[namb]

Hi
While since I've posted anything so hello everyone!
My son has inherited my 2008 Aero Estate (2.3T Turbo Edition)
Approaching 100k miles and its developed a strange engine knocking/shudder/missing/vibration fault

The car:
Fully serviced
Crankshaft sensor changed as we suspected that may be the problem
Just changed coil pack
Symptom only appear when car is hot
Car starts on the key no problem
Uses a little bit of oil but that's expected
I've told him to take it to the defuncted saab dealership in Oxford who are really helpful and take a mechanic out as the fault can be replicated easily - it does it on every journey
As soon as the car is put under load the fault appears
If he backs off the throttle, the fault disappears
Car then runs ok until under load and the fault reappears!
The vibration can be so violent it can trip the Ecu into a fault mode and needs to be reset.

So, a strange problems so wondered if anyone on the forum has experienced similar problems or has any ideas?
Best regards
Mark

 

[Mike Brennan]

If not a vacuum leak, which I suspect it is, is the new DIC a saab unit or and aftermarket. The latter are often bad. He might try disconnecting the MAF and see if it changes the problem. He really needs to get the code read, that is really the first step.

 

[aerojon]

As mike say get the code/s read..

 

[namb]

Coil pack is a new SAAB part. He managed to get a good discount on the unit. Vacuum leak? Mmmm. Where would that be and why would it only occur when hot? MAF was changed about 3 months ago so unlikely to be that. Apparently the code only occurs when the shudder is extreme and it's only occurred once. The dealer reset it. There was a suspicion it might be a massive vibration from a drive shaft but that's still an open question. There is some minor sloppiness in the drive train but the symptom only occurs when hot, never when cold?
We're basically grasping at straws now which is frustrating. It's still a great car and my son is losing patience and is considering something else. We think one last chance with the ex SAAB dealership and if it can't be diagnosed, it's goodbye 95!! :-(