I'm shocked, do I have compressor surge turbo damage?

[Falcon55]

Wazzup peeps? My first post here, this must be the best DSM enthusiast forum on the internet in my opinion, the rest are fakes. Back on topic, I hope it's not what I think it is, one of my greatest fears. Sorry for the long story.

Me and a friend (well friend of my friend), were trying to find out why my 97 GST would "buck" at around 5,000 RPM and why it would sometimes shut off while driving, after dropping down to 1,000 RPM idle (I knew how to fix that). Since the beginning, my older bro always told me it was the speed sensor causing the "buck" since the speedometer would "shift" around irregularly when driving. He's very wise about cars and I ignored him, big mistake.

So one night, me and my friend researched on DSMTuners, concluded that the bucking was probably a boost leak (maybe even spark plugs) and decided the next morning we have to work on the car. Next day, we go to the dealership, buy the gasket covers for the throttle body and install them. The shut off would still happen, but not often. Almost fixed. Afterwards, we work on the car again. He convinced me that I had a boost leak coming from my BOV when idle. We felt small gusts of air coming from the BOV with our palms. So he started to tighten the BOV until he thought the "leak" ceased. Now that I think of it, it's the stupidest thing I let someone do to to my car. I test drove the car and heard fluttering noises at low RPMs (below 3,000). At high RPMs, the usual spurting sound of excess air from the BOV would be heard. I didn't know what the flutter was, but recently I found out it's a term called compressor surge.

Believe it or not tho, the shut off idle problem has ceased afterwards, , I have no clue why.

Well to make a long story short, I drove it with the BOV tightened since Friday, Feb. 22 until March 2nd, Sunday. 9 days, but since I haven't drove my car 2 days of the 9 days, so far were looking at my car running with compressor surge for about 7 days give or take. That sunday night (mar. 2), outside with highschool friends (c/o 06 REPRESENT! ), my older bro noticed my car not sounding right. We popped the hood, first thing my bro noticed was the BOV. He yelled "WHAT THE F***? WHO DID THAT!?" I told him as he loosened up the BOV. He said again "It's the speed sensor that causes buck, not the BOV! Never let that friend touch your car, it may have ****ed up the turbo." I'm then shocked, so afterwards I unplug the speed sensor, test drive and guess what?

My older bro was right, it wasn't bucking, I could it take to any RPM while driving. He knew the speedometer would "Balloon" all the way to around 130MPH, hit the governer and cause the buck, while in reality I'm pushing the car hard at 30MPH. Why? Loose speed sensor that needed to be plugged in harder, easy fix.

So now i'm worried as hell since my turbo sounds just a bit wierd (not too noticable), also I don't know if it's me or if my GST isn't pulling like it used to. Not to mention that I now hear a slight "clacking" noise at about 2.5 RPM (stationary) from inside my intake manifold (cylinder above engine), IDK why. Wierdest thing is my car doesn't shut off anymore... My fear, I just hope that a week of driving with compressor surge didn't mess up my turbo. HELP! Greatly appreciated, anything would help!

As for myself, I lurked these forums sometimes before registering, but I finally decided to make an account.

 

[90GSTBoosted]

I think you have the wrong definition of what compressor surge is. Do some searching.

 

[kenamond]

If the BOV wasn't releasing correctly, the flutter was probably compressor surge. If you read about it, you probably know that it increases load on the thrust bearing which can decrease the life of the turbo. But there's a way to check this.

Pull the intake pipe off of the compressor inlet, reach in and grab the nut on the center of the compressor wheel and check shaft play. You want *no* in/out play. Side-side will be there even brand new, but it will be small. It can't be so bad that it hits the compressor housing. Also, spin the wheel and see if it spins freely.

Then while the intake pipe is off, do a boost leak test. Should hold 20psi and leak down 1psi every few seconds if you fixed all of the leaks. Seach on this, as it's covered thousands of times.

You can test the BOV with a vaccuum pump attached to the nipple whose line normally goes to the intake manifold. I don't recall the exact vaccuum that should cause it to open, but it's in the Haynes manual.

If you have an aftermarket boost controller, don't tee into the BOV vaccuum line or it can interfere with the vaccuum signal from the intake manifold which can impact proper BOV function.

EDIT: Fill out your vehicle profile. You obviously have an aftermarket BOV, but we need to know what else you have to effectively diagnose problems, make recommendations, etc. Welcome aboard!

 

[VETTE_50_TH]

Well, you could have surged. If he overly tightened the BOV, im guessing you have an aftermarket, it might have surged. What was happening was the bov wasn't opening at lower rpm like it should, and causing a lot of that air to come back and hit the turbo.

