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threedogs
19th October 2012, 04:14 PM
Hi all not overly concerned but lately I've Been able to hear the turbo a bit louder. at first thought noise was coming through the radio. Read another member had a similar problem and they said leaking intercooler. Now I get a sound like I have a blow off valve fitted, and constant cold/hot its the same. Gee I hate these computer cars. any ideas would help

nissannewby
19th October 2012, 04:41 PM
It does sound like a boost leak. Also check your intake into the turbo make sure it hasn't been dislodged.

threedogs
19th October 2012, 04:45 PM
Thanks mate I'll take the cover off tomorrow and check everything, boost is set to 14psi and it goes great.
just that very annoying sound,

Yendor
19th October 2012, 04:55 PM
Also have a look around the EGR valve and pipe for leaks.

If you have a major boost leak you should be able to pick this up by your boost gauge.

threedogs
19th October 2012, 04:59 PM
Boost seems normal but after I remove the cover I'll run a spanner over everything thanks mate. everything mentioned is all I have touched with NADS etc

threedogs
20th October 2012, 01:43 PM
Rightio, removed engine cover, looked normal. checked hoses all were ok, checked egr {blocked} all tight.
other than trying a bigger hammer I'm at a loss.
One thing I did notice was at 2000rpm normally I have 10LB psi. now its 5LB psi. losing pressure as suggested.
so taking it the IC is knackered as everything else looks ok. Thoughts please,
gee I hate these things.

Yendor
20th October 2012, 03:00 PM
That drop seems very high to be caused by a leaking IC.

Did you check that all the hoses are still on the flanges correctly?

threedogs
20th October 2012, 03:29 PM
Yeah They look good other than R and R I just nipped clamps, will check again Thanks Yendor

Split hose maybe but appear in good nick.?

Yendor
20th October 2012, 03:39 PM
Possible, My IC was leaking for over 2 years before I replaced it and it and I never had a drop in boost like that.

It would have to be a fare size hole.

When a hose on mine partly dislodged on the IC flange, boost was about halved.

You may also need to start looking at the turbo.

threedogs
20th October 2012, 03:45 PM
Don't say that as I'll sell it. Got no $$$$ for a turbo fix

Yendor
20th October 2012, 03:58 PM
Don't say that as I'll sell it. Got no $$$$ for a turbo fix

I hope it's not too, mate.

Double check for leaks, hopefully this will sort it.

If not, I'm sure the guru (yes that's you Matt) will be along to help.

threedogs
20th October 2012, 04:49 PM
Me Three , one thing I have noticed, where I've TEEd off the Dawes To Boost guage i used that pretty red silicon hose.
May be thats expanding under boost , I'll replace tomorrow with 3mm EFI fuel line, plus recheck hoses, thanks

nissannewby
20th October 2012, 11:34 PM
If its a loss like that it will be a noticeable hole or leak for that amount of drop. Can you get a clip of it running so I can hear it? It would pay to pull the intake off your turbo and check it for excessive play. Other than that it could be something to do the actuators for your vnt or possibly a spring in your needle valve losing tension?

threedogs
20th October 2012, 11:42 PM
I'll re adjust the needle valve,etc makes no noise goes great just that pituuuuh noise like a blow off valve
doesn't sound expensive in any shape or form

nissannewby
21st October 2012, 01:21 AM
Have you recently put a new snorkel or air cleaner or something like that on it?

threedogs
28th October 2012, 10:57 AM
Found it thanks to Newby and Yendor putting me in the right direction. Thanks Guys
Appears a poor weld, but I'll take it back to the exhaust place and see what they have to say.
Only had sport cat and EGT guage fitted not long ago.

macca86
28th October 2012, 12:11 PM
Yeah I was stung hard for a turbo earlier this year not cheap if you can't do it yourself. What about the actuator hoses and wastegate stuff just off the turbo or a crack in the boost gauge fitting where its welded or a part air blockage in the intake

threedogs
28th October 2012, 12:16 PM
Macca can't you see crack in pic, I'll have to take a better picture. I've PM'ed Newby for further advice
I'm not a T/D guy, but slowly getting the hang of them

nissannewby
28th October 2012, 12:46 PM
Should have looked at this before responding to your pm. The crack looks like its actually in the exhaust housing of the turbo itself :O. If you were to unbolt your dump pipe from turbo the crack would still be there wouldnt it? Hopefully Im looking at it wrong and its only cracked around the weld for mounting flange on your dump pipe.

macca86
28th October 2012, 12:46 PM
Macca can't you see crack in pic, I'll have to take a better picture. I've PM'ed Newby for further advice
I'm not a T/D guy, but slowly getting the hang of them

