Acceleration/Throttle Issue

I have a 2005 Saab 9-3 Linear Tiptonic. It has a little over 171,000 on it and so far over the last year that I’ve owned it everything is been great! I’ve had a couple of parts replaced lately, but my major issue at the moment is my acceleration. When in park or neutral it revs fine. It will go all the way into the red if need be. Once I put it in drive I can’t get it over 2,000RPM. The car will drive fine and then once I get off the highway it starts acting up and has a hard time accelerating. It was an occasional problem but now it’s happening every day. Once I get it moving it drives fine and takes off but as soon as I hit a red light or a stop sign it takes forever just to get going again. If anyone can help me with this issue it would be greatly appreciated! The CEL is throwing a code for a turbo bypass valve (p1110). Thank you :(

When you ask a question like this it really helps to mention if you have a 4 or 6 cylinder engine with a stick or automatic transmission. The problem with reading into the extended code set with a generic reader is that it doesn't tell you everything you need to know and your P1110 could be a -1, 2, 3, or 4. So with a couple of guesses at which engine you have, which ECM you have and that you have an auto transmission because you mentioned park and neutral that you probably have a bad boost valve or vacuum hose. You could just as easily have a bad intake air temp sensor or cable connection.

From reading your post for trouble as described, I suspect that Tiptronic is a typo and that you have a Trionic 8 ECM, that you probably have a 2.0t because they are very common and that your waste gate is stuck full open and that your cause is bad vacuum or bad valve.

Digger, I agree with your conclusions; the 9-3 Linear wasn't sold with anything but a 4 cylinder engine as far as I know and the mention of "Park" and "Neutral" suggests to me that the car is an automatic. I am sure Matty will correct me if I am wrong.

The bypass valve is a known weak area but worse is the valve that, supposedly, controls it.
Locate the bypass valve, often incorrectly referred to as a "dump" valve, and trace the vacuum hose.
If the hose goes to a small box on the bulkhead, follow it from there to the inlet manifold.
I would suggest you replace the hose with 3mm silicon hose and go directly from the manifold to the valve bypassing the box on the bulkhead.
While the hose is disconnected, attach a short length to the bypass valve and suck on it, if you get a continuous flow of air into your mouth the diaphragm has split and you need a new valve. If the valve moves, you should be able to hear it, all is well.

Induction leaks have a serious effect on the fuel/air mixture because, either un-metered air is getting to the cylinders and causing a weak mixture or, pressurised air is leaking and giving an over rich mixture both of which conditions are undesirable.

The 2005 9-3 was manufactured by GM and only came in a 4cyl. GeoffR, the hose was snapped from the bypass valve. I really appreciate your help on that one. It’s been driving me crazy the last 2 weeks I ordered the bypass valve and new hoses today. Hopefully everything works out once I put the new pets in. Thank you again!

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Originally Posted by MattyWeil

The 2005 9-3 was manufactured by GM and only came in a 4cyl. GeoffR, the hose was snapped from the bypass valve. I really appreciate your help on that one. It’s been driving me crazy the last 2 weeks I ordered the bypass valve and new hoses today. Hopefully everything works out once I put the new pets in. Thank you again!

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Glad it was that easy to find.
I have had six Saabs with engines similar to yours and the faults are common to most of them. My first one was a 1986/7 9000 that had done long journeys and the vacuum hoses were basically cooked. Over a number of months I replaced all of them and in the process discovered what effect each had on how the car performed. After the second one I replaced the hoses as soon as I got a car and never had a repeat of the problems I had with that 9000.

I would recommend that every owner of a Saab made between 1986 and 2010 replace the vacuum hoses, it costs under $20 and will either resolve or prevent many annoying issues.

okay so i got the new turbo air bypass valve and had it put in. the car ran great for all of maybe 5 hours and then the check engine light came back on sending out the same code as before. we ran a diagnostic on the vehicle and it comes back to the same turbo air bypass valve. im waiting on new vacuum lines and hoses now. i don't know if my mechanic didn't clean out the lines before he hooked it up or what, but the weather by me has gotten much warmer and the car is running worse and worse. does anyone happen to have any suggestions? at this point im losing my mind...

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Originally Posted by MattyWeil

okay so i got the new turbo air bypass valve and had it put in. the car ran great for all of maybe 5 hours and then the check engine light came back on sending out the same code as before. we ran a diagnostic on the vehicle and it comes back to the same turbo air bypass valve. im waiting on new vacuum lines and hoses now. i don't know if my mechanic didn't clean out the lines before he hooked it up or what, but the weather by me has gotten much warmer and the car is running worse and worse. does anyone happen to have any suggestions? at this point i'm losing my mind...

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Sounds reasonable, probably the vacuum hoses have deteriorated, one does not clean them out simply replace them. There is a small valve on the bulkhead, follow the vacuum line from the bypass valve back to find it. This is what is actually calling the fault code. This valve is supposed to smooth the action of the bypass valve but in practice serves no useful purpose and it can be bypassed by running the vacuum line direct to the manifold. Replace the vacuum hoses first though.

I have a 2007 9-3 (4 cyl turbo) which is having a series of throttle problems. Fault codes have led to replacement of first engine control module and then a month later the throttle body. Driving it back from shop I punched the accelerator from a dead stop and engine light activated, engine sputtered (missed), and acceleration was very slow (took over a minute to get to 60 mph). My mechanics have checked bypass valve (don't feel this would cause problem) and are now check vacuum hoses (also don't believe this will cause problem). The problem now seems limited to when accelerator pedal is floored. My mechanics are Saab specialists and seem stumped. I am getting more than a bit worried here. Any suggestions?