[/QUOTE] When a compressor stall leads to a complete reversal of flow direction and loss of compression through the entire engine, it is also known as a compressor surge (although definitions differ, and often the terms are used interchangeably).[/QUOTE]

Take the intake off and check the in and out and up and down motion of the inducer.

James

 

[VETTE_50_TH]

kenamond you are a quick puppy you SOB. Stop reading my mind.

James

 

[cruisintalonawd]

Search "wow this sucks". The thread was started by iwannagofast89 and he had compressor surge with a 1g crushed bov at low boost and the compressor wheel nut came off. Make sure that didn't happen to you. what psi are you running

 

[Falcon55]

^I'm running 11 PSI of boost.

Damn, thanx, I appreciate the help. I will soon give rep points or however yall give eachother up's when helping out. I really can't fill out my vehicle info right now because i'm in a hurry, but it's all basically stock. Only thing I did was follow the proper Tee'd off configuration in the vacuum diagram (Tee off the vacuum line from the wastegate actuator, to the solenoid, to the turbo). My BOV is some no name japanese blow off valve, it looks wierd, it came from my older bro's friends 3000 GT front clip from japan. I'll see if I can get a pic of it later. Also I will definitely check the turbo out ASAP. I just hope it's not as bad as I think.



Thanx for the welcome aswell.

 

[kenamond]

Search wow this sucks the thread was started by iwannagofast89 and he had compressor surge with a 1g crushed bov and the wheel nut came off. Make sure that didn't happen to you. what psi are you running

Dude. It took me about 5 re-reads of that to understand that he should search for the "wow this sucks" thread. Then I read that thread and realized that you meant the compressor wheel nut, not the wheel wheel nut. I was wondering, "How the hell would compressor surge loosen that 22mm bastard that nobody can crack loose even with a 4-foot breaker bar?"

Anyway, I hope Falcon's turbo didn't grenade like that.

^I'm running 11 PSI of boost.

Damn, thanx, I appreciate the help. I will soon give rep points or however yall give eachother up's when helping out. I really can't fill out my vehicle info right now because i'm in a hurry, but it's all basically stock. Only thing I did was follow the proper Tee'd off configuration in the vacuum diagram (Tee off the vacuum line from the wastegate actuator, to the solenoid, to the turbo). My BOV is some no name japanese blow off valve, it looks wierd, it came from my older bro's friends 3000 GT front clip from japan. I'll see if I can get a pic of it later. Also I will definitely check the turbo out ASAP. I just hope it's not as bad as I think.

Is that BOV recirculated back into the intake pipe? I'd highly recommend getting a 1g BOV and an 2g/1g flange adapter. The 1g BOV can be had from eBay or the classifieds on this forum for around $20, and the adapter is $25. I think ExtremePSI and other vendors sell them. Or you could do a bit of upgrading including a upper intercooler pipe flanged for a Greddy or 1g BOV and save $25 on the adapter that you'd no longer need with the correct UICP flange. If you already have an upgraded UICP and it's flanged for a Greddy or 1g BOV, still go get the 1g BOV. If the UICP is flanged for Greddy, they sell adapters to 1g. The 1g BOV holds 18-20psi before it pops open, but it can be crushed or "Dodge Garage" modified to hold higher boost if you ever need that.

If you do a boost leak test (BLT), you'll find out just how high the BOV will hold. Mine pops at about 21-22psi uncrushed/unmodded. Just don't go putting 50psi into the intake if that mystery BOV happens to hold that high...15-20psi BLT pressure is fine if you're running 11psi boost. And you really should do a BLT. Make the tester, do the test, fix the leaks. Can make a pretty noticeable difference in power. Search for more info...and don't forget to fill out your profile.

 

[95autogst]

If you were only running at 11psi and with the BOV too tight for a week I don't think that it would have killed a turbo that wasn't already almost dead. Remember that blow off valves didn't even come on a lot of earlier turbo cars (the early 90's Pulsar GTi-R at 7-8psi comes to mined), not that the life of the turbo was helped by this lack of engineering...

 

[kenamond]

If you were only running at 11psi and with the BOV too tight for a week I don't think that it would have killed a turbo that wasn't already almost dead. Remember that blow off valves didn't even come on a lot of earlier turbo cars (the early 90's Pulsar GTi-R at 7-8psi comes to mined), not that the life of the turbo was helped by this lack of engineering...

It might be a coincidence, but back in the day of me not knowing anything about my car, the nipple on the 2g BOV broke off. I went a week or two with it broken while I tried to get a replacement (...shop told me I needed a new turbocharger system for $1800; they weren't DSM mechanics and didn't really know what they were looking for. That included everything from the turbo to the TB elbow including T25 and SMIC!).

