The importance of an Air Filter

[nine