New user how to test Diesel Injectors?

[AdrianH]

First off I tried the software with an older ELM device and it read the ELM (version 1.0) but would not connect to vehicle, now have one of the blue-tooth adaptors from Konnwei and seems to work fine, can connect to car and read and clear error code so brilliant.

I am already using a diesel service garage local to me, and he found an error code saying the MAF was out of spec, so I ordered one and just replaced it. No more MAF error codes, but got a fuel pressure rail error for a while, now this seems to have cleared. Should I reset all data so the unit relearns everything when parts get replaced like the MAF?

The service engineer has already said that one of the injectors is at the end of it's spec this from running something very similar to Forscan if not the same. A screen showed 4 bar lines that changed with engine revs in some sort of test mode, bars 2, 3 and 4 seemed to move from a low to high value and injector 1 or bar one staid down at the low end of the scale.

I have bought an injector and will be getting this fitted soon by the service engineer.

Now this is where I ask for help.

Is there a section within forscan where it exercises the injectors and displays values, with an explanation of what it is doing and expected results for good and bad injectors.

I have looked through the documentation as much as I understand it.
I would like to periodically monitor things on the car see if things are getting better or worse, try some injector cleaners and see if the make a difference, etc.

Looking forward to any information you can help with.

Adrian

[FORScan]

Is there a section within forscan where it exercises the injectors and displays values, with an explanation of what it is doing and expected results for good and bad injectors.

I have looked through the documentation as much as I understand it.
I would like to periodically monitor things on the car see if things are getting better or worse, try some injector cleaners and see if the make a difference, etc.

Looking forward to any information you can help with.

Dealership scanner has a special Power Balance test for Mondeo Mk3, that shows the results in a some kind of graphical form. FORScan has no such a test yet. However, you can easily do this test using FORScan Dashboard or Oscilloscope function.

How to:

1. Run & connect, go to Dashboard section
2. Double click on a dashboard or press Setup button, PIDS selection dialog will be opened. Select ICU module. Select PIDs CYL1_RATIO, CYL2_RATIO, CYL3_RATIO, CYL4_RATIO and click OK.
3. Run the engine, wait until engine speed is stabilized at idle.
4. Click Start button and monitor for some time.

How to interprete test results:

If a CYLx_RATIO value is greater than 1.465, it means this cylinder is ok. If the value is 1.465 or less, it means the cylinder has a problem either with compression or with fuel injector.

One important thing: although PID is named Cyl, it is in fact Injector order and not cylinder order. So:

CYL1_RATIO - Injector 1, Cylinder A
CYL4_RATIO - Injector 4, Cylinder B
CYL2_RATIO - Injector 2, Cylinder C
CYL3_RATIO - Injector 3, Cylinder D


Example:

FM3_powerbalance_test.png (53.98 KiB) Viewed 40514 times

On this engine injectors 2 and 4 are ok (cylinders B and C). Injector 3 (Cylinder D) has some problems and needs to be checked. Cylinder 1 is above red line, but in fact very close to it so it may be does make sense to check it too.

[AdrianH]

Thank you very much for your answer, I will try this when I get the chance later on in the day and try to post a screen shot

Adrian

[AdrianH]

OK I had a go at this and strange as it seems in the images I have uploaded but cyl 1 seems to be generally the lowest, but difficult to show this when taking a snapshot, a bit like I could do with an averaging score for each?
Anyway here we go!

dash1.jpeg (88.36 KiB) Viewed 40479 times

So to show what I mean here is the same as an osc

osc1.jpeg (229.39 KiB) Viewed 40479 times

One can see looking at the upper and lower values that 1 and 3 are generally lower then the rest, 1 being the lowest range.

I am commited to having one changed soon so will see how things improve! afterwards

For interest i found other things to take reading of all with fuel in them so here they are:-

dash2.jpeg (103.55 KiB) Viewed 40467 times

osc2.jpeg (242.17 KiB) Viewed 40479 times

I have no idea yet what all mean, is there an explanation of all the item codes and what they mean?

Adrian
my photo editing skills are bad so corrected the dash2.jpeg.


I have a question about keys so will generate another post.

[FORScan]

OK I had a go at this and strange as it seems in the images I have uploaded but cyl 1 seems to be generally the lowest, but difficult to show this when taking a snapshot, a bit like I could do with an averaging score for each?

