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Saab turbo stutter

The car: 2003 Saab 9-5 Linear turbo - manual transmission - 192k miles

The problem:
When turbo boost pressure gets close to the red under acceleration - either with high rpm: 3rd gear/50mph and max throttle OR low rpm: 6th gear / 45mph and max throttle - engine cuts out abruptly, and ‘stutters’ until you ease off the gas.
Check engine light is triggered if it isn’t already on, which it usually is. O

Please help. This same question has been asked on several other car/Saab boards, but I still haven’t found anyone who has solved it.

“Check engine light is triggered if it isn’t already on, which it usually is.”
First step is to post the codes you are getting. Then we might have some ideas on the cause.

Yes @Purebred cut right to the chase… We as well as you, need those engine codes…Your engine/vehicle is trying to tell you something. Listen to what it has to say and we can help guide you from there.

Symptom wise it sounds like it could be an ignition timing problem and or a fueling problem…Since they sort of mimic each other in a general fashion, we really cant tell you further at this time.

The codes man…we need the codes.

From your other post on the same issue :

The diagnosis:
Trusted mechanic has replaced ignition coil (twice to be sure), swapped spark plugs with cylinder 4 (still sees issue in cyl 5) and now thinks it is either a bad fuel injector (from what I hear these are very reliable) or a major ‘valve’ issue which would entail a presumably very expensive head rebuild.

Well those theories need to be figured out… Like I mentioned earlier…it could be ignition related or fuel related problem…because under boost those two items fluctuate rapidly and are both very important. If anything gets out of whack the engine software shuts things down…

You need to have a mechanic sort out which item is the root cause… its not that difficult for a skilled tech to determine… It needs to be sorted out, there no way round it.

The OP of this thread responded to your question there, if you haven’t noticed already, and gave his solution to the problem.