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Discussion Starter · #1 ·
So i replaced my head gasket this weekend. It was kinda fun. Had a nice crack in the gasket around cylinder number one. Well everything went back in place after many hours and now my car run great in that is doesn't eat coolant or start up rough. but now i have a question about the turbo. So i decided to have some fun for once and use that turbo a good amount. After using it a couple times it didn't want to go past the middle part of the orange. And i didn't notice any wierd noises. just didn't want to spool up. So when i get back and let it idle for a couple min i just rev the engine up to around 2000 rpm and as the engine come back down to idle i hear a metal noise. Its like something is a little loose of something... i only hear this when i use the turbo.. any ideas... should i try and record it?
 

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Discussion Starter · #2 ·
I guess no one knows this but ill explain it better and maybe someone will know. So when i WOT my car in second and third gear i get the beautiful torque steer and rush that i have always got and the turbo gauge goes just barely into the red and its smooth. then i drive normal for a while and if i do the WOT again the turbo gauge goes into the middle of the yellow but thats all and it feels like its holding my car back. So i go back and let it idle and, when i do a quick rev up to 2000 rpms, on the way back down to idle i hear a rattling noise. I only hear this after using my turbo hard on a drive. I have no idea where to start looking.. Any suggestions?
 

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Have you done the turbo vacuum line bolt mod in the sticky? You might be loosing the boost from the EVAP system. Find the sticky about restoring lost boost. Sounds like something might not be hooked up after putting the vacuum lines back on. I'd re-check the hoses and do the mod in the sticky and check for vacuum leaks and sucking air sounds.
 

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Discussion Starter · #4 ·
Have you done the turbo vacuum line bolt mod in the sticky? You might be loosing the boost from the EVAP system. Find the sticky about restoring lost boost. Sounds like something might not be hooked up after putting the vacuum lines back on. I'd re-check the hoses and do the mod in the sticky and check for vacuum leaks and sucking air sounds.
Nathanthepilot

I checked all my hoses and used diagrams to make sure they are set up right and they are fortunately. I have not don the sticky thing and closed the top part of the boot control valve, but yesterday while in second gear i decided to spool up the turbo and when it went into the red i hear a whistling noise...

And my next question is how can someone tell in the wastegate is bad?
 

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Nathanthepilot

I checked all my hoses and used diagrams to make sure they are set up right and they are fortunately. I have not don the sticky thing and closed the top part of the boot control valve, but yesterday while in second gear i decided to spool up the turbo and when it went into the red i hear a whistling noise...

And my next question is how can someone tell in the wastegate is bad?
I check the basic mechanical action of the wastegate by using a hand pump and pressure gauge to pump the line to the wastegate.

I put my hand on the wastegate actuator rod so I can feel it move as I pump it up. I note the pressure, then keep pumping until it is wide open, and note the pressure.

What happens if you take the wastegate pipe off!!
BE CAREFUL if you do this this will give max boost, and you can hit the fuel cut. Only do this once, you don't want to damage the engine.

Also, using a good quality auxilary boost guage with accurate figures will give you real data compared with the in car boost/vac gauge
 

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Rawill,

Could this be a bad Boost Control Valve? What kind of whistling is it?
 

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yes it could be, T7 valves are known for coming apart. Norman Lovie on the 9000 site often pulls them apart and glues them together. Even from new.

A whistling could definitely be an air leak.
 

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Discussion Starter · #8 ·
I didn't replace the TBV yet. It whistles maybe in a blue moon. But i was driving yesterday on the high way and was going about 65 when i dropped it into forth and put my foot down all the way and my turbo went into the Red like more than halfway which i have never seen before and my car bucked very little. Then it would not let the turbo get past mid orange part of the turbo gauge. it felt like something was holding it back. So i get back to my place. let the car idle for a while and when i rev it up to 2000 rpms i can hear a rattling noise from the engine compartment as the engine travels back to idling rpm. any thoughts? can this be a boost control valve problem? waste gate? Boost control valve?
 

