1.9 diesel woes - 16V/150 bhp

[paulf2012]

Hi - Please excuse this intrusion from a Saab owner - I've got the 1.9 16V diesel in my '06 Saab 9-3, which is the same Fiat (?) GM unit that many here have.

Recently cleaned the EGR (thanks to the excellent sticky on this forum), and also the MAP sensor (toothbrush + carb cleaner). EGR seems fine - starting OK, and engine warning light went out. The car runs mostly OK, but now have a slight judder or pulsing, when the engine is under load - e.g. slight hill, or accelerating out of a roundabout. This seems to start after 3 or 4 seconds under load, and lasts until the car reaches a steady speed. Engine speed doesn't seem to matter too much - starts at around 1500 rpm, but also evident at higher revs (2 - 2500 rpm). Rev count seems stable (i.e. not climbing/falling) when it is happening, but there is some additional noise. Hoofing it seems to stop it happening (not really a solution, well, not all the time...).

Long motorway run today - hoping it was still settling down/burning-out crud after unsticking the EGR, but still the same.

Wondering if I've damaged the MAP sensor when cleaning it - it was solid with carbon - like a small piece of coal. Can anyone advise if this would give the symptoms I'm seeing? Any other suggestions welcomed...

Thanks in advance/paul

[alcutler]

Hi - Please excuse this intrusion from a Saab owner - I've got the 1.9 16V diesel in my '06 Saab 9-3, which is the same Fiat (?) GM unit that many here have.

Recently cleaned the EGR (thanks to the excellent sticky on this forum), and also the MAP sensor (toothbrush + carb cleaner). EGR seems fine - starting OK, and engine warning light went out. The car runs mostly OK, but now have a slight judder or pulsing, when the engine is under load - e.g. slight hill, or accelerating out of a roundabout. This seems to start after 3 or 4 seconds under load, and lasts until the car reaches a steady speed. Engine speed doesn't seem to matter too much - starts at around 1500 rpm, but also evident at higher revs (2 - 2500 rpm). Rev count seems stable (i.e. not climbing/falling) when it is happening, but there is some additional noise. Hoofing it seems to stop it happening (not really a solution, well, not all the time...).

Long motorway run today - hoping it was still settling down/burning-out crud after unsticking the EGR, but still the same.

Wondering if I've damaged the MAP sensor when cleaning it - it was solid with carbon - like a small piece of coal. Can anyone advise if this would give the symptoms I'm seeing? Any other suggestions welcomed...

Thanks in advance/paul

Hi Paul, Welcome to the forum have you had a look at this - http://www.vectra-c.com/forum/showth...t=vacuum+hoses
Seems to be a quite common problem and easily sorted by replacing the small vacuum hoses at the front of the engine, Hope this helps. Some of the later posts will tell you what size piping you need and one or two Ebay contacts who can supply it. Did mine and it sorted the problem.

[dh.dti]

In addition to the vac tubes... Have you checked the swirl bar is in place & operating as it should.

[Big Sig]

Could also be the 3rd injector as they suffer from wiring issues thats easilly cured with a new harness thats fairly cheap.

[paulf2012]

Thanks to all - a few things to check at the w/e - and plenty of reading in the meantime about the hoses.

Had also wondered about the swirl bar - seen a couple of threads about this getting disconnected during EGR tinkering. Hoping it isn't that, as it seems others have struggled to get it hooked-up again...

[paulf2012]

Not much time at the w/e, but a quick check of the vac pipes didn't find any obvious perishing or splitting.

Saw that the swirl valve linkage was off, and lying on top of the inlet manifold - no idea it how long it has been like that. Cleaned it up, and re-fitted, but the cups on the bar are very worn, so not confident it'll stay on for long (have seen links to longer-term fixes for this, so may go down this route). The valves themselves could be turned (some resistance) by hand, so thankfully not seized solid. They now turn/open together, when the engine is running.

But (of course...) no difference to the pulsing/juddering under load problem.

The law of cause & effect makes me think it -must- be the boost/MAP sensor, as the problem appeared after cleaning this and the EGR. I'll get the sensor out again, and will go for a new one, if there is obvious damage.

While I was there, I drilled a 9mm hole in my EGR blanking plate, to reduce flow of exhaust crud into the inlet. Engine warning light came on, almost immediately, so it seems the Saab is more sensitive to any restriction to flow back into the inlet side. Now the proud owner of an EGR blanking plate, that doesn't blank anymore... Getting it mapped-out isn't a possibility at the moment (cost).

[merikiito]

Could also be the 3rd injector as they suffer from wiring issues thats easilly cured with a new harness thats fairly cheap.

I would say this is the cause and should be looked at first.
What colour are your injector plugs yellow or blue.
If they are yellow u need to at a minimum change injector no3 to blue using the kit avaialble for a few quid, best doing all 4 tho.

I dread to think how much money has been spent by owners trying to sort out the issues the 3rd injector plug causes when its a simple fix costing £12 ish