Boost Leaks

Revmoto

Member
Alright everyone I have been battling an issue where my brothers car won't see past 0psi. I boost leak tested the car and after fixing a bunch of leaks including a major leak on the cold pipe I still can't seem to build boost. The car is also leaking from the throttle body seals pretty bad and from each injector. The rubber parts seem to have lasted awhile given the car has 93k miles on the clock. Throttle body seals are a problem with Evo's so I was familiar with this issue and how to spot it but is this a common problem for you guys? I do not see any aftermarket seals to replace these so I guess I will have to go with OEM. Injectors I will replacing OEM also. I know on my evo the car still makes boost even with a major leak. I know boost is more than double but it still showed signs of life. I am running wastegate duty but unsure if those leaks could justify such a loss.

As of today I am 100% the turbo is still alive. It spins freely without noise. I revved the car in idle with the intake and cold pipe off and felt air rushing out of the compressor so I know it is working. The car at the moment just feels extremely sluggish and slow. While boost leak testing the car I found that my gauge only read 6psi when my compressor was charging the system to 10psi. I am not too worried as mechanical gauges are always off. The good news about it though is that it showed me it is building pressure. I blew through the hose but struggled which ensures me it is leak free from gauge to firewall. Vacuum is at -22 which seems normal for these cars.

Any problematic parts on these cars that are normally the cause? Anybody with similar issues?
 
what car is this on? an evo? the wastegate flap on the turbo is probably stuck open. i had the same issue, that was my problem.
 
No I drive an Evo but am using a lot of the same methods on my brothers 2003 Mazdaspeed Protege to bring life back to his car. The flapper is working as I checked that when I replaced the wastegate with an ATP unit. As stated the turbo blows air for sure and should easily see wastegate pressure.
 
Check the exhaust manifold for cracks and leaks. If the manifold is cracked or you have enough exhaust leaks, you will not spin the turbo enough to build pressure. You can also build 6psi, but not flow enough air due to leaks. Good luck.
 
Normally if the turbo manifold is cracked I will have a bad exhaust leak and a bad idle. The car is idling great and is tick free which will rule that out. No guess the parts that are faulty as I basically went over the entire car and found the major issues. I am just curious who has seen these leaks and if it drastically decreased your boost pressure like on this car. Also I am having a hard time sourcing the parts needed to fix the issue. I am in need of throttle body shaft seals and injector o-rings. Do you guys have a go to member on here for oem parts? I really hate dealing with the people at my local mazda dealership as they may be the dumbest people I have ever encountered.
 
i had this same problem and to be honest, i changed my wastegate actuator with the ATP one and it was fixed. And after that, a boost problem i had was that my actuator wasn't getting the vacuum, yet my vacuum was reading normal.
 
i had this same problem and to be honest, i changed my wastegate actuator with the ATP one and it was fixed. And after that, a boost problem i had was that my actuator wasn't getting the vacuum, yet my vacuum was reading normal.

As stated this is a brand new ATP unit. Vacuum shouldn't have anything to do with the operation of your wastegate since it requires only boost to function properly. The flapper felt fine when the wastegate was being replaced so I know that isn't stuck open. Tonight I took off the egr valve and gave it a good cleaning which allowed me to build 1psi. I am going to do another boost leak test once the injector seals come in and see if the IAC is still leaking. The car at the moment is ungodly slow. I doubt it is even making 100whp.
 
Wastegate actuators can fail at either way. They can not allow you to build boost, and have you over boost, just saying
 
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