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D40 sluggish and burning excessive fuel
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Old 02-02-2018, 05:14 AM
Vomitbomb Vomitbomb is offline
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Default D40 sluggish and burning excessive fuel

Hi all,

It's a bit of a saga and I apologize for the long winded post. Figured it would be a good idea to throw in as much (hopefully) relevant detail as I can.

I have a 2011 D40 ST (Thai version). I've recently had a plethora of issues with it that has caused it to spend the last few months in and out of various workshops. Unfortunately after all the $'s I've thrown at it, it's still not 100%.

The wear and tear that was the catalyst to all this probably started earlier but I noticed the issues begin in early October during a trip across the Simpson Desert. That is; being slow, blowing a heap of smoke, and going into limp mode (I could fix limp mode by restarting the car). It wasn't very fun having to drive all the way back to Melbourne like that.

On the way back I saw the "water in fuel" light flicker very quickly. I actually had to look it up as I'd never seen the icon before. We went straight home. The car seemingly deteriorating more and more the closer we got to Melbourne.

When I got back I immediately booked the car into my mechanics. He removed the fuel filter and found a fair amount of water in it. Apparently I managed to fill my car with contaminated fuel at some point on the trip.

The mechanic tried a few things to fix my issues. He put in a new boost controller and checked for boost leaks, but it was the MAF sensor that stopped it going into limp mode. Unfortunately the Nav was still dropping boost, felt sluggish and was blowing a lot of smoke. He suggested I take it to a turbo/injector specialist. Meanwhile I blanked off the EGR valve, but that didn't make an iota of difference.

The specialists were confident some of my issues were the result of injector failure, and agreed that the water hadn't done them any favors. I actually managed to get insurance to come to the party on this. They paid for the fuel system to be cleaned/replaced where required so I was pretty stoked - it did take a long time to get this sorted though ~1month, but the work was seemingly very thorough.

The issue of the boost drop (it spiked to around 19psi then dropped to 10) was apparently the car going into limp mode, if only for a short while. I was told the EGR valve (still blanked) was throwing an error when the boost started climbing. That needed replacement too. Bit annoying since I was planning on leaving it blanked anyway.

I was also told the timing chain was noisy, and being a known issue on these engines I opted to have it replaced. It was replaced with the better/stronger duplex chain from yd25.com.au so I shouldn't need to worry about that ever again.

So I got the car back after around 2 months (this was over Christmas too). Picked it up on a Friday afternoon and it still felt sluggish. I'd been driving around in a pretty quick car while mine was in the workshop so I thought it might just *feel* slow. Once I got a bit closer to home I was convinced this wasn't the case. I'd started noticing huge plumes of black smoke behind me. I wondered if it just needed to go for a drive to bed in/re-learn or something (I was being optimistic). So off I went down the highway and through the hills, did about 260kms and it just felt like it was getting worse. By the time I gave it back to the workshop on Monday morning the smoke was ridiculous, a constant stream of black smog blasting out the back. At this point my fuel consumption was at 15.4 litres per 100km's of mostly open road driving.

They tinkered with it for a further 2 weeks, double checking their work and testing a number of things. They began to suspect the turbo was having issues but were hesitant to remove it due to the amount of work required. Eventually they ran out of other ideas and found out the turbo was damaged. The compressor blades had chips in them and it was filled with a fair amount of gunk. So I got a new turbo installed.

When I picked it up it still felt slow. Smoke is coming out when I take off almost all of the time (relatively little) and a puff between gear changes on decent acceleration. I have an OBD2 bluetooth device so I plugged it in and had a look at how the turbo was behaving. It looked much better.

I decided to go for a decent drive over Australia day weekend ~1,200kms of mostly highway in 100/110km zones. First fill had used 12.8 litres per hundred, second 13.7, third 11.3. Seems that it uses a lot more cruising in the 110km zones. Either way it's not in line with what I had measured before leaving for the Simpsons desert trip. I wasn't carrying a heavy load and didn't have anything on the roof racks either.

I found the car was really struggling to get up hills. I was having to gear back a number of times and found I was putting my foot flat to the floor which is unusual. I'm avoiding towing my boat with it at the moment as I think it will really struggle.

