down on power?

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ericcs

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My 06 D40 auto feels like it's down on power. No codes, starts/stops as normal, makes boost, and doesn't miss a beat.
It has a full 3" exhaust with muffler, which strangely now sounds loader, and a snorkel. I also recently fitted a new boost control solenoid, otherwise I can't see anything abnormal!
 
I'd suggest a couple things to check first. Is there any extra soot coming outta the exhaust. If so and it's thicker then normal and black make sure the air filters not too dirty or a blockage in the air in.
If you just installed a boost contoller, make sure there's no leakage. Possibly an overtight clamp thats pinched the house open.?
 
As above. There are more things to check/do:

* Clean the MAFS sensor
* Run some Liqui Moly Fuel System Treatment through a tank of fuel
* Clean the intercooler
* Check the EGR block in case it's developed a hole

Observations about smoke are important. When you replaced the BCS, did you do anything with the vac hoses?
 
I'd suggest a couple things to check first. Is there any extra soot coming outta the exhaust. If so and it's thicker then normal and black make sure the air filters not too dirty or a blockage in the air in.
If you just installed a boost contoller, make sure there's no leakage. Possibly an overtight clamp thats pinched the house open.?

haven't noticed anything more than the usual puff when i take off.
it probably could do with a filter change, and with the BCV, there are no clamps for the hoses, as they just push on, however, they have never been changed.
 
As above. There are more things to check/do:

* Clean the MAFS sensor
* Run some Liqui Moly Fuel System Treatment through a tank of fuel
* Clean the intercooler
* Check the EGR block in case it's developed a hole

Observations about smoke are important. When you replaced the BCS, did you do anything with the vac hoses?



before i changed the BCS, the car fluctuated in power, but once i changed it, the car ran like a dream. now it just seams flat all the time. i will do the quoted cleaning, but just on the Liquid Moly, i did it earlier this year, so would it need doing again so soon?
regarding the turbo, i checked the free play some months ago. i had no end float play, but noticeable side play, but not enough to rub on the housing. so, how much is too much?
Lastly, is it recommended to do do the relearn at any stage?
 
You can do the relearn as often as you like, it doesn't do any harm. If you've done the fuel system clean this year you'd expect that wouldn't be needed unless your SCV was playing up or you've filled up with some less than stellar fuel.

A small amount of play on the turbo shaft is ok, if it's more than 1mm I'd be looking for a new one. My original turbo had about 1mm play on the shaft when I replaced it and when I tried refitting that turbo it let go in about 10 minutes. It now has about 10mm of play and of course won't rotate very well at all.

Have you tried (engine off) drawing the turbo actuator all the way up yourself? Remove the vac hose, get a clean new piece and attach one end to the actuator and suck on the other. It should fairly easily rise up - it moves quite a bit if it's in good nick. If it stops after 10mm or so then something's either making it stop (stuck/sticky vanes) or there's a leak in the actuator diaphragm which you'll know because you have to keep sucking on the hose to maintain the position of the actuator arm.
 
...and with the BCV, there are no clamps for the hoses, as they just push on, however, they have never been changed.

My apologies, I read it as a new boost controller
Try the other few things @Old.Tony listed as well. All pretty simple

Mine is also leaking from a dodgy clamp on the way into the intercooler, behind the grill on the passenger side. Even tho it looks tight I know the clamps stuffed
 
You can do the relearn as often as you like, it doesn't do any harm. If you've done the fuel system clean this year you'd expect that wouldn't be needed unless your SCV was playing up or you've filled up with some less than stellar fuel.

A small amount of play on the turbo shaft is ok, if it's more than 1mm I'd be looking for a new one. My original turbo had about 1mm play on the shaft when I replaced it and when I tried refitting that turbo it let go in about 10 minutes. It now has about 10mm of play and of course won't rotate very well at all.

Have you tried (engine off) drawing the turbo actuator all the way up yourself? Remove the vac hose, get a clean new piece and attach one end to the actuator and suck on the other. It should fairly easily rise up - it moves quite a bit if it's in good nick. If it stops after 10mm or so then something's either making it stop (stuck/sticky vanes) or there's a leak in the actuator diaphragm which you'll know because you have to keep sucking on the hose to maintain the position of the actuator arm.

thanks again Tony for your advice. I'll check the actuator first, and it's probably a good opportunity to replace all my vac hoses while i'm there.
I think you mentioned once, i'll need approx. 3m of 3mm hose?