Anyway, I sanded the broken pieces flat and epoxied it back together. A few months later, the T25 thrust bearing started letting go. A few days later, the smoke screen. Then I got my account here.

Could just be a coincidence, but that was with 78k on the T25 on a '97. If Falcon has similar mileage...

I think checking shaft play is probably still worth it so he can save the hassle of thrust bearking pieces in his oil pan and oil through the entire intake.

My $0.02.

 

[95autogst]

I think checking shaft play is probably still worth it so he can save the hassle of thrust bearking pieces in his oil pan and oil through the entire intake.

My $0.02.

Yeah without a doubt check for shaft play, as opposed to just guessing what the condition of the turbo is. I should have said that as well... good insight.

 

[Falcon55]

Dude. It took me about 5 re-reads of that to understand that he should search for the "wow this sucks" thread. Then I read that thread and realized that you meant the compressor wheel nut, not the wheel wheel nut. I was wondering, "How the hell would compressor surge loosen that 22mm bastard that nobody can crack loose even with a 4-foot breaker bar?"

Anyway, I hope Falcon's turbo didn't grenade like that.

HAHA, I thought I was the only one who thought that aswell. Same thing, except when I read it the first time, I was reading it a little quick and thought he typoed or something in the beginning, then thought his actual wheel came rolling off his car from compressor surge. I thought for a sec that it must have been the worst case scenario for compressor surge, . As I got back on later and actually took the time to read it (like 3 times) over, I understood what he meant about the turbine wheel and then searched "wow this sucks" thread, !

Is that BOV recirculated back into the intake pipe? I'd highly recommend getting a 1g BOV and an 2g/1g flange adapter. The 1g BOV can be had from eBay or the classifieds on this forum for around $20, and the adapter is $25. I think ExtremePSI and other vendors sell them. Or you could do a bit of upgrading including a upper intercooler pipe flanged for a Greddy or 1g BOV and save $25 on the adapter that you'd no longer need with the correct UICP flange. If you already have an upgraded UICP and it's flanged for a Greddy or 1g BOV, still go get the 1g BOV. If the UICP is flanged for Greddy, they sell adapters to 1g. The 1g BOV holds 18-20psi before it pops open, but it can be crushed or "Dodge Garage" modified to hold higher boost if you ever need that.

Well, my BOV doesn't recirculate back into my intake pipe. Nice advice tho, i'll go ahead and take your word for it since u were the first person to reach out and help me (u beat somebody to first post by a minute or so, ), also since I can tell u most definitely know what your talking about. I would have never knew 1G BOV's increase performance much better than 2G BOV's, I thought it was all about 2G BOV's for these 2G DSM cars.

If you do a boost leak test (BLT), you'll find out just how high the BOV will hold. Mine pops at about 21-22psi uncrushed/unmodded. Just don't go putting 50psi into the intake if that mystery BOV happens to hold that high...15-20psi BLT pressure is fine if you're running 11psi boost. And you really should do a BLT. Make the tester, do the test, fix the leaks. Can make a pretty noticeable difference in power. Search for more info...and don't forget to fill out your profile.

My older bro's friend has a BLT kit (good thing u told me the acronymn for Boost Leak Test, only thing that comes to my mind for BLT is Bacon Lettuce Tomato and i'm starting to feel a lil hungry ), i'll just go ahead and borrow it from him so I can use it. Oh and I filled out my profile information. Thx for reminding me!

If you were only running at 11psi and with the BOV too tight for a week I don't think that it would have killed a turbo that wasn't already almost dead. Remember that blow off valves didn't even come on a lot of earlier turbo cars (the early 90's Pulsar GTi-R at 7-8psi comes to mined), not that the life of the turbo was helped by this lack of engineering...

I hope your right and I will check shaft play tomorrow for sure.

Also kenamond, I like how u gave a lil story as to how u came about DSM tuners, I guess since i'm new u felt like it was time to explain your story how u came aboard long ago.

EDIT: I just found out you cant type the word u-r (but without the -), like you know, the word "you're" but in quick typing slang. Instead two ##'s came up.

 

[Black99gst]

this issue could also simply be "flutter" from the BOV... my type-s flutters a LOT! especially when i'm in very high vac (like 0-10 in/HG) .02

 

[kenamond]

If you still have the 2g BOV, put it back on. You need to recirculate or you'll run rich and stumble during shifts or when you let off the gas (that's when the BOV opens). And you need the BOV to open when you shift or you surge. The 2g BOV is good enough for stock boost and a helluva lot better than a surging, vented (non-recirculated), noname BOV. Read a bit about recirculating from the Newbie FAQ on this forum. Many want the nice BOV vent sound but don't realize that it impacts performance (car falls on its face when you shift).