I was writing my response when yendor was the last post well it was on my phone then all the other posts showed up

threedogs
28th October 2012, 01:05 PM
I'll go have a very good look,

threedogs
28th October 2012, 01:24 PM
Looks bad from that angle but its only cracked at the back of the mounting flange on the cat side, Turbo is ok.
Have to take it back to shop as not even one year old. Plus I cant get under 4x4 if I tried
Should there be a flexi joint???

nissannewby
28th October 2012, 01:38 PM
This is the one that caught my eye.

http://i1248.photobucket.com/albums/hh493/nissannewby/Turbocrack.jpg

threedogs
28th October 2012, 02:01 PM
Just triple checked it looks like crack in pic but its just the writing on the cast body of turbo and angle of pic

Yendor
28th October 2012, 06:04 PM
Going by the soot on the weld I would say you have found your noise.

Good job mate, looks like it will be a cheap fix too, even better.

threedogs
28th October 2012, 06:17 PM
Yeah All good thanks Yendor, its under a year so hope they come to the party with the fix,
Should I have a flexi joint in the exhaust , ????

Yendor
28th October 2012, 06:31 PM
Yeah All good thanks Yendor, its under a year so hope they come to the party with the fix,
Should I have a flexi joint in the exhaust , ????

Sorry I don't know, to me that weld looks like a dog breakfast.

threedogs
28th October 2012, 06:40 PM
It looks like a cast iron elbow, will know soon enough, as weld looks like its snapped the metal

Yendor
28th October 2012, 06:51 PM
Yeah I can see what you mean especially on the lower part of the pipe in the photo, it looks like the pipe has broken away with the weld.

It's just strange there is no soot on the pipe around this area.

nissannewby
28th October 2012, 07:07 PM
Yeah All good thanks Yendor, its under a year so hope they come to the party with the fix,
Should I have a flexi joint in the exhaust , ????

Most have a flex joint in them between the turbo and first exhaust mount on the chassis to help prevent things like this happening.

threedogs
28th October 2012, 07:11 PM
Thats what I thought, I'll mention it when "discussing repairs" very happy only crack and not something more $$$$$$$$$
Worse comes to worse I'll get the guy up the street to remove it and I'll weld it up
Looks like that elbow has cyrstallised as looks very brittle

boots
28th October 2012, 07:29 PM
Hi John . Mine is still factory exhaust and it has flexi between the bottom of the cat and the muffler . right near the first flange from the dump pipe . factory dump pipe also has a bottom mount bracket that goes to the side of the block . this bracket would help share the stress with the turbo flange bolts and vibration . Does yours have this ?

threedogs
28th October 2012, 07:35 PM
Hi mate I'll have to get back to you on that as No way I'm able to get under 4x4 ATM
I have no OE exhaust left. maybe they got lazy and left it off. rrrrrs holes

threedogs
29th October 2012, 11:05 AM
Up date , I took it back and explained my concern. didn't bat an eyelid.
Put the Patrol on a hoist removed the bit, cut off and re welded new elbow ,he also re welded
a broken support bracket . zero, nada ,zilch So 2 thumbs up for True Flow Melton.

As well he noticed oil at the back of the IC , so I'll need to check the lower boost hose.
Also and under the oil filter I'm led to believe there is a drip plate that drains through a rubber hose??
he said its an engine breather and I have blow by, What the?? As I'm not that mobile at the moment I cant get under to check it.
drip tray yes see pic

nissannewby
29th October 2012, 08:40 PM
I would say its just a drain tube for your filters as you have a catch can fitted and your engine breather is plumbed into your intake again after the catch can. As for the repair is she all nice and quiet again now?

threedogs
2nd November 2012, 12:28 PM
Yeah Newby ,nice and quiet again thanks. I'll be tightening up the filter a tad and checking the
oil leak out over the weekend. very minor things but other than that all is good.

Sir Roofy
2nd November 2012, 12:37 PM
yeah newby ,nice and quiet again thanks. I'll be tightening up the filter a tad and checking the
oil leak out over the weekend. Very minor things but other than that all is good.

hi td sorry mate meant to get back to you about the pipe in the pic
lol, oldage creeping up its the drain pipe from the spill tray under the filter
when you crack open the filter the oil goes into the tray instead of down the side of the motor

threedogs
2nd November 2012, 12:45 PM
Ok thanks Roofy funny bit is the young guy doing exhaust, swore black and blue my 4x4 had BLOW BY
and I should take it to a shop for a compression test. I wet myself and he was very serious, tried telling him
but he wouldn't hear it ,,RLMFAO