Boost Leak Test Results

[ColdAudio]

Alright, just did a boost leak test and found my BOV leaking, saw small tear in line going to IM so just cut it, havent tested it since because I wanted to see from UICP after BOV to the rest of the car, now im stuck.

It only builds ~5 PSI of pressure, I can't hear any leaks at all, and there is no excessive crankcase pressure because there is no air coming out of the valve cover breather stem (the nipple on the passenger side of the valve cover, not the PCV valve)

Could the air pump I'm using not be powerful enough? Any ideas on what could be wrong/what to do next? Thanks guys!

 

[ColdAudio]

Would a compressor similar to this one be sufficient?

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00915310000

 

[oldman]

Would a compressor similar to this one be sufficient?

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00915310000

Yes that will work.

 

[ColdAudio]

The results are in! And things never look good

First Test: Went straight onto turbo, built 11 PSI, heard air hissing but could not pinpoint but heard echo of air movement with oil cap off listening into valve cover and friend said he thinks he felt a little bit of air.

Second Test: From the TB elbow forward, built 16 PSI, injector seals definitely leaking as was seen using soapy water. Didn't find any other leaks but will re-test after this is fixed. Where can I get replacements and what is the right part I need?

Oh, and I didn't hear any air coming out of the exhaust, but damn does that pipe stink!

Oldman, I'm lookin up to you bud, need some help from here Thanks!

 

[oldman]

1. Focus for now on the areas between TB and head. Remove the pcv hose and cap off the nipple on the intake manifold then repeat test, make sure you spray soapy water all around TB, IM and all vacuum hoses connected to them. If pressure increases (indicating the pcv was stuck open), replace the pcv with an OEM piece, injector seals and whatever the soapy water reveals.

2. Once the TB elbow test is satisfied, move the tester to the IC inlet and repeat process.

3. Finally, back to the turbo inlet. It's clear due to the pressure increase when you initially moved the tester from the turbo inlet to the TB elbow that some air is leaking though your turbo seal > oil return > oil pan but don't freak. It's normal for air to get past the seal during a static pressure test as long as it's not loosing oil during operation. Just make sure no part of the licp is leaking.

 

[ColdAudio]

1. Focus for now on the areas between TB and head. Remove the pcv hose and cap off the nipple on the intake manifold then repeat test, make sure you spray soapy water all around TB, IM and all vacuum hoses connected to them. If pressure increases (indicating the pcv was stuck open), replace the pcv with an OEM piece, injector seals and whatever the soapy water reveals.

2. Once the TB elbow test is satisfied, move the tester to the IC inlet and repeat process.

3. Finally, back to the turbo inlet. It's clear due to the pressure increase when you initially moved the tester from the turbo inlet to the TB elbow that some air is leaking though your turbo seal > oil return > oil pan but don't freak. It's normal for air to get past the seal during a static pressure test as long as it's not loosing oil during operation. Just make sure no part of the licp is leaking.

Phew, I was worried I may need a new turbo but I let my mind run off to the worst scenarios too quickly Just replaced PCV valve with one from dealership (not only do we get club discount, but on ocassion employee discount ) and will order injector seals in the morning. Hehe, thanks a ton once again oldman, wish there was something I could do in return for ya.

Also, just for personal knowledge, what would it have meant if I heard air coming through the exhaust? That both the intake and exhaust valves are open at the same time, meaning the timing is off?

 

[oldman]

Also, just for personal knowledge, what would it have meant if I heard air coming through the exhaust? That both the intake and exhaust valves are open at the same time, meaning the timing is off?

1. EGR valve is stuck open.

2. Valve overlap, occurs at the end of the exhaust stroke and beginning of the intake stroke when exhaust valves are just about to close and intake valves just started to open. To avoid this simply turn the crank to 30* after TDC.

With that said, obviously off timing or bent valves can also cause air leaking out of exhaust but a compression test will easily pick that up.

 

[ColdAudio]

Ah ok thanks very much for the info, my buddy at the dealership ordered everything today and will get it tomorrow, should be done by tomorrow night for more testing!

 

[ColdAudio]

oh do i need to relieve the fuel system of pressure if im just changing the injector seals?

 

[oldman]

oh do i need to relieve the fuel system of pressure if im just changing the injector seals?

Why not, just in case if the injectors falls out of the rail. If this happens, make sure you change the upper o-ring as well and grease it before re-install.

To realease the pressure:

1. Open the fuel cap.

2. disconnect the fuel pump harness in the trunk.

3. start the car and let run until it stalls.

 

[ColdAudio]

alright i swapped out the injector insulators, but man do i gotta say there is absolutely no room to move that fuel rail! ended up disconnecting from filter and just sliding it out of the way.

results: idle is a bit lower and a bit steadier. less popping sounds at idle/deceleration(misfires?). vacuum a bit steadier. still at only ~14hg at 950-1000 rpm, but thats up from 10hg so I'm getting there will retest tomorrow when i can get the right attachment for the compressor to go onto a valve stem

anything else i should do in the meantime?

EDIT: well it's the next morning, my idles going nuts surging and is really high, and all the popping noises are back

 

[ColdAudio]

A possibly related question: Can a vac leak cause misfire?

 

[oldman]

The best thing to do right now would be to concentrate on finishing the leak test first so boost leak can be eliminated completely. While you do that, I'll review this thread again and figure out what would be the next step if problem persists after the leak test is complete.