If you BLT on the 2g BOV, it might pop at 12-13psi. But if you can hold 11psi without leaking down, that's a big step forward. Start thinking about upgrading some intake components. If you unbolt the stock filter box and look at the stock, plastic, unholy-mess UICP coming through the body underneath the airbox, you'll see why folks upgrade the UICP. Then you can get a good BOV and maybe start thinking about more aggressive power-adders.

 

[hypnoticpimp]

You need to recirculate or you'll run rich and stumble during shifts or when you let off the gas (that's when the BOV opens).

When im in any gear at around 3k and let go of the gas i can hear my bov leak...Thats normal right? Im having a hard time trying to figure out why my type rs bov flutters (maybe compressor surge) at low boost, (under 4psi)... but after reading i came to the conclusion that it's flutter rather than compressor surge...What do you think?

This fluttering sound you are getting a low boost levels seems to be common with this valve & isn't compressor surge. For some reason at the lower boost levels it just doen't seem to want to blow off in a solid burst.

This sold me...

 

[97gstnick]

Dude. It took me about 5 re-reads of that to understand that he should search for the "wow this sucks" thread. Then I read that thread and realized that you meant the compressor wheel nut, not the wheel wheel nut. I was wondering, "How the hell would compressor surge loosen that 22mm bastard that nobody can crack loose even with a 4-foot breaker bar?"

thats funny. i had to re-read his response 5 times as well. i was like wtf???

 

[kenamond]

When im in any gear at around 3k and let go of the gas i can hear my bov leak...Thats normal right?

Yes. When you let off the gas, the throttle plate closes, but the engine is still trying to draw air through the intake. Manifold pressure drops to -25inHg (if near sea level) as a result. That vaccuum activates the BOV.

Im having a hard time trying to figure out why my type rs bov flutters (maybe compressor surge) at low boost, (under 4psi)... but after reading i came to the conclusion that it's flutter rather than compressor surge...What do you think?

Don't know about the BOV flutter vs. surge. If it only does it at low boost and it is surge, it's lower pressure and won't beat up on the thrust bearing as badly. If it's just the BOV fluttering, but the air is still recirculating, it shouldn't be a problem.

I've never heard surge myself. I've read that it can sound like various things from bird chirpy noises to farts to fluttering sounds, but I read that on various other forums for other cars with other turbos and other intake designs. Not sure what it sounds like on our cars.

 

[Falcon55]

If you still have the 2g BOV, put it back on. You need to recirculate or you'll run rich and stumble during shifts or when you let off the gas (that's when the BOV opens). And you need the BOV to open when you shift or you surge. The 2g BOV is good enough for stock boost and a helluva lot better than a surging, vented (non-recirculated), noname BOV. Read a bit about recirculating from the Newbie FAQ on this forum. Many want the nice BOV vent sound but don't realize that it impacts performance (car falls on its face when you shift).

If you BLT on the 2g BOV, it might pop at 12-13psi. But if you can hold 11psi without leaking down, that's a big step forward. Start thinking about upgrading some intake components. If you unbolt the stock filter box and look at the stock, plastic, unholy-mess UICP coming through the body underneath the airbox, you'll see why folks upgrade the UICP. Then you can get a good BOV and maybe start thinking about more aggressive power-adders.

I wish I had a 2G BOV. Wait, I don't even know if I have a 2G BOV, like I said it's a mysterious no name japanese blow off valve. It can be a 1G, 2G, even a 0.5G for all I know =P. But yea, I put in my profile for parts I want, I need an air intake and new BOV ASAP before anything. Front mount intercooler would be nice too.

I was searching on google for something close to my BOV and oh snap, I actually came extremely close to what mine looks like. Exactly like in the pic except for the gold stuff (I think that's the little line to recirculate, mine doesn't have that) above on the top:

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In case if image doesn't work, here's the link: http://www.avoturboworld.com/avoshop/images/150_evo_bov.jpg

EDIT: Hey hypnoticpimp, I like your Black 98 GSX because it brings back memories of my 97 Black Eclipse RS, except that it didn't have fog lights and urs does. After I had my fun with the Black RS (I wasn't a fan of RST conversions, doesn't feel legit IMO), I sold it and bought a 97 White Eclipse GST, the one I own now. I like the 4G63 engine in the GST aswell, I got tired of the 420A quickly. But I remember hearing this once from someone in the Army, I saw him near his Honda S2000 (Recruiting station in Hialeah), then car talk came about. The RST conversion popped up in the conversation, and I wanted to know in his opinion which he would think is better performance wise and cheaper, a 97 RST (turbo conversion) or buying a 97 GST (comes stock with turbo). He said the GST already comes with turbo, but since the RS doesn't come with turbo, the 420A engine is a little stronger than the GST to account for the lack of turbo, even though overall (both stock), the RS itself is slower than the GST. But after the RST turbo conversion, the RST would infact be faster than the GST.