Using my torque app., at idle, it'd drawing between -0.4 and -0.1 vacuum, and at best, 18psi of boost!
 
I'd suggest a couple things to check first. Is there any extra soot coming outta the exhaust. If so and it's thicker then normal and black make sure the air filters not too dirty or a blockage in the air in.
If you just installed a boost contoller, make sure there's no leakage. Possibly an overtight clamp thats pinched the house open.?



took it for a drive today with the window down, so I could see properly behind, and yes, it's choofing heaps of black smoke!
 
Since the boost is ok, it has to be fuel metering. And that's going to be:

1) MAFS
2) SCV
3) Injectors
4) Fuel Rail Pressure Sensor

The MAFS is highly suspect. Here's a trick to check if it's operating properly.

I've noticed that at 80km/h or more (with a snorkel - you might need to go a little faster, like 100km/h) the MAFS reads the same as the ambient temperature. If you don't have the ambient sensor, just a normal thermometer will do (in shade). Grab your Torque app and load up the Intake Air Temperature. Go for a drive and check the temp.

If the temp is close to the measured outside temp then your MAFS is likely fine. I suspect it may not be. The MAFS uses the voltage difference across a hot wire to determine how much air is flowing. As a wire heats up, its resistance increases and the voltage difference across the wire becomes greater. As air flows over the wire, it is cooled, lowering the resistance. Thus it is possible to measure the amount of air flowing past - as long as you know the temperature of the air.

That measurement is crucial. If there's dirt on the MAFS, the wire may show less resistance, which (as a sensor reading) indicates a greater cooling effect which is usually the result of more air. If the ECU believes there's more air moving in, it will increase the fuelling appropriately.

The answer to that is to clean the MAFS. Precautions shouldn't be taken lightly. Even if you can see the muck inside, do NOT EVER touch it. Just keep spraying more contact cleaner in the hole. I just found a thread on this that I wrote here. Pictures included.

Please let us know how it goes! I'm obviously assuming it's not going to be SCV/injectors or FRPS. This last one has been a sore point a couple of times, and may just be dirty contacts, but if you monitor fuel rail pressure in Torque as you're driving and you don't spot any spikes/dropouts while moving (try choosing a graph mode to see this) then the electrical connection is not suspect.
 
replaced the air filter and cleaned the MAF, then thought, nah, that's not going to fix it. So snooped around , and what did i find, the usual culprit.
Car is back to normal!

122om85.jpg
 
The tubing is like that so you can get the hose onto the tube. It's nice that it's at the top of the engine and not down near the vac pump (above the fuel pump, below the intake manifold). The hoses look like they weren't quite long enough. Your brakes must have been suffering too!

It's surprising that it boosted properly, but obviously not properly enough! I think I'll make it a mission of mine to replace that hosing every couple of years just to be on the safe side.
 
yeah, was strange, as understandably, there was zero boost under normal driving, but if i booted it, boost reading went up as afar as 18psi. now there is always some boost, even at idle, and shoots up to 21psi.
funny thing was people were asking me if iv'e had an exhaust fitted, as the car was much louder, and i couldn't hear any induction noise through the snorkel anymore. makes sense now, as the turbo vanes would have been open all the time.
Also, turning the engine off was more abrupt when it came to a halt, now it's smooth again!
 
replaced the air filter and cleaned the MAF, then thought, nah, that's not going to fix it. So snooped around , and what did i find, the usual culprit.
Car is back to normal!

122om85.jpg

can anyone help with a diagram, as to where the rubber hoses go to below the steel tubes. I cannot for the life of me see anything from above or below!
 
Eric, do you have a digital copy of the manual? Go to EC.PDF, page 1006. It's not perfect, but does show that there's a hose connection from the bottom to the vac pump directly, and another to the intake actuator.
 
thanks Tony. i had a look and EC 1006 is something to do with diagnostics for the engine coolant sensor, but found the diagram on page 918. it looks like on the diagram and on my car, one of the pipes is blanked off, with the other end going to the BCS!
 
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