Test for blocked exhaust - TD5

[bsperka]

What is the best way to test for a blocked exhaust on a diesel? Disconnect the exhaust after the turbo, or do a temperature test (before after the cat or muffler), or other?

[Eevo]

go for a drive down the street, if it feels like its lacking power then it's normal.

[schuy1]

what makes you think it is blocked?

[bsperka]

what makes you think it is blocked?

1. I was looking for an easy way to check this on a diesel, as you can't hook up a vacuum guage, like on a petrol.

2. Also, looking for reasons why the turbo doesn't spool up on another forum member's car.

The obvious has been checked. At 2500 to 3000 up a hill and pedal all the way down, the boost slowly builds up. A long enough hill will most probably get it to 0.8 bar of boost, whereas in my TD5 it will quickly go to 0.8 to 1 bar at a small throttle setting.
Std map on the ecu, turbo checked, maf checked, map cleaned, waste gate actuator ok, throttle inputs ok etc. May be boost controller, but power is way down and no throttle response, no turbo lag, just like no turbo for a long time...

[bsperka]

go for a drive down the street, if it feels like its lacking power then it's normal.

I don't understand what you are saying...

[Alex 110]

I don't understand what you are saying...

He's just poking fun at the diesels - poor guy, wedded to a V8 -we should pity him:wasntme:

[schuy1]

I think Eevo is trying to say TD5's lack power! obviously an envious v8 driver! :D :D
Anyway back to your question. Does it rev freely in neutral no load? Turbo hoses?
has it suddenly died in the bum or is that not known? Air filter clean and intakes clear?

The exhausts on TD5s are pretty free with few places to block. The silencer is able to be unbolted from the rear pipe, if its original, Aside from that yes unbolt from the turbo and try. It could all so be the MAF? Lots of things other than a blocked exhaust could be causing it to do those things.

Cheers Scott

[Rok_Dr]

Lack of air or lack of fuel....

The Intercooler hoses are known to collapse internally which will strangle the performance.

On petrol engines I've also seen the same symptoms when the fuel filter is blocked.

[OffTrack]

Broken record here but I'll say it again: "record fuelling inputs to file while doing a test drive and post up the CSV file."

The ability to record inputs is the main feature that makes the Nanocom better for diagnostics than the Hawkeye. You should use it.

[bsperka]

Broken record here but I'll say it again: "record fuelling inputs to file while doing a test drive and post up the CSV file."

The ability to record inputs is the main feature that makes the Nanocom better for diagnostics than the Hawkeye. You should use it.

Mate, for a start what is a record? :angel: But seriously, this is the first time that I've seen that stated on AULRO. I'll see if we can do that, after removing some other potential causes. This is the first time that I've used the nanocom to fault find, rather than clear faults, so I'm on a learning curve.

[bsperka]

I think Eevo is trying to say TD5's lack power! obviously an envious v8 driver! :D :D
Anyway back to your question. Does it rev freely in neutral no load? Turbo hoses?
has it suddenly died in the bum or is that not known? Air filter clean and intakes clear?

The exhausts on TD5s are pretty free with few places to block. The silencer is able to be unbolted from the rear pipe, if its original, Aside from that yes unbolt from the turbo and try. It could all so be the MAF? Lots of things other than a blocked exhaust could be causing it to do those things.

Cheers Scott

Whilst the fault may not be a blocked exhaust, I'm still looking for a simple way to check for a blocked exhaust on a diesel, from a knowledge pov. Undoing the exhaust at the turbot is one way, but are there other methods.

For the fault, which in some ways is incidental to this post, it doesn't seem to rev as freely in neutral as mine, although mine has a remap. History of it is unknown as to how long the fault has been there (recent acquisition). Still need to check the other areas (intake). The only place I was thinking of a restriction is with the Cat, as its a D2a.

The MAF is giving slightly low readings. A changeover to mine, which is ok, didn't make a lot of diffference.

[bsperka]

what makes you think it is blocked?

See point 1. I'm trying to figure out a simple way to test for blockages.

The turbo takes forever to spool up, so if there is back pressure, this may stop it from doing it quickly. Obviously, it is one of many possibilities, with a low probability. Fuel economy seems to be good, it isn't blowing black smoke, so not being over fueled.

[bsperka]

He's just poking fun at the diesels - poor guy, wedded to a V8 -we should pity him:wasntme:

Oh, The poor guy hasn't seen the light yet.... although driving a diesel isn't the same as a petrol v8, I don't miss the guzzling fuel economy, higher rego, higher maintenance, shorter drives between refills.

Now for a real insult - so he's just like a Landcruiser owner critizing a Land Rover. :angel:

[Eevo]

Now for a real insult - so he's just like a Landcruiser owner critizing a Land Rover. :angel:

lol, i hope that isnt the best you can come up with. :)

[Rok_Dr]

Hi bsperka

To clarify what Offtrack says, if you plug the nanocom in and go to the instrument panel, you can record a log of the data that is displayed on the screen as you are driving. This can be captured on an SD card in a CSV format file which can be viewed in excel or other software package. It will really help diagnose the problem. Personally the log function and looking at the data has saved me a lot of time, frustration and $ in solving a couple of issues I've had, supported by the valuable advice of the members of this forum.

