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Discussion Starter · #1 ·
Ive been having a problem with my ABS and TCS lights since I bought the car, but now im having a completely different problem. I have a 1992 Saab 9000CD Turbo, If I accelerate into the 2000-4000 RPM range and then push the clutch in, 75% of the time the RPM'S will drop and then fail to catch at 1000 and the car will stall. The car has a manual 5-spd transmission so regainging the engine isnt that difficult EXCEPT most of the time its because of an upcoming stop sign or light, so stalling means turning the car off completely and restarting. What component keeps the engine running after high rpm's then clutch in? Im also getting a Check Oil Level light even though the engine oil level is fine, the light goes out after about 5 minutes of driving.
Any help is greatly appreciated,
Aaron Riesbeck
 

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two potential reasons
one is your AIC valve ..do a search on this (not had this prob but I believe you can clean it out )
or a sticky throttle flap which can be cleaned out nicely with some carb cleaner and some rag (be gentle with it !)It usually has a coating of gunge around the flap causing it to stick
hth
 

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Discussion Starter · #3 ·
Im coming across some things online about the turbo bypass valve causing the engine to stall on deceleration after a turbo situation, since the turbo usually becomes active under high rpms, and pushing in the clutch leads to a deceleration of the engine...could the bypass valve be the problem? Also, Im noticing the AIC valves for these cars run in upwards of $300 is that the normal price? Or am I getting ripped off?
Thanks again,
Aaron
 

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Check the bypass valve and hoses first, because they are easier to check and cheaper to fix (I had this symptom from a faulty bypass valve).

I think that price is around right for an idle control valve, but you could try looking for a good second hand one? Hopefully you won't need it though!
 

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I think it's your dump valve... i had the exact same problem in my '87 model Turbo. got one from a 9-5 aero and its all good (2nd hand one... pulled my old one apart and found a tear that went 1/2 way round the diaphram... could have been why my boost was low
 

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Just thought i'd suggest something else, as in my 9000 xs going through germany i had the same problem on the autobahns after i had filled the car with 100 or 98 ron (cant remember exactly, it was super thats all ) petrol, went back to bog standard 95 and it didnt stall any more. was pretty hairy tho
just another idea anyways
 

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Discussion Starter · #8 ·
Can anyone give me a general area to look for the bypass valve in a 1992 9000 CD? Im waiting for my haynes manual to come in and online repair sites for some reason always show where the 900 is located, but never were the 9000 is. Also, I had a radiator hose explode on me the other day which sprayed radiator fluid all over the right side of the engine compartment, there was nothing I could do but watch as a gallon and a half of radiator fluid sprayed everywhere. Im hoping I didnt short any components out, or im hoping that I just need to wait for them to dry out completely.
Also, I have been getting the blow off valve sound on occasion can a blow off valve fail intermitenly? Or if it works once is it always working? Thanks for all your help so far.
Any Help Is Greatly Appreciated,
Aaron Riesbeck

P.S. I live in the US so I go with our standard fuel 87
 

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First, just to check we're all on the same page, Blow off valve = bypass valve = dump valve!

If you look by the battery, you'll see a long 2.5" aluminium pipe that runs from the intercooler to the throttle body, with a few twists and turns.

About 1/3 of the way up this pipe, the dump valve is fitted. It's about 2" in dia, 2.5" deep, black plastic cylinder. The other big pipe from it goes to the inlet pipe that runs from the air filter box to the turbo. There should also be a small vacuum hose connected to it.

I think they can partially fail. They have a diaphragm in them, which can leak but not totally fail, although total failure will probably follow soon.
 

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my opinion on the fuel - get the highest octane fuel you can get. on a saab with APC and or DI, it is made for "98 RON or better" as the manual states (my '87 9000 turbo stated that.

Dump valve - mine had a split diaphram and only occasionally actually stalled... the revs would dip, but almost always recover. also i noticed boost seemed low. when i modified my apc, it didnt increse the boost at all, and my sppol up wasnt that great. now the boost is 16psi peak, as opposed to 10psi i was getting with leaking DV.
where abouts does your boost needle get to on your guage??
 
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