 195 at approx 20 degrees C
    • Engine Idle: 177 at approx 30 degrees C
    • Full Throttle: Ignore

  9. Fuel Temperature

    • Engine Stopped: 90 at approx 20 degrees C
    • Engine Idle: 175 at approx 55 degrees C
    • Full Throttle: Ignore

  10. Intake Air Quantity

    • Engine Stopped: Ignore
    • Engine Idle: 41-75 (if EGR is working normally, if higher briefly press acc. pedal)
    • Full Throttle: at least 190 OK (<190 check airflow meter)

Monday, November 2, 2009

Dynamically adjustment of dieselpump timing.

Welcome to this post about dynamically adjustment of the diesel-pump timing, I haven't found any good guides on how to do this anywhere.

The equipment you need is this:

- VAG-COM or similar diagnostic software to get the dynamic values.
- HEX key to loosen the inboard bolt on the diesel-pump. (cannot remember the size)
- 13 mm spanner for the three remaining bolts
- Torque Wrench


Check this webpage for instructions on how to use VAG-COM to get TDI timing information plotted on a graph.

The first you need to know is whether the pump is too advanced or to retarded, you will find this in VAG-COM. (If yellow dots on graph is above green line the pump is too advanced, and vice versa). See picture below

(here the timing is too advanced)

What direction to turn pump:
- Timing too advanced, turn pump in direction of engine rotation. (belt tension increasing)
- Timing too retarded, turn pump in opposite direction of engine rotation. (belt tension decreasing)

NOTE: When you loosen all the bolts on pump, the belt tensioner will pull the pump in retarded direction.

Now you should loosen all the 4 bolts holding the pump, start with the worst locations first. It can also be smart to make a marking with a pen to know where you started your adjustment).

When you have adjusted, tighten all the bolts properly and fire up the engine and the VAG-COM to the timing. Most likely you need to do this adjustment two or three times to get it right.

When you are finished torque the bolts to 25NM, at last you should loosen and re-torque all the injector pipes at the injection pump to 25NM.
This ensures that the pipes are not subject to stress and avoids the possibility of fatigue fracture.

Hope this helps.

More pictures to come...

Sunday, November 1, 2009

Solution on "Unable to sync baudrate" in VAG-COM.

This is my solution when trying to connect to the engine ECU (adress 01) with VAG-COM, i did get the "unable to sync baudrate" every time.

Please be aware that all options in VAG-COM options page is at default, the Baudrate then says 0 for automatic detection.
This did not work for me on my third party el chipo ebay obd2 cable.

My solution was to change the baudrate in VAG-COM options from 0 to 240

That's it!
This worked on my Audi 100 2.5TDI AAT.

Welcome.

Welcome to this Audi 100 2.5 TDI blog.

I will try to post blogs about this car, doing repairs and so on. I'm having trouble finding tips and tricks on the net so I'm gonna try to put online all the tips and trick I'm using.

Enjoy