Saab Link Forums banner
1 - 4 of 4 Posts

·
Registered
Joined
·
103 Posts
Discussion Starter · #1 ·
2009 9-5 Aero auto trans 35K miles
stock no mods
When accelerating lightly no shudder
When accelerating moderately I am getting a shudder from the front end of the car that I can feel through the floorboards. Note this is not when the trans is shifting. I do not notice turbo gauge pressure varying - seems constant. It is not violent but I notice it and others have commented about it. I don't think anything is about to blow up on the car but it's more annoying than anything.

NO CEL

Researched and found out could be DI or plug issue. I pulled the plugs and found cylinder 1 gap was 0.6mm all others were fine. Changed gap on #1 to 1 mm.
According to service records plugs were changed at 30K service.
Swapped DI with a known good from my 9-3.
Shudder seemed slightly less but is still there.

Did some more research and found shudder could be the POS tires that the car came with (some cheap china @#[email protected]) or bent wheel or shot motor mounts or solenoid in trans or axles. Not sure it could be the mounts or axles because of the low miles on the car.

So not taking a shotgun approach on this, I'm going to swap the wheels with my BBS RK's from my 9-3 to see if it is the tires/wheels causing the shudder.

Anybody on here had similar issue with their 9-5?
 

·
Registered
Joined
·
103 Posts
Discussion Starter · #2 ·
Okay well here is what I've done so far:
Cleaned the MAF
Cleaned the Throttle Body
Installed new spark plugs (NGK PFR6H10)
Installed new DIC (Genuine Saab) <------Main culprit so far

The DIC has gotten rid of 90% of the shudder, but there is a bit left under acceleration.
Now the car tends to "undulate" when accelerating, almost surging and then receeding then surging all while the gas pedal is held steadily. Boost goes into red but then comes back to white when half throttle. When full throttle boost will stay at the bottom of the red section of the boost gauge.

I'm thinking boost control valve or bypass valve at this point. Or a bad throttle body or fuel pump.

Anyone? Bueller, Bueller???
 

·
Registered
Joined
·
53 Posts
its an 09 so its not exactly old and worn out.. if the DI (which is an item known to fail) fixed the issue 90% its not exactly ...likely.. that in such a young car other parts will have already failed...possible of course but not likely.. id go back over everything you touched and make sure its 100% correctly together nothing loose or connected wrongly.... make sure a vac line didn't come loose in a spot you didn't see while you were working....

make sure the intake pipe at the top of the TB is extremely tight and the large hose at the end of it- make sure everything is SUPER tight
 

·
Registered
Joined
·
103 Posts
Discussion Starter · #4 ·
More work done to chase this problem

After replacing the DI Cassette, I moved on to replacing the Mass Airflow Sensor (55557008 ) that I got from Eeuroparts for $160.
Car was definitely running smoother than before but now it would idle roughly when warm and still some stuttering when accelerating.

Did some more research and discovered the MAP sensor could be the culprit. Ordered 55563262 MAP sensor and when looking underneath the plastic intake manifold cover discovered that the white plastic valve on the oil trap line was broken off inside the crankcase side of the valve. Ordered part 5955927.

MAP sensor install was easy. The plastic white valve that is on the oil trap line is another story. As the valve is glued onto the hose on the crankcase side, you have to replace the entire hose and valve and this is a pain in the ass to do.

The MAP sensor definitely made the car a lot smoother but it was still a little rough. Was hoping this was due to the broken valve on the crank vent hose.

After playing around with trying to install the crank vent hose 5955927, I finally cut up the old one with tin snips but marked with blue painters tape the route the hose took snaking through the intake manifold and such down to the oil catch box. This got most of it out of the way so I could try and release the snap fitting with my hands on the hose that was attached to the oil catch box.

Still couldn't get the hose off the oil catch box underneath the throttle body and intake manifold (could only get one hand in there from below the car, and not enough strength with thumb and pointer finger to release the fitting).

Here's what I did: Removed the intake manifold bracket to get that out of the way. Tested all kinds of tools on the new hose to see what I could get to release the plastic snap fitting from the hose that was attached to the oil catch box. I could rotate the old piece now and get it into position to slide a 15/16" open end wrench that released the snap fitting and allowed me to pull of the last bit of the hose.

Snaked the new hose from below the car through the intake manifold as the path was marked by the blue painter tape. Took some patience to make sure I didn't break the valve off the new hose. Got it up top snapped into the clamp next to the valve cover, went below and snapped the other end to the oil catch box. Replaced intake manifold support bracket and secured the other end to the throttle body hose with a plastic tie.

Result: Car is now running a lot smoother, more powerful and running very strong....the way Aero's are supposed to be.

I'm still getting some vibration but I don't think this is due to the engine. I also discovered the serpentine belt was missing about 1/16" of one edge of the belt, so that will be my next project.
 
1 - 4 of 4 Posts
Top