Maximum or average values are not important, but minimum value is. So minimum value should not be lower than 1.465.You can find minimum value using, for example, a rule tool in forscan (just click on a point in graph and it will show you current value in this point).

[AdrianH]

Maximum or average values are not important, but minimum value is. So minimum value should not be lower than 1.465.You can find minimum value using, for example, a rule tool in forscan (just click on a point in graph and it will show you current value in this point).

OK I understand a bit better, will have another go today.

Adrian

[AdrianH]

OK I had a go again tonight after work and this time I did not start the osc recording untill after the engine was running, therefore started at a value greater then zero, 0.

osc3.JPG (254.53 KiB) Viewed 40449 times

This does show that number 1 injector is going below 1.465, infact going down to 1.290 Going off this.

Looking at it Cylinder 3 is not far behind, now by my thinking with the firing order of 1,3,4,2. This means replace the injector in cylinder 1 and look at replacing injector in cylinder 4?

Adrian

[FORScan]

It is generally correct except this:

This means replace the injector in cylinder 1 and look at replacing injector in cylinder 4?

No, you should not replace anything just based on result of computer diagnostic! Basic rule is that you should use this diagnostic results to suspect some component, but not make final decision just based on it. In your case, you need to check compression of the engine. If it is much lower in cylinders ##1 and 4 (than in ##2 and 3), then it is the reason of power loss in these cylinders. Otherwise (if compression is OK everywhere), you may check injectors in cylinders ##1 and 4.

Another thing is that the PID values are just a level of "noise" from the cylinders. PCM "hears" it using a knock sensor, we believe. Knock sensor is usually placed in the middle of engine. So it "hears" cylinders ##2 and #3 better than #1 and #4 ones. As a result, you see lower level of signal in the graph. In other words, it may be normal that cylinders ##1 and 4 have less value than ##2 and 3. We have data from another Mondeo Mk3 2005 (2.0 TDCI 115hp 195000 km) and they are quite similar to your ones (cylinders ##1 and 4 have smaller signal than ##2 and 3, and cylinder 1 is also below the red line).

Also we have checked how it works in IDS and it seems the logic is slightly different from the one we described above. Principle is right (so if you ran it in IDS you would see Cyl1 in red zone and rest in green), but calculation of the balance value is a bit different. Besides, some initial conditions should be checked before: engine temperature and speed etc.

Well... It seems we were wrong and in fact it is not easy for user to implement such a test in FORScan manually (too many nuances). So it looks like it is a good idea to implement such a test in FORScan.

[AdrianH]

A little bit more on the car, it pinks, knocks especially when cold, it had a problem with the EGR valve, now cleaned and working OK, but not blanked off.

I took the car to a garage for a full service, to their extent anyhow, filters, oils and a good look over, It was strongly suggested I took it to a diesel expert to sort as it would give dark smoke on occasions etc. It went to the diesel specialist and using something similar (as mentioned earlier) he said two things wanted replacing, MAF, out of limits and the injector in cylinder 1. Now I can accept it has not had a compression check and as said now committed to having an injector replaced, I have it in the glove box ready, what I am hoping is that I can understand how others have got to this stage, get the injector replaced (Monday coming) and see an improvement and also map the changes in Forscan, then I may feel happier doing more like possibly changing the next one myself. So I am happy to play and provide results for tests as suggested, there is no discolouration of the oil to suggest water in it. The car pulls like a train when warm and will do 70 absolutely no problems at all, things have improved since the MAF replacement, but again, was not sure if I should clear any previous learned settings.

The car is running better, be it because of the MAF or I am running a cleaner through the fuel system is anyone’s guess.

I get confused with all the TLA's or three letter acronyms and what they all stands for, is there a glossary anywhere?

Keep up the good work, if there does become any subscriptions or donation let me know, I will help where I can.

Adrian

[mondeomk3]

Hello, I have been having problems with the mondeo, I suspect injectors

the P0251 appear sometimes and the was making some black smoke and also smells bad from the exhaust(like bad combustion)

What I done was a clean with liqui moly diesel purge and did like this https://www.youtube.com/watch?v=iq_ZGh1KEec , then I programmed the injectors with forscan

Now its much better, but not perfect!I

I check the CYLx_RATIO after one 100km travel and seams good, but I dont know if we should do it in cold or warm motor

here is my results