Injector readings
 

A mate put the fear of failing injectors in my head the other day and mentioned about the message blocks within the engine module.

Module 01, Message blocks 72 to 77 (I think).
Apparently the numbers for these blocks should be within -10 and +10.

I've looked on Google but having issues finding the correct procedure/numbers for making sure my injectors are not failing.

Can anyone confirm this procedure and numbers?

Here are text files I pasted into Notes, so sorry I don't have the original sources, but it was Official Audi documentation.....



White smoke from the exhaust system and juddering when the engine runs at idle speed for some time - V6 TDI 2.7l / 3.0l TDI.

Technical background

Mechanical wear of the needle attachment of the injector leads to an increased fuel injection into the combustion chamber. The fuel is not completely burnt, which causes white smoke (unburnt fuel) or juddering when the engine runs at idle speed for some time.

This complaint occurs only on vehicles with more than 50,000 km.

Production change

Modified injectors from:

8E47A040360

4F37N026750

4EX7N004204

4L*7D049162

Measure

Try to reproduce the customer complaint so that it can be clearly assigned to this TPI. The following repair must only be carried out, if all the criteria (model/type, chassis number, engine/gearbox code, PR number(s), software version, code etc. ) match exactly. Otherwise this solution won't work and repeat repairs may be necessary. In such a case, we may reject the warranty claim and redebit the parts.

Read the measured value blocks 72 - 77.

3 values per measured value block appear there (for 300 bar, 600 bar, 1000 bar).

Should the values be higher than minus -45 ms (example - 60ms) or

on digit 2 be

higher than minus -15 ms (e.g. 20ms),

the needle attachment is worn and the injector is incorrect. To avoid repeat repairs, replace all 6 injectors.

>>>> Observe the algebraic sign (minus) in measured value block 72-77 !!!!! <<<<<

Warranty accounting instructions

Service number/damage code/manufacturer: 2340/010

************************************************** ************************************************** ****************************

After an overnight stationary period drive the vehicle with cold engine between 1200 - 1600 rpm till the complaint occurs. Constantly read the measured value block 13 and 14 for the smooth running control in the engine control unit. The values of one or several cylinders should noticeably move to positive.


modified injectors A8: with 3.0l, 4.2l TDI from: WAUZZZ4E*7N016685

Replace the injector with the highest deviation and all injectors produced between 1.3.2006 and 30.4.2006.

Example of production date: 060304 stands for 4.3.2006

vcds go to address 01 measured values below

013 Smooth running control
1)Cyl. 1 Injection quantity variation [mg/stroke]
2)Cyl. 2 Injection quantity variation [mg/stroke]
3)Cyl. 3 Injection quantity variation [mg/stroke]
4) Vacant
Permissible values at idle: +- 2,99 mg/stroke
A If the permissible tolerance is exceeded
first check injector IQA-IVA adaption values

014 Smooth running control
1)Cyl. 4 Injection quantity variation [mg/stroke]
2)Cyl. 5 Injection quantity variation [mg/stroke]
3)Cyl. 6 Injection quantity variation [mg/stroke]
4) Vacant
Permissible values at idle: +- 2,99 mg/stroke
A If the permissible tolerance is exceeded
first check injector IQA-IVA adaption values

Thanks for that.

Attached is my readings.

They look ok, I think.

Not sure if we are in the correct blocks there Scott , think we should be reading the corrections ( injector trim ) in mg / str like in Snaps posting .

Just another point I see on range rovers with the 2.7 or 3l diesel that have twin egrs , if one egr bleeds across a little it affects all the cylinders on that bank so you could think injectors are near to the ends of the operating window but really it's egr gases affecting them .
I just blank egrs off and if injector corrections' clean up ' somewhat you know your on the right track .

I'll take a look at blocks 13 and 14 later.

There is only 1 EGR on our V6......I think.
If we block it the engine will error due to not enough air flow through the EGR.
Nice idea though.

Yes Scott, the Range Rover flags insufficient egr flow codes also but if the trims come more into line it proves there was some leakage through the valve .With just the one egr it wouldn't be bank specific

Are they piezo on the v6 , what mileage are you up to

No idea.

I'm currently on 174k with full service history.

Popped out to the car this morning to do a cold start as I just had all glow plugs replaced.
While I was at it I thought I would check blocks 13 and 14.
attached is my reading.

The post that Snap posted up says:
Permissible values at idle: +- 2,99 mg/stroke
A If the permissible tolerance is exceeded
first check injector IQA-IVA adaption values

I assume that means that they should be withn the range +2,99 and -2,99?

All look good them Scott hardly any deviation from the 0.0 base , does the car start well , run smooth with no white smoke , if yes I don't think there is any cause for concern .

Hi Lee,

The rear windows are tinted. I can see bugger all from the back, so don't know.
I've not seen any smoke from the side mirrors.

It starts fine now I had the glow plugs replaced.

That's good news, I'll ignore the injectors now and move on to something else.