Boost Leak

[UCF201101]

Good evening everyone,
I am unsure to post this due to the unforseen problem. I have a quick question regarding my car. I had my car tuned on 13 psi. He said he left fuel for me to run up to 18 psi. The car ran great. I have megasquirt installed on it. The car would really pull hard. Two days ago my friend moved the line that runs from the turbo to the wastegate on the top port. The car boosted over 20 psi and a loud pop was created. The guy that tuned my car said that is the overboost protection. Over the course of a week it popped a few times (I never stomped on in it first or second). Well a few days ago I stomped on it in first and second and the car made the banging sound. What makes this time different was the car shut off. I got out of the car and checked the timing belt, oil leaks...etc. I cranked up the car and drove it for a few miles and then stomped on it. The car did not pull like it did. Its obviously something is wrong. I went home and performed a compression test. On all four pistons it showed 150. There were no water in the oil. I did a boost leak a few mins ago and nothing that really would cause a lost of power like that. I am stumped and need some ideas. The turbo has no shaft play. The ic piping is on tight. What could it be? Cracked rings, lands?

 

[glowryder]

That sucks. Hard to day. Did you pressurize the turbo inlet? How long did it take to leak down the PSI from the test? Check your blades, and make sure they arent trashed.

 

[bryanwheat]

The wastegate IS NOT supposed to have the boost source hooked to the top port. That will make the wastegate not open. It will make the turbo make maximum boost. Check the intercooler couplers you could of burst one or something like that. Tell your friend that he is not allowed to touch your car any more.

 

[UCF201101]

I already told my friend to never touch my car again . The fins on the turbo are good. I've noticed around the blow off valve it leaks. Is this suppose to happen? I noticed on the boost gauge that it takes longer to get to 10 psi. It hits full boost around 4400. How do I do a leak down on the cylinders? I dont want any cracked piston rings/lands. Thanks for everyones entry.

 

[GSTurbo1]

WASTEGATE LOCK UP!!! No bueno, you probably blew a throttle body seal. Open up your throttle body while you boost leak test. I would not run your car on 20psi unless it's built for it man.

 

[UCF201101]

I have the bottom end built for it. When I have the line on the bottom of the port it stops boosting at 10psi like it should. If its locked up what would happen? Would I have to loose a good amout of air for my car to take forever to spool completely up? When I hit 15psi it feels like 5 psi...

 

[Josh97eclipse]

Your wastegate sounds like its broken, the valve isnt opening all the way creating the desired boost. That pop you heard may had been a pop from the turbo, ripped ic coupler its really hard to say.

 

[GSTurbo1]

I have the bottom end built for it. When I have the line on the bottom of the port it stops boosting at 10psi like it should. If its locked up what would happen? Would I have to loose a good amout of air for my car to take forever to spool completely up? When I hit 15psi it feels like 5 psi...

man... you need compression check and leakdown check, boost leak... everything in the book to make sure you have not torn anything up in the bottom end or head.

 

[UCF201101]

I did the compression check. I have 150 psi across the motor. All the IC piping is on correct with no leaks. However, I do have small leaks from vacuum lines and blow off valve. I had a few minor leaks before so I dont think that it would cause the performance to decline that bad. I drove the car and kicked it in first and second and the megasquirt overbooost protection kicked in. The car shut off. I cranked it back up and boosted it and the power was not as the same. I will clamp those hoses down with silicone around then to ensure they are leak proof. Any other suggestions?

 

[91mits]

man... you need compression check and leakdown check, boost leak... everything in the book to make sure you have not torn anything up in the bottom end or head.

he just said, he was able to turn on the car and drive it home, it surely looks like a wastegate or intercooler piping issue, its not that easy to break these bottom ends,
OP when i was at 26psi, my clamps for the lower intercooler pipe couldnt handle it and popped off, sounded like a loud bang...look over ## piping again...


edit never mind, i thought your talking about the 4g63T motor.

 

[Josh97eclipse]

Post some pictures of the setup please, will help us better solve your issue, also take the wastegate off and see if the valve is working right. Make sure its not bent or snapped. Also check shaft play in the turbo (in/out and up/down)

 

[UCF201101]

Turbo has no shaft play in any direction. I got done checking the clamps to the innercooler those are good (no bubbles). I fixed the vacuum lines where they do not leak. However, the afpr does leak a tiny. If I tore the bottom in wouldn't I know or atleast hear a sound? Oil pressure looks good and I've put 200 miles on after all this that happend. I am hitting 16 psi but it takes forever. I've checked twice today with boost leaks. There is no leaks on the piping whatsoever. That loud bang was MEGASQUIRT stopping the car from overboosting. It was set at 20psi.

 

[GSTurbo1]

your wastegate is messed up, if you have internally gated your flapper may have cracked or melted. Something to do with your wastegate... fix it, i bet your running rich

if it spools but takes forever to spool there is something wrong with it... trust me. I have already been through this issue.

 

[VelocitàPaola]

Thread moved to appropriate forum.

 

[UCF201101]

If I am wot I am running high 10s low 11s. If my wastegate is messed up wouldn't it stop me from building boost or causing me to have to much boost? I hope that it is the wastegate because it has me stumped. I will take the wastegate off. What should I be looking for? I know there is a rubber gasket type in the middle. I have an EXTERNAL wastegate.

 

[Josh97eclipse]

You have not done what others suggested to do with the wastegate. Take the 2 bolts off and see if the valve is working. Never knew MS had a overboost protection.

 

[UCF201101]

I didnt either but it does. I will remove the wastegate when I get home from.work. Maybe someone can explain to me that if it was the wastegate wouldnt i see either the spring not working (making boost) or will allow the wastegate to open up. i have a ten psi spring and the car will not go past the ten psi mark...

 

[GSTurbo1]

look for a tear on your diaphragm

 

[UCF201101]

I just finished pulling the wastegate off and there is no tear in the diaphram.

 

[UCF201101]

Any other ideas?

 

[Josh97eclipse]

Dont look at the diaphragm, if that was torn you would spike boost. As we asked post pics please. Now go look at the valve on the wastegate and see if thats broken.

 

[LeeSD1]

Sounds like the wastegate. Use some compressed air and set it at the psi rating of the spring and blow it into the WG, see if the valve is fully opening and closing completely and normally and making a seal.

 

[UCF201101]

I will be doing the test tomorrow LeeSD1. I thank you for your response. I am puzzled at this problem. I can usually figure it out but I don't know what will cause something to instantly stop performance wise. I will post results tomorrow...Btw I did another boost test and there are no leaks (intake and exhaust as well). I will pull off the waste gate after the compressed air test. Thanks everyone.

 

[UCF201101]

So I checked the wastegate, blow off valve and did several boost leak test. I did find out that around the turbo housing it was leaking all around it. The picture below shows only one side but if you spray soapy water around it will instantly form bubbles. Will this cause my car to run poorly? Also, what will cause this area to leak? Can I have my turbonetics turbo rebuilt?

 

[Josh97eclipse]

This will cause a boost leak. Take the compressor cover off and see how that o ring looks.