To capture the data, you first need to have an SD card inserted into the Nanocom. Then plug the nancom in, power it up and go to the instrument screen. At the bottom of the instrument read out screen towards the right side is a blue disk icon. Tap that and it goes to a file screen. Type in a file name hit ok and ok again and logging starts. Go for a drive and when finished tap the same icon again to stop logging and the nanocom will give an alert that the logging has stopped. Power the nanocom off, remove the SD card, plug it into your computer and open the file in excel, to look at the recorded data. If you can't make head nor tail of it, post the file here and the experts will be able give some comments.

There is a bit of a learning curve with the nanocom, but once you have used it a few times it all becomes easy.

Cheers

Steve

[OffTrack]

Mate, for a start what is a record? :angel: But seriously, this is the first time that I've seen that stated on AULRO. I'll see if we can do that, after removing some other potential causes. This is the first time that I've used the nanocom to fault find, rather than clear faults, so I'm on a learning curve.

Still a lot of new records released even in 2013: New Releases - Vinyl (http://www.insound.com/new-releases/vinyl) , but I digress.

It's often discussed in the electronic diagnostics forum which is where you'll find several years worth of posts about using tools like the Nanocom.

Let me google that for you (http://lmgtfy.com/?q=site%3Aaulro.com+record+inputs)

Most of the Td5 troubleshooting information is in that forum, so unless you been looking you wouldn't have seen it.

I'd add to Steve's post that you can save information from any screen on the nanocom that has a disc icon. In settings screens you'll get a file with the settings of the module. This is handy for backing up injector codes, or BCU settings for example.

In any section of a module that displays realtime data clicking save will create a file which logs all of the data available, not just what is displayed on screen. When you are recording inputs you need to touch the disc icon a second time to finish the data capture. I've found this has to be done before turning the engine off, otherwise the Nanocom looses communication with the ECU and the data doesn't save. :angel:

There are a number of ways of visualising data. If you use the Td5 engine module to record the fuelling you can view the data with Graphic Viewer CSV which you can download here:
td5 map suite (http://luca72.xoom.it/td5mapsuiteweb/downloads.html)

I've been using a free app on OSX which I find a bit more versatile, but you can also import into Excel.

http://www.aulro.com/afvb/electronic-diagnostic-systems/165643-nanocom-data-visualisation-osx.html

Bottom line is that it's a very powerful way to examine the way engine systems are behaving.

cheers
Paul

[bsperka]

Broken record here but I'll say it again: "record fuelling inputs to file while doing a test drive and post up the CSV file."

The ability to record inputs is the main feature that makes the Nanocom better for diagnostics than the Hawkeye. You should use it.

OK, I'm being a PITA, but after your post yesterday, I looked through the diagnostics section today (all 17 pages), as well as doing a search using your username, as well as searches using the terms "fuelling inputs" and "fuel". I struggled to find anywhere that you have said it... there are some places where it can be inferred though. Just saying.

That being said, it's a good diagnostic approach that may assist in resolving some engine related problems. It would be worthwhile putting up a post that talks about this approach in some detail.

[OffTrack]

OK, I'm being a PITA, but after your post yesterday, I looked through the diagnostics section today (all 17 pages), as well as doing a search using your username, as well as searches using the terms "fuelling inputs" and "fuel". I struggled to find anywhere that you have said it... there are some places where it can be inferred though. Just saying.

That being said, it's a good diagnostic approach that may assist in resolving some engine related problems. It would be worthwhile putting up a post that talks about this approach in some detail.

My comment about broken record was in reference to the other thread jadan had started.

I suggested to jadan, who you are helping out, that recording fuelling inputs might be helpful:

http://www.aulro.com/afvb/discovery-2/169157-td5-auto-question-post1858754.html?highlight=record#post1858754

And I also suggested it in reply to a post you made in the same thread yesterday:

http://www.aulro.com/afvb/1865107-post29.html

Maybe you should spend some time reading the documentation that came with the Nanocom instead of trying to annoy me.

[bsperka]

I'm not trying to annoy you about this, but obviously I have. Sorry about that chief. And yes, I'm trying to help jadan, but this thread is somewhat incidental to that at this time, hence its not against that thread. As one of the possibilities, I was wondering if a blocked exhaust could make the engine behave like this. This lead me to wondering how to detect a clogged / blocked exhaust in a diesel. Googled how to detect this in a diesel. Not much help there, so I thought I would ask the forum how they do it.

So, the topic is about trying to detect a blocked exhaust. If grabbing how the engine is behaving will assist in detecting a blocked exhaust (or other engine issues), then I'm interested in finding out more / how. Hence the request on how to do this and use them in general. Someone pointed out that the postings where under engine diagnosis, so I checked there, before putting up the previous post.

[Ollie]

Hopefully I'll learn a little too!
Thanks Ollie

[bsperka]

Temperature readings from a good catalytic converter.

Temp of the exhaust pipe prior to the catalytic converter 70 degrees C.
Temp of the exhaust pipe after to the catalytic converter 100 to 105 degrees C.

To and from the shopping centre 6 km run each way (10 min between runs) , low speed (50 kph residential, avg would be 20 to 30 kph), so little load, little throttle.

Cat converter about 3 years / 30,000km old.

Measured with infrared sensor, about 5cm from pipe and about 5cm from each side of converter.