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Hi, I was just looking at what WIS had to say. If your waste gate control arm is loose, or the clip that holds it on is loose, it can cause a rattling noise and is accompanied by code 1105. I'd take the heat shield off and have a good look see at the turbo for something amiss. Check for loose or broken vacuum lines in the turbo area also... for that matter all of the vacuum lines... Let us know what you find. Hopefully your turbo isn't going bad.
 

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Discussion Starter · #10 ·
Hey Nathan i just checked and the rod is on the connected to the waste gate level and isn't loose... Could this is a boost control valve problem?
 

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Does the waste gate rod go back if you try to manipulate it by hand? How about the vacuum lines? All there and connected? If you haven't replaced them, I'd try doing that first. Shouldn't cost much for about 10-11' of vacuum line. If you replace, get the good silicone ones. There was a thread on here somewhere about doing it... I found mine on eBay, but I think Eeuroparts sells it too. Mine were silicone and thicker than stock.
 

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Discussion Starter · #12 ·
Ok i Checked the lines and they all seemed connected. I wil check to see if i can move the waste gate by hand in a few hours cause the engine is a little two hot right now. Should i be able to move it easily or with lots of effort?
 

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I didn't replace the TBV yet. It whistles maybe in a blue moon. I can hear a rattling noise from the engine compartment as the engine travels back to idling rpm. any thoughts? can this be a boost control valve problem? waste gate? Boost control valve?
TBV ( I guess is APC/BPC valve) the one with 3 hoses coming out of it.
They are cheap, I just bought 2 T7 valves for my 9000's.

Try your car on base boost only and see if it performs properly, no rattles or whistles. Just connect the compressor pipe to the wastegate pipe. If that eliminates your issues then it is likely to be the TBV valve.

According to others they do rattle, ( haven't fitted mine yet - I have another issue to resolve first).

As for Wastegate working, use a hand pump and an air pressure gauge, connect to the wastegate and pump up with one hand, put your other hand on the actuator rod and note the pressure it begins to move, this is the base boost pressure. Keep pumping and see at what pressure it is wide open.

Did you check the turbo for end play when you had the head off.
Was it nice and snug with no movement.

The other check you can do MUST BE DONE WITH CARE.

Remove the pipe to the wastegate, this means the car will get FULL BOOST, and can reach the fuel cut if you floor it too hard.

Drive it carefully and increase the throttle noting what the boost gauge shows. Once you know you have full boost back off.
It is best with these checks not to rely on the in car gauge, an accurate aux boost gauge will give you accurate figures.
 

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The wastegate rod should more with a little bit of effort. Maybe 20-30# of force or so. I know there is a way to measure the force required to open it exactly, but I think it takes some special equipment.

You did the turbo bypass "bolt" mod, right? It's in the sticky for 9-5 workshop. That will eliminate that possibility. Basically you cap the top vacuum line going to the Boot Control Valve.

Anyone else have some ideas on what this is making the noise and limiting boost?
 

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Discussion Starter · #15 ·
Thanks Nathan. I went outside and tried to move the waste gate lever with just my hand. not tools. It didn't budge a bit. I checked the lines again and everything seems to be on perfectly. No i didn't not take out and plug the last line on the BCV. Should i do this? i was under the assumption that you would need to do that if you weren't getting enough boost. Im getting lots of boost for the first two spool ups ( i think to much, sometimes in the middle of the red) and then it won't let me get past the middle of the orange the next times.
 

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Doesn't sound like a bolt-fix issue to me... However, perhaps you caught it early as one of the check valves is starting to fail. Still, I would think that it would just leak less boost, not leak no boost one time and then leak a lot the next.

Did this only start happening after you did the head gasket?

Sounds to me like your car is protecting it's self. If you went half way into red, that usually is a sign that something is wrong. However, I find it interesting that there wouldn't be a CEL for a potentially damaging event.

