My 14b compressor seal (o-ring) is leaking! Where do i get a new one??

[mhuffman]

I have 91 GST with 3" DP, 2.5" cat, 2.5" muffler, no free mods, stock MAS. I have new 0.028" NGK's and accel wires. The car runs really well and gets 25+ mpg. It also runs smoothly to 6000rpm+ when not full boost.

However, at around 5000+ rpm's and only at full boost i am getting complete fuel cut (AKA brick wall). I idle smoothly at 19 inHg and the turbo spools very well (14b). My dad followed me and under full boost i do NOT blow out any black smoke (AKA not running rich). I do not feel boost spike before i get fuel cut, just a smooth pull and them WHAM. Otherwise, the car runs very strong. I have no reason to think i have any boost leaks or a malfunctioning wastegate.

Thanks.... DSM's are a PITA!! But they're so fun!

UPDATE: I did a pressure test... i'm getting a major leak from the turbo. I suspect it's the compressor seal. I can feel and hear major air leaking from the compressor, the system only holds air for 5 seconds if i go to 10psi, the leak is that big. I guess i pinpointed the cause of my fuel cut.

I called a local dealer and they said they have 4 in stock for $5 each, so ill put one on and post if it fixed the problem or not. Thanks again with the help everyone.

UPDATE 2: I fixed it! Hey everyone, i replaced the seal and no fuel cut, it pulls much smoother and driveability feels better. The old seal was flat, hard, and cracking and disintegrated upon taking it out. It took a few hours but it was well worth it. If anyone's interested in a How-To i could make one. I replaced the seal with the ex. manifold and turbo housing still on the car, i just removed the center section and compressor cover. Seals are only $5 at any local Mitsubishi dealer. It's just the labor and the special tools.

 

[KBasham03]

are you running stock boost..?

 

[bastarddsm]

I had a freind with a 92 tis awd that did the same exact thing....had fuel cut at 9 psi...Ended up being the ecu caps were bad.

 

[mhuffman]

are you running stock boost..?

Yes i am running stock boost, even the BCS restrictor is in place.

 

[DGajre777]

Do a boost leak test.

 

[mhuffman]

Do a boost leak test.

I made a boost leak tester but if my idle is good, my idle vacuum is good, and im not blowing any black smoke, i dont see how i'd have any major boost leak.... can a small leak really cause fuel cut? i thought you really need to flow some air past the MAS for that to happen?

 

[DGajre777]

I made a boost leak tester but if my idle is good, my idle vacuum is good, and im not blowing any black smoke, i dont see how i'd have any major boost leak.... can a small leak really cause fuel cut? i thought you really need to flow some air past the MAS for that to happen?

Yes, any boost leak can cause fuel cut. During a boost leak, you are losing metered air, which is the cause of fuel cut. Check your couplers, the blow off valve and throttle body for boost leaks too. Do a boost leak test and rule it out and then you can focus on other problems.

As for your ticking noise in your ECU that happened to me on my 92 Eclipse before the ECU died. While you are at it, take it out and see if your capacitors are leaking. Check the vfaq, there's a thread on it.

 

[mhuffman]

Yes, any boost leak can cause fuel cut. During a boost leak, you are losing metered air, which is the cause of fuel cut. Check your couplers, the blow off valve and throttle body for boost leaks too. Do a boost leak test and rule it out and then you can focus on other problems.

As for your ticking noise in your ECU that happened to me on my 92 Eclipse before the ECU died. While you are at it, take it out and see if your capacitors are leaking. Check the vfaq, there's a thread on it.

How can i tell if the BOV is functioning properly?

 

[DGajre777]

How can i tell if the BOV is functioning properly?

I didn't mean check it to see if it is working properly, I meant check it for boost leaks at the flange/gasket.

 

[xveganxcowboyx]

I had signifigant boost leaks and no black smoke.

Start with running the test. If it doesn't hold 20 psi well (drops rapidly) start checking for leaks where DGajre777 said. Also I recomend checking where your injectors meet your head. A spray bottle of soapy water will do wonders. If you BOV is leaking you'll probably be able to hear or feel the leak. Failing that you can always cap the end and see if your results change.

 

[mhuffman]

I did the pressure check.... i'm getting a major leak from the turbo. I suspect it's the compressor seal. I can feel and hear major air leaking from the compressor, the system only holds air for 5 seconds if i go to 10psi, the leak is that big. I guess i pinpointed the cause of my fuel cut.

It's a 14b... how easy is it to replace the compressor seal?

 

[mhuffman]

Hey everyone, i replaced the seal and no fuel cut, it pulls much smoother and driveability feels better. The old seal was flat, hard, and cracking and disintegrated upon taking it out. It took a few hours but it was well worth it. If anyone's interested in a How-To i could make one. I replaced the seal with the ex. manifold and turbo housing still on the car, i just removed the center section and compressor cover.