I have a boost leak.. but not sure where

[hun6over]

So today i did my first boost leak test. I used the gauged boost leak tester from boostpro. Using a bike pump, i pumped the pressure up as much as I could and couldnt get past 5 psi. Even though the psi was only at 5, i could hear a hissing sound coming from my engine. I checked to see where the hissing was coming from and i found it to be loudest when i put my ear on the valve cover.

Anyone have any idea if this is normal?

 

[eboy0]

Check your pcv valve, it may be leaking.

 

[The_EE]

PCV isnt the whole problem, the bike pump is. You cannot expect to pressurize the entire system in the car with a bike pump, you need a compressor to do the job. If you do not have a gauge on the leak tester then you will need a second person looking at your autometer or equivalent boost gauge, the stock one on your dash will not do.

 

[eboy0]

PCV isnt the whole problem, the bike pump is. You cannot expect to pressurize the entire system in the car with a bike pump, you need a compressor to do the job. If you do not have a gauge on the leak tester then you will need a second person looking at your autometer or equivalent boost gauge, the stock one on your dash will not do.

Well before I got myself a working compressor, a bike pump did just fine to test from TB and up, but yes to test from turbo inlet you need a compressor or a tank w/ compressed air.

 

[hun6over]

OK, i understand that i need a more powerful way of pressurizing the intake. With the bike pump, i was able to make enough pressure to create signs of a leak. What i want to know is if it is in fact a leak and where it could be coming from.

I do have a electrical air compressor. The one that is used to pump the tires on cars. It hooks up to the cigarette lighter inlet of the car. Would that work? Well, i tried using it but i wasnt able to build more that 2psi for some reason. That is why i stuck with the bike pump.

 

[kmoore]

Go to walmart and get yourself an air compressor real cheap. When you do get your air compressor and pressurize the system 5psi more then you normally run, take off your oil cap and put your ear in the hole. If you hear air down in there it is your PCV Valve. I also would put money that you are leaking through your throttle body shaft seals also.

 

[oldman]

Go to walmart and get yourself an air compressor real cheap. When you do get your air compressor and pressurize the system 5psi more then you normally run, take off your oil cap and put your ear in the hole. If you hear air down in there it is your PCV Valve. I also would put money that you are leaking through your throttle body shaft seals also.

Air leaking into crankcase when testing from the turbo inlet can be turbo seal (normal as long as there is no excessive shaft play), PCV, valve seals or piston rings.

Here is something that will help you in method, procedure and expectaion.

1. Disable your mbc.

2. Turn your motor to 30* ATDC to avoid valve overlap.

3. Start your test at the TB elbow and focus on area behind the TB first.

4. Spray soapy water at TB gasket, BISS, TB shaft on both sides, IM gasket, injector insulators, brake booster, afpr and all vacuum lines/connections.

5. Open your oil cap and listen for leaks. (PCV, valve seals/guide, rings)

5. Listen to your tailpipe for leaks. (EGR, valve overlap, jumped timing, bent/unseated valves)

6. Once all leaks are fixed, move the tester back to the turbo inlet.

7. Spray down the compressor cover (known leak), BOV return/flange (DO NOT TAP YOUR BOV LINE FOR YOUR MBC!!!), IC end tank/fins and all connections. Re- test.

8. Note that you will leak air into the crankcase through the turbo seal but do not panic, this is normal during a static pressure test as long as there are no shaft play.

The desired test result from the begining of the LICP (bypassing turbo) is around 20psi (on boost gauge) with the compressor set at 30psi, while taking no less than 30 seconds to bleed down to 0.

As a reference, my last test on my 500 mile new engine, I was able to pressurize the system to 25psi, bled down to about 16psi (my 1G bov) in about 30seconds, then took about 3 mins to 6psi and just kinda lingered there for a while. It's not easy to do but the point is it's possible. My next goal is 30psi After motor break in and Dodge modding my BOV. A boost leak test is one of most pita but important regular maintenace task, the key is patience and endurance, have fun.

 

[hun6over]

Are you talking about this? http://www.walmart.com/catalog/product.do?product_id=3992

 

[oldman]

Are you talking about this? http://www.walmart.com/catalog/product.do?product_id=3992

No, those are too slow and noisy, you need one with a built in storage tank like these. http://www.aircompressorsdirect.com/catalog/default.php?cPath=3_180_26

 

[hun6over]

Ok, cool. Ill check into those. Im not sure what shaft play is, but my turbo does have a wierd symptom. Whenever i drive my car when the engine is generally cool or has been resting for a few hours, i hear a loud ZIIIIIng sound somewhat like a "turkey call". THis sound happens when i start to boost and when i am medium or heavy on the throttle. This sound occurs for a few miles of driving from when i first start the engine when cooled or resting. After a few miles, i cant hear the turkey call noise anymore and it remains that way until the next time i drive the car when cooled.

 

[oldman]

Ok, cool. Ill check into those. Im not sure what shaft play is, but my turbo does have a wierd symptom. Whenever i drive my car when the engine is generally cool or has been resting for a few hours, i hear a loud ZIIIIIng sound somewhat like a "turkey call". THis sound happens when i start to boost and when i am medium or heavy on the throttle. This sound occurs for a few miles of driving from when i first start the engine when cooled or resting. After a few miles, i cant hear the turkey call noise anymore and it remains that way until the next time i drive the car when cooled.

Well first thing, never boost your car before it's fully warmed up. Shaft play is refering to the amount of side to side, in and out play of the turbo shaft, grab the tip of the compressor wheel and check for play. Lastly, turkey calls normally points to BOV, make sure that your MBC is not connected to the BOV line.

