Boost leak? Exhaust leak? I'm stumped.

[justin13703]

is this a popet style one bosch ect because thous will leak but the hks should stay shut in less you are pushing so much boost you are over riding the spring and need the extra help from vacumme

The mk3 superchargers use an hks blowoff valve.

 

[fishsticks]

Sorry, my order of operations may have been unclear.

First I tried the soapy water, looking for a boost leak. After I didn't find one, I decided to pull the belt off and go for a short (couple-few thousand feet) drive just to see if the noise went away with no boost present. I put the belt back on afterwards. Then I tried disabling the recirculation valve on the off chance that maybe it was making the noise even under vacuum.

The noise is definitely coming from the passenger side of the engine bay. I'm beginning to suspect the header flange is leaking out the bottom, where I wouldn't have noticed it when I initially plugged the exhaust to check for leaks there.

There's a lot of air moving from the leak, and I think if it were a vacuum leak I'd have set a code by now. Guess we'll see.

 

[Gadget]

Clearly something changed when you did the injector installation.

This means it is Something you did and just have to find it. What else did you do othar than injectors?

Time to start taking everything off you took off before and looking at everyting very carefully to find that one little thing that is not as it should be.

G

 

[fishsticks]

Clearly something changed when you did the injector installation.

This means it is Something you did and just have to find it. What else did you do othar than injectors?

Time to start taking everything off you took off before and looking at everyting very carefully to find that one little thing that is not as it should be.

G

That's my line of thinking as well. I did the headers on the same day.

Intake came back off yesterday. Everything checked and reassembled. Pulled the passenger side header this afternoon after work and replaced the gasket with a new one plus some copper RTV. Giving that some cure time before I start it back up.

I'm a PRO at getting to all those bolts now. :top:

 

[Gadget]

Check to make sure the air filter is properly sealed between the top and bottom of the air filter box. If it sucked in on one side I can see how you might get some noise there.

 

[Torspd]

Have you grabbed any spray yet?

 

[Blue10XR]

Have you grabbed any spray yet?

If you can hear it, what Torpsd said should let you find it rather quickly....

 

[fishsticks]

Doing some work on a family member's MDX this morning. I'll look at the Taco yhis afternoon and report back.

 

[fishsticks]

Used about a can of carb cleaner around every joint and all along the intake manifold. I have a very clean engine top now but found nothing.

Pulled the D/S header and checked the gasket. No signs of leakage there... Replaced gasket anyway and used RTV. No change.

Checked air box/filter. Nada.

Still no pending or current codes set. OBD data looks pretty normal in fact.

I'm starting to lose hope. It's been a lot of years since something has tripped me up this badly.

 

[Torspd]

.....well if it runs like a champ and performs like a champ......

 

[fishsticks]

.....well if it runs like a champ and performs like a champ......

Yep. I smoke tested the intake today and only got a little bit escaping at the air box. I'm going to pressure test the intercooler and if that turns up nothing, I'm done. I'll just convince myself it's turbulence across the throttle blade or something.

I need to get a real boost gauge anyway. The OBD reading has peaked as high as 14, but I don't trust it. Used to get 10 on the 80mm pulley and it seemed like it would build faster at lower RPMs. But it's all guesswork without a real gauge and a known value of what it should be.

 

[Torspd]

Hmm. Keep us posted on how the smoke test does on the other parts.

 

[Nashman]

back n the day these issue were easy to find when ya had a dyno

to bad my boss will not buy one :bawling:

haha

any who have ya done the home brew/cheap shop dyno yet ???


lift the truck rear axle place on jack stands drrr... lol pull ebrake but not fully just so it has a fair good amont of drag stick it into second and full throttle and ride the shit out of your brakes then releesh once loaded. use a stethoscope and start listen


other then that good luck or buy your self a gas can and pack of matches

 

[fishsticks]

Hmm. Keep us posted on how the smoke test does on the other parts.

I smoked the whole intake track already. Hooked a piece of hose to the brake vacuum port and human-powered some smoke into there. Then followed it with 10psi or so of air from the compressor to move it around.

back n the day these issue were easy to find when ya had a dyno

to bad my boss will not buy one :bawling:

haha

any who have ya done the home brew/cheap shop dyno yet ???


lift the truck rear axle place on jack stands drrr... lol pull ebrake but not fully just so it has a fair good amont of drag stick it into second and full throttle and ride the shit out of your brakes then releesh once loaded. use a stethoscope and start listen


other then that good luck or buy your self a gas can and pack of matches

That's... not a terrible idea actually. It's pissing rain today though and I already put the mower back in the shop. Maybe tomorrow after work.

Not ready to burn it yet. Still the best truck I've ever owned.

 

[fishsticks]

So this happened this morning while driving my son over to his mom's...

Borrowed the ex's car to run to my morning appt. On the way back I stopped by ETS (they are local to me) and they sold me a more robust clamp (for $20 bucks woo!).

Long story short. Got the new clamp in and put some copper RTV in for good measure. My leak is now QUIETER. :rockon: I was sure it was coming from farther forward but sounds lie in the cab sometimes.

Today was a hectic day so I only had time to put the clamp on with RTV and leave it for a few hours. I'll check for flange warpage or any of the other 43985734 reasons why V bands don't seal tomorrow maybe.

G-man, any critical reason why there is a V-band at the joint rather than a slip? If not, and I can't get it to seal up I may just grab a spool of SS wire, borrow some 98-2 and make it a solid joint.

 

[Torspd]

Hmm. Never seen that one before. Good thing ETS is so close to you. Lucky dog.

Quick release FTW. I hate those non quick release as they frustrate me with a passion. Person opinion. Still had one last one on the exhasut. Finally purchased a Burns Stainless to swap it out.

 

[fishsticks]

Hmm. Never seen that one before. Good thing ETS is so close to you. Lucky dog.

Quick release FTW. I hate those non quick release as they frustrate me with a passion. Person opinion. Still had one last one on the exhasut. Finally purchased a Burns Stainless to swap it out.

It was definitely a surprise. Lol. Oh well, weird stuff happens sometimes. I'm more embarrassed that I worked all around the issue instead of finding it sooner. I swear it's not my first day... :rolleyez:

I messed with the alignment of the flanges today and think it's sealed up as good as it's going to get. Didn't get much time for a test drive, but it sounds the quietest it has. I ordered boost and AFR gauges earlier this week and they'll be here tomorrow, so I'll poke at it then if need be. Made some calls and found a buddy with access to a TIG too, so I have the nuclear option available if it continues to leak there.