So, after all these things have been replaced, and all this investigation has been done does anyone have any suggestions on what I can do next? Do I fork out for a proper tune? Does the computer need to be reset? Almost feels like it's suffocating.

So far:
  • New injectors, common rail, fuel pump, filter etc
  • Cleaning of the fuel system/tank etc
  • New turbo
  • New MAF sensors
  • New boost controller
  • Compression tested twice
  • Exhaust removed and inspected (I don't actually know what they were looking at).
  • EGR valve replaced
  • Intercooler cleaned and pressure tested.

Here's some pics...

https://imgur.com/a/oiQaO
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  #2  
Old 02-02-2018, 12:50 PM
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Hey mate. Definitely sounds like a saga. It hasn't been mentioned but has the intake been checked for restrictions? How old is the air filter or is it new? Have you had the boost checked since having the new turbo fitted to make sure it is boosting properly?

Black smoke means it is "running rich," too much fuel for the amount of air present. You need fuel to make boost, so the computer throws fuel in when you start moving off to get the turbo spooling. You normally get a bit of smoke on take off before the turbo spools up and a small amount on gear changes as the fuel pressure increases faster than the turbo spools. If you have a noticeable amount when driving though I'd suspect either an intake restriction or leaking injector.

Something definitely isn't right with the power loss either by the sounds of it, so I'd start by checking the intake and replacing the air filter if it hasn't been already. Then check the boost pressure and go from there.

I should also add, having had the timing chain replaced, it would pay to have the timing double checked. If they have fitted it without lining up the timing marks correctly you may have a timing issue that the ecu can't correct.

Last edited by bods; 02-02-2018 at 12:52 PM.
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Old 03-02-2018, 02:06 AM
Vomitbomb Vomitbomb is offline
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Hi bods,

Quote:
Originally Posted by bods View Post
Hey mate. Definitely sounds like a saga. It hasn't been mentioned but has the intake been checked for restrictions? How old is the air filter or is it new? Have you had the boost checked since having the new turbo fitted to make sure it is boosting properly?
The air filter is brand new. I just opened it all up again and had a look and poked through the snorkel, definitely can't see or feel any obstructions. Air filter is still very clean.

Quote:
Originally Posted by bods View Post
Black smoke means it is "running rich," too much fuel for the amount of air present. You need fuel to make boost, so the computer throws fuel in when you start moving off to get the turbo spooling. You normally get a bit of smoke on take off before the turbo spools up and a small amount on gear changes as the fuel pressure increases faster than the turbo spools. If you have a noticeable amount when driving though I'd suspect either an intake restriction or leaking injector.
I can't see anything while I'm cruising along. It's definitely got a lot better. Just wanted to point out that I still got *some* black smoke, however insignificant. I've read that some of the D40 owners see a little bit, others don't see any at all.

Quote:
Originally Posted by bods View Post
Something definitely isn't right with the power loss either by the sounds of it, so I'd start by checking the intake and replacing the air filter if it hasn't been already. Then check the boost pressure and go from there.
I've checked the boost pressure using the Fusion app and an OBD2 bluetooth adapter. I'm not sure if that's an accurate reading or not but it seems to be fine.

Quote:
Originally Posted by bods View Post
I should also add, having had the timing chain replaced, it would pay to have the timing double checked. If they have fitted it without lining up the timing marks correctly you may have a timing issue that the ecu can't correct.
I did ask them about this actually and I can't remember if they got around to double checking their work. I was told that even if it was a tooth out it'd throw an error (I can't see one). Not sure how to check the timing on these though. It's going in to a 4x4 specialist next week to have some other stuff looked at so perhaps I can ask them to check for me.
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Old 03-02-2018, 12:53 PM
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Yeah it might be worth it. If everything is working as it should then there may not be anything wrong. Something definitely doesn't sound right though.

The ones that get no smoke are normally the ones fitted with dpfs as they catch the soot that you see as smoke. As far as I'm aware these were only fitted to auto models in a certain year range
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Old 05-02-2018, 08:56 AM
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Old.Tony Old.Tony is offline
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You've replaced just about everything that causes these dramas except for the vacuum hoses. I'm not sure if the 2011 Thai builds used a vacuum turbo actuator or the electronic one - the electronic ones from 2011 fitted to Spanish D40s had some troubles but these were replaced under a recall (and of course some cars could slip through the cracks).