I always wanted to know if that was true. Is it?

 

[kenamond]

I just cruised the classifieds on this forum, searching for "BOV". Found several 1g uncrushed BOVs for $20 (that's a good price, btw). Also found a 2g BOV in the ad below with "best offer". Offer him $10+S&H. I'd mail you mine for shipping cost, but the nipple's broken off. You need a functioning, recirculated BOV.

Message - DSM Classifieds

If you don't have the recirculation tube (goes between the BOV and intake pipe), you'll need that no matter what BOV you choose. I'm sure you could find one dirt-cheap either in the classifieds or for a bit more money from DSM eStores like dsmparts, extermepsi, etc. Many folks spend $250 on some shiney BOV and vent it, and they'll have recirc tubes for sale (along with issues caused by venting).

 

[90talontsi90]

Your going to have to give him a few days before he can get in the classifieds, that whole 50 post things can take a little while, and teasing him with a good deal like that... tisk tisk

Kyle

 

[kenamond]

Your going to have to give him a few days before he can get in the classifieds, that whole 50 post things can take a little while, and teasing him with a good deal like that... tisk tisk

Kyle

Doh! I'm not clear on what new members can see, obviously.

There's always eBay. I got my 1g BOV for $25 shipped from eBay. Looked like butt. Sanded the surface corrosion off and got it all nice and shiney one afternoon sitting in the sun with a mug of Guinness while the kids played in the yard. Then painted it gloss black. Looks fantastic.

 

[cruisintalonawd]

Sorry guys I was a little tired but I edited it to make sence

 

[Falcon55]

Sorry I couldn't do this any earlier, since I was busy most of the morning/afternoon. So I had time around 5PM. But w/e, I picked up the Digi Cam, went to my car for 15 mins to do this quickly and snapped some shots while I was at it. I was a little shocked at how I found a little bit of oil coming from my turbo (unless if that's leaked oil from out of the intake that made it's way inside), but whichever way it happened, is that normal? Not only that, I had literally no "left or right" motion with the blades on the wheel (as in the direction to the housing walls around them), barely very very little in/out play (inwards towards the turbo and outwards towards the oil resedue). I spinned the blades and it was fine, they spinned freely, didn't touch compressor housing.

Well enough of that, here are the pics:

My engine, stock at it's finest (I took off my fusebox cover and notice the BOV, wtf is that?):

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Far view of turbo, notice the oil, why?

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Front view of turbo, pic may seem a lil jaggy but trust me, it was razor sharp (there was extremely minimal play, barely anything, going inwards and outwards for the blades in that view. Also there was no play from left to right, didn't touch housing and spun free, without a problem).

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Damn, relieved my blades didn't look like iwannagofast89's "wow this is sucks" thread, I was expecting them to look horrible:

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Another view of blades:

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Stock intake pipe, you can see the oil on the bottom front of the intake hole:

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View of turbo with no flash from camera:

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Up close view of BOV, I got it from my friend's 3000GT front clip, wtf !?

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Ok, so my car right now is out there, hood closed and the intake is with me. So what do yall think so far?

 

[kenamond]

Oil will get into the intake from the rubber hose that goes from the passenger side of the valve cover to the side of the intake pipe. Many folks will put a catchcan or in-line fuel filter on that hose to keep oil out of the intake pipe. That oil gets all over the inside of the intake tract and into the combustion chamber. Oil in the intercooler decreases its efficiency, and oil in the combustion chamber leaves deposits.

It's odd that you have no side-side shaft play but a small amount of in-out. I'd check on the shaft play every now and then to see if it gets worse.

Get a different BOV and recirculate it. Easiest and cheapest would be a 2g BOV and stock recirc tube. I imagine the intake pipe has a cap on the tube that would normally connect to the BOV? If not, it better; don't drive the car unless it's capped. Again, I'm talking about the tube on the part that you unclamped from the turbo to check shaft play.

 

[dsmconvict]

It looks like you could actually recirculate that bov. Loosen that clamp at the bottom and rotate it. Then go buy a new recirc tube and you should be good on the recirc end.