What's equally interesting is that the car seems to be capable of controlling the wastegate still, as it then seems to limit it after you go into the red. From what I've found, the "turbo" gauge has to have something to do with the MAF, as I've had leaks after the turbo and the gauge will go all the way up, while my boost gauge will not (Turbo is pulling correct amount of air... But it's not getting to the manifold w/ proper pressure because of the leak). Therefore, if my theory is right, the turbo gauge is a good sign of whether or not your wastegate is working.

Would you say this seems to be heat related? Does the car operate fine for a period of time then develop this problem? Or is it literally one good pull and then it's limited?
 

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Well, this is an interesting quote from Eeuroparts:

Name: APC Boost Control Valve (BPC valve)
Part Code: 7485576
Brand: Genuine Saab
Description: APC boost control valve for any 2.3L turbo 90-98 9000, 2.0L turbo NG 900 94-98, and 99 9-3 models (not Viggen). This is the most common cause of underboost(needle won't go past middle yellow), and overboost(fuel pump cuts out when needle goes 2/3 into the red).



I highlighted the text of interest in green. I have an extra BCV 02Aero. If you're interested in buying it and giving it a shot to see if it makes a difference, PM me and we'll figure something out.

Have you tried to put the compressor line up to the wastegae line like Rawill mentioned? Sounds like an easy check. I had a look at my waste gate earlier and it WILL move to the right with 2 hands pulling it with a little leverage on the manifold. It sounds like your WG is working though, so maybe it is the BCV.

Nathan
 

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Discussion Starter · #19 ·
Doesn't sound like a bolt-fix issue to me... However, perhaps you caught it early as one of the check valves is starting to fail. Still, I would think that it would just leak less boost, not leak no boost one time and then leak a lot the next.

Did this only start happening after you did the head gasket?

Sounds to me like your car is protecting it's self. If you went half way into red, that usually is a sign that something is wrong. However, I find it interesting that there wouldn't be a CEL for a potentially damaging event.

What's equally interesting is that the car seems to be capable of controlling the wastegate still, as it then seems to limit it after you go into the red. From what I've found, the "turbo" gauge has to have something to do with the MAF, as I've had leaks after the turbo and the gauge will go all the way up, while my boost gauge will not (Turbo is pulling correct amount of air... But it's not getting to the manifold w/ proper pressure because of the leak). Therefore, if my theory is right, the turbo gauge is a good sign of whether or not your wastegate is working.

Would you say this seems to be heat related? Does the car operate fine for a period of time then develop this problem? Or is it literally one good pull and then it's limited?
No this started sometime over the winter. It don't quite know if it happens when the engine is cold of not because i don't run my engine hard until its up to temp for a couple minutes. I usually get about two good pulls then it starts acting up. What tool do i need to use to test my Waste gate?
 

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Discussion Starter · #20 ·
Well, this is an interesting quote from Eeuroparts:

Name: APC Boost Control Valve (BPC valve)
Part Code: 7485576
Brand: Genuine Saab
Description: APC boost control valve for any 2.3L turbo 90-98 9000, 2.0L turbo NG 900 94-98, and 99 9-3 models (not Viggen). This is the most common cause of underboost(needle won't go past middle yellow), and overboost(fuel pump cuts out when needle goes 2/3 into the red).



I highlighted the text of interest in green. I have an extra BCV 02Aero. If you're interested in buying it and giving it a shot to see if it makes a difference, PM me and we'll figure something out.

Have you tried to put the compressor line up to the wastegae line like Rawill mentioned? Sounds like an easy check. I had a look at my waste gate earlier and it WILL move to the right with 2 hands pulling it with a little leverage on the manifold. It sounds like your WG is working though, so maybe it is the BCV.

Nathan

I am going to try the compressor thing first... I just have to read about how to do this. If that checks then i think my next move should be to get the boost control valve. Is the one you have new?
 
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