So a week or so ago my 2001 Subaru liberty b4 started jolting violently when I'd go above around 4000 revs. That's since gone away but now every time I go above 2,500-3000 revs or around 0- minus 10 vacuum, I hear sort of a honking noise which continues until I take my foot off the accelerator. I feel like the primrary turbo still spools, tho the secondary doesn't kick in at all and I'm not making any boost on my gauge. I think it may be a boost leak but have no idea where to start looking. Iv attatched a video, the sound is a lot pounder than it sounds. If anyone can help, it would be much appreciated.
Boost leak??
Started by Mmmbye, Jun 27 2017 09:25 AM
14 replies to this topic
#2
Beckers
-
- Members
-
- 3,058 posts
OMAR Cubt
- Gender:Male
- Location:South of the border, Blackburn
- Interests:Docking and eating dry meat, Living lyf in the TT VOD
Posted 27 June 2017 - 09:32 PM
The secondary will not kick in at those revs m8.
I get a sound like that between 2 and 2.5k rpm, almost like the exhaust is hitting the floor.
#3
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 28 June 2017 - 08:47 AM
Yeah I know it won't kick in then. That's just wen the sound starts. Then it just revs through. This sounds deffs coming from the engine bay
#4
Beckers
-
- Members
-
- 3,058 posts
OMAR Cubt
- Gender:Male
- Location:South of the border, Blackburn
- Interests:Docking and eating dry meat, Living lyf in the TT VOD
Posted 28 June 2017 - 06:20 PM
Does it happen in all gears or only when you change from 1st to 2nd ??
#5
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 28 June 2017 - 06:35 PM
All gears. I was thinking it was a boost leak but I got my mechanic mate to have a quick look and listen and he said it doesn't sound like a boost leak and said he'd never heard it in a car before
#7
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 29 June 2017 - 05:39 PM
yeah sorry I thought it uploaded
Attached Files
-
trim.17505233-87CF-4870-953F-1F70680CE93F.MOV 4.29MB
15 downloads
#9
duncanm
-
- Members
-
- 2,009 posts
wha' who ?
- Gender:Male
- Location:Sydney
Posted 29 June 2017 - 08:54 PM
If you suspect a boost leak - do a smoke test; pressurise the intake with some smoky stuff and look for leaks.
There's plenty of places it can occur.. if you're getting no boost at all and a funny sound, your diagnosis is probably correct.
Then again - sounds like someone let off a sneaky one in the car.
#10
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 30 June 2017 - 06:33 AM
Yeah I'll have to look into it. Yeah I thought that too haha
#11
Guest_KONG_*
Guest_KONG_*
-
- Guests
Posted 30 June 2017 - 06:39 AM
I know that noise. My car made it when I had a dodgy plastic turbo intercooler pipe.
Have you had the inter cooler off recently?
Have a good look at the pipes to see if they are on properly and check the hose clamps are done up real tight.
If that doesn't stop the noise you may have to remove the IC and inspect them further.
Have you had the inter cooler off recently?
Have a good look at the pipes to see if they are on properly and check the hose clamps are done up real tight.
If that doesn't stop the noise you may have to remove the IC and inspect them further.
#12
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 30 June 2017 - 12:22 PM
Oh righto. Nah I haven't. Okay I'll have a look, thanks Kong
#13
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 17 July 2017 - 05:36 PM
Update on the na b4. Iv replaced the hose that goes from the stock BOV to the intake cuz the original was hard and had a kink in it. I also took the intercooler off and inspected the pipes under. On the end of the intercooler to secondary turbo pipe it was split in two spots and had folded in if that makes sense. That was folded back out and taped and the intercooler put back on. Anyway, none of that fixed the problem. Although I discovered today that as I hold a gear and go through the rev range itl sound like there's a big build up and when I get to 6000rpm or so I get boost momentarily before I have to change. Is there anything it could possibly be that I could check?
#14
Guest_KONG_*
Guest_KONG_*
-
- Guests
Posted 18 July 2017 - 09:41 AM
It's a good sign that you're getting boost above 6k rpm 
Replacing that secondary pipe should be a priority. It may not be the exact issue but the best scenario is that it is still leaking and the differential pressure sensor is not seeing enough boost for the ECU activate changeover.
It's important to eliminate this from the equation & It's best not to get too far ahead of yourself with diagnosing your problem until you are 100% sure that pipe is sealing.
But in the mean time, you should be individually checking all your vac lines for cracks/splits/holes and be reading up on how to put your car in diagnostic mode using the green plugs under the steering column so you can check some of the TT solenoids and valves are working.
Do you have a check engine light lit up on your cluster?
When you had the IC off did you remove the vac line to the IACV on the secondary hard IC pipe and did it make an audible sucking noise?
#15
Mmmbye
-
- Members
-
- 25 posts
New Member
Posted 19 July 2017 - 08:03 AM
Weirdest thing, I found out yesterday that once I hold the gear til 6k and hit boost, then change gear and keep giving it to it, I have boost from like 4500. But if I change after hitting boost and take my foot off, it goes back to no boost til 6k. But yes, I'll have to get a new secondary hose. And look into that diagnostic mode. Yeah I do get the check engine light more often than not. Nah I didn't do that and didn't have the engine running
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users