Vac hoses are a PITA. I've replaced mine 3 times (285,000km clocked up on the way home from Bathurst earlier today). $20 at AutoBahn for 3m of 3mm ID vac hose - $15 at Supercheap and I can't tell the difference between the two, really.

Carefully examine the EGR pipe (gold tube that runs around the front of the motor). If they replaced the valve they may have removed the block. If there's an issue with the EGR pipe, you could be losing exhaust pressure (which drives the turbocharger). You can usually spot issues with the EGR tube because they leave black soot where the exhaust is escaping. This will reduce your boost levels.

Something else that affects boost (and therefore power, and air for combustion, and therefore the amount of smoke) is the dinky little gasket on the exhaust manifold where the turbocharger bolts to. Mine has twice turned into a reed instrument - at certain engine RPM it sounded like a very, very poorly played clarinet. You should notice the sound!
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Old 06-02-2018, 10:54 AM
240voltz 240voltz is offline
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I am having some power issues too. Spanish D40 auto diesel 2008

I have no power/acceleration when I plant my foot and I can barely go faster than 100km/h. Only started happening the day before I got my SCV changed.

I think I reset the ECU. Its not throwing any codes. I recently have had the battery disconnected to change my spiral cable and I had my parker lights out so I have played with the "hidden fusebox"

Is there anything obvious I should be looking at? Before I let the mechanics have a play.
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Old 06-02-2018, 02:18 PM
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i had much the same problem. could be the boost control solenoid, or the hoses going to and from it, mine were perished and split. disconnect the hose to turbo actuator at the BCS, and suck on it to make sure the actuator moves freely!
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Old 06-02-2018, 09:27 PM
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That's the most common problem, and would be my first port of call.

Test as Eric describes so that you're sure that:

* the actuator works
* the vanes move

then any problem is either turbo failure (yes, it happens) or control failure. Diagnose control failure like this:

* start the engine and watch the arm under the turbo. At idle, it should go in and out of the actuator irregularly and constantly. If not, get someone to give the accelerator a quick tap or two (no more than 2000rpm needed, so a light tap is sufficient). If the actuator moves, the turbocharger itself may be suspect.

* if there's NO movement at this point, find the vac hose that connects the vac pump (vehicle right hand side of the engine) to the BCS and disconnect it from the BCS, connect it to the actuator and fire the engine up again. If there IS movement, the BCS (or vac lines) may have failed. Replace the vac lines first (3m of 3mm vac hose, $15 at SCA, $20 at Autobahn) and if it's still not working, the BCS needs to be replaced.

Replacing the BCS: you can either just buy a replacement (genuine: $280, aftermarket, $??) or use a different system like the Tillix valve (www.tillix.com.au, $160). I am using the Tillix valve myself, it's reliable as long as you take precautions: you MUST use all-new hosing, and you MUST clamp the hosing that is subjected to boost pressure (the one that connects the black Tillix valve to the charge air pipe).

Check the turbocharger: with the engine off, remove the hose from the front of the turbocharger and using something soft (like a clean wooden spoon handle) give the impeller a prod. You shouldn't be able to make it wiggle much and it should turn fairly easily. If you can get your finger in to it, try turning it and see if it feels smooth. Any large wiggle movement or roughness indicates worn bearings and a turbocharger that is ready to let go.
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Old 07-02-2018, 09:21 AM
240voltz 240voltz is offline
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Thanks guys. The hose for the actuator to the BCS was buggered at the actuator. Replaced and now running pretty good. Will do the rest of the hoses once the temperature here drops (40 Degrees today)

Thanks again. Saved me a trip to the mechanic
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Old 07-02-2018, 11:54 AM
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Quote:
Originally Posted by 240voltz View Post
Thanks guys. The hose for the actuator to the BCS was buggered at the actuator. Replaced and now running pretty good. Will do the rest of the hoses once the temperature here drops (40 Degrees today)

Thanks again. Saved me a trip to the mechanic

don't forget to check these hoses on the drivers side, need to take the engine cover off check!


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