 

[hun6over]

I dont have a mbc hooked up yet and i am still running on my stock 2g bov until my evo 8 bov arrives in the mail.

Thanks for all the input guys. Especially you Oldman. Youve been very informative

 

[kmoore]

Thanks for all the input guys. Especially you Oldman. Youve been very informative

Like Always

 

[hun6over]

Hey, you guys were right about the pcv valve leaking. I did another boost leak test today except i did it from the TB elbow this time. The pcv was leaking bad, so i went to Kragen and got a replacement pcv valve (Fram FV266). I installed the new one and it leaked too! As a matter of fact, it leaks worse than the original one This is like

 

[oldman]

Never ever use anything other than an OEM PCV valve.

 

[hun6over]

ok hehe.. Do you know where i can get an OEM replacement online? I found a website that claims to sell "Genuine OEM Mitsubishi" stuff but they use different names for stuff so i dont know which one is the PCV valve. https://www.mitsubishiparts.com/oe_parts_catalog.html Here is the list of items they have under Emissions.

Emission system
Check valve
Egr tube
Egr valve
Hose
Purge valve
Solenoid valve
Valve
Vapor canister
Vapor hose

 

[kenamond]

ok hehe.. Do you know where i can get an OEM replacement online? I found a website that claims to sell "Genuine OEM Mitsubishi" stuff but they use different names for stuff so i dont know which one is the PCV valve. https://www.mitsubishiparts.com/oe_parts_catalog.html Here is the list of items they have under Emissions.

Emission system
Check valve
Egr tube
Egr valve
Hose
Purge valve
Solenoid valve
Valve
Vapor canister
Vapor hose

This one.

https://www.trademotion.com/partloc...5&make=24&model=Eclipse&year=1997&catalogid=1

And you can get a portable compressed air tank for cheap and fill it up at a gas station. I have an 11 gallon model, pressurize to 110psi, and it lasts me for several months. Compressor is nicer to have, though.

Don't be suprised if you have in/out shaft play. The turkey call sound reminds me of what my turbo did just before the turbo thrust bearing grenaded and broke the shaft. If you have in/out shaft play, start planning for a turbo replacement or rebuild. Side/side play is normal as long as the fins don't touch the housing. When it goes, pull over immediately, as you'll probably be pumping quarts of oil into your intercooler.

Good luck!

 

[hun6over]

Ok thanks. I just bought some pcv valves from the website that Kenamond suggested. I bought 2 of them (just in case since shipping costs 10 bucks no matter what) for 20 bucks shipped. Pretty good deal IMO. I just hope they work.

 

[oldman]

You could have waited till tomorrow and pick them up from the dealer, probably cheaper due to shipping cost.

Here is another good read for you. http://www.dsmtuners.com/forums/showthread.php?t=229338

 

[hun6over]

Yea probably . I dont know of any mitsubishi dealer around my area because the one that was here closed down a few months ago. Gas here in cali is expensive right now too so i figured im saving gas money

That link you just gave me is starting to make me worried that i just wasted money on the pcv valves . If you think so too, just say the word and ill probably cancel the orders since it isnt too late to do so. But... i dont know if i could make a setup like that since California emission is strict.

 

[oldman]

That link you just gave me is starting to make me worried that i just wasted money on the pcv valves . If you think so too, just say the word and ill probably cancel the orders since it isnt too late to do so. But... i dont know if i could make a setup like that since California emission is strict.

No you didn't, if you read the thread carefully, PCV valve is still an important part of the setup. As for California emmisions, the new setup is actually cleaner because you're using a catch can while still re-routing back to the intake manifold. VC > PCV > inlined sealed catch > heavy duty check valve > intake manifold. The addition of the heavy duty check valve is to prevent pressure leak through the PCV valve into the crank case when you're under boost. With that said, restore it to stock form before inspection so you don't have to explain to them exactly how the setup is suppose to work.

 

[kenamond]

Yea probably . I dont know of any mitsubishi dealer around my area because the one that was here closed down a few months ago. Gas here in cali is expensive right now too so i figured im saving gas money

That link you just gave me is starting to make me worried that i just wasted money on the pcv valves . If you think so too, just say the word and ill probably cancel the orders since it isnt too late to do so. But... i dont know if i could make a setup like that since California emission is strict.

I don't live in Cali, but I'd argue with anyone that a check valve setup just guarantees that the car will function at the factory air:fuel ratio even if the PCV valve starts to leak. A leaky PCV hurts fuel economy and emissions, and that's what those emissions nazis are trying to address. They could argue that you would fail your next emissions test if it were failed, and you'd then have to replace the PCV, but you could fire back with, "But I'd be adding polutants unnecessarily and unknowingly until my emissions test identified the problem. By adding the check valve, I'm doing my part to improve the lives of our children." And then you could toss in, "And the stock part is made overseas, I believe, so I'd be harming the economy - albeit slightly - every time the PCV failed by sending US dollars overseas!" And to bring it all together, "Honestly, the only reason I'm doing this is so that I can safeguard the environment!"

 

[hun6over]

By adding the check valve, I'm doing my part to improve the lives of our children." And then you could toss in, "And the stock part is made overseas, I believe, so I'd be harming the economy - albeit slightly - every time the PCV failed by sending US dollars overseas!" And to bring it all together, "Honestly, the only reason I'm doing this is so that I can safeguard the environment!"

HAHAHA!

anyways.. yea.. . So all i really need is to add a checkvalve and that would stop the pcv valve leaks? So i guess the catchcan isnt really necessary but is a bonus. Im trying to save as much money as i can

Thanks for the help guys