 

[ColdAudio]

Alright sounds good oldman, thanks

 

[ColdAudio]

Alright well I tried to do another test today but everybody I know refused to lend me a hand. I got my brother to help me for 5 mins, built 17 PSI at TB Elbow, saw very slight bubbling by cylinder #4 at either IM or injector insulator, but i just replaced the insulators. Couldn't tell which they're so damn close together. I doubt I would know how to take the IM off, it looks difficult, but I guess I'd be willing to try anything with a little guidance, if you have any?

On a related note, I've been reading all sorts of old threads today on timing since I've got insane advance up to 40* and causing alot of knock (but the sensors bad I believe). When I parked my car in my driveway today I popped off the timing belt cover and there it was, both dowel pins at TDC or maybe 1/4 degree off. Timing marks were 1 tooth off. But I didn't crank the motor at all to try all possible positions because I don't know how to manually crank the motor! Guidance on this is also needed Oh yeah, and if you'd like, I did take pictures of the timing just incase. Let me know, thanks!

 

[oldman]

Alright well I tried to do another test today but everybody I know refused to lend me a hand. I got my brother to help me for 5 mins, built 17 PSI at TB Elbow, saw very slight bubbling by cylinder #4 at either IM or injector insulator, but i just replaced the insulators. Couldn't tell which they're so damn close together. I doubt I would know how to take the IM off, it looks difficult, but I guess I'd be willing to try anything with a little guidance, if you have any?

It's up to you to figure out if it's the insulator or the IM gasket. If it's insulator leave it. If it's the gasket, I would fix it. It's not hard but just a PITA, with proper tools and a service manual, you should be able to handle it. Don't forget to move the tester back towards the turbo after the TB test. BOV and J-pipe gaskets are two of the most common leaks.

When I parked my car in my driveway today I popped off the timing belt cover and there it was, both dowel pins at TDC or maybe 1/4 degree off. Timing marks were 1 tooth off. But I didn't crank the motor at all to try all possible positions because I don't know how to manually crank the motor! Guidance on this is also needed Oh yeah, and if you'd like, I did take pictures of the timing just incase. Let me know, thanks!

Are you saying the timing is off by on tooth or it's one tooth off from being TDC?

 

[ColdAudio]

Are you saying the timing is off by on tooth or it's one tooth off from being TDC?

At basically perfect TDC (what luck i turned the engine off that way ), the timing was 1 tooth off

 

[Strm Trpr]

With that said, I'd take all of the T-Belt covers off and really see what's going on with the timing of the crank,
oil pump, b-shaft (if not eliminated), and camshaft sprockets.
Make sure everything lines up with the cam dowels at 12 o'clock.

But first, let's get to work on that IM gasket issue.
I doubt if it's your injector insulator, you just replaced them.

Find out the torque specs for the IM to head interface.
Keep in mind that someday you may be replacing the IM gasket, but for now just re-torque the screws.

Then re-boost leak test from your TB and look for bubbling.
Hopefully your vac issue will be solved.

Next, test at the IC input from your turbo, this will help isolate your BOV and your IC.

Then finally recheck at the turbo intake to make sure the LICP and the J-pipe gasket aren't leaking.

Good Luck....

 

[ColdAudio]

With that said, I'd take all of the T-Belt covers off and really see what's going on with the timing of the crank,
oil pump, b-shaft (if not eliminated), and camshaft sprockets.
Make sure everything lines up with the cam dowels at 12 o'clock.

But first, let's get to work on that IM gasket issue.
I doubt if it's your injector insulator, you just replaced them.

Find out the torque specs for the IM to head interface.
Keep in mind that someday you may be replacing the IM gasket, but for now just re-torque the screws.

Then re-boost leak test from your TB and look for bubbling.
Hopefully your vac issue will be solved.

Next, test at the IC input from your turbo, this will help isolate your BOV and your IC.

Then finally recheck at the turbo intake to make sure the LICP and the J-pipe gasket aren't leaking.

Good Luck....

That's actually a good idea with re-torqueing the bolts so simple yet definitely a possible fix I plan on testing the rest this weekend hopefully on Sunday, god damn tuition makin me work 16 hour days.

Now about timing issues: I went to my buddy's house this weekend to use his timing light and saw that base timing was set at 15* BTDC!! Set it to the correct 5, idles kinda rough with only 10 hg in vac but idle no longer surges, stays in generally the same area, timing is no longer insanely advanced, and combined with new knock sensor and new fuel filter, no more knock issues and alot less of the misfire popping noise. Did not have a chance to check how timing lines up though. I'm thinking it's possible whoever did last timing job advanced timing enough to make up for vac loss from misaligned cam gears? We will find out shortly!

Thanks again for all the help guys. Oldman i'll get that pic up tonight when I get home.

 

[Chaddycakes21]

1. What size compressor? Maximum psi?

2. Did you spray soapy water all over the TB, intake gasket, injector seals and all vacuum hoses?

3. Remove the oil cap and stick your ear in there during test and listen for leaks.

4. Stick your ear in the tail pipe and listen for leaks.

I know this is an old thread but should you hear/feel air coming from the tail pipe?

 

[oldman]

I know this is an old thread but should you hear/feel air coming from the tail pipe?

No, please read post #31.

 

[Chaddycakes21]

So should i perform a compression test? OR turn the crank to 30* after TDC??? Because there is def. air coming out my tailpipe.

 

[oldman]

So should i perform a compression test? OR turn the crank to 30* after TDC??? Because there is def. air coming out my tailpipe.

Is your EGR blocked off already? If not, I would remove and clean it to make sure it isn't stuck open. If it's already blocked off, I would first make sure the engine is at 30* after TDC and follow through with a compression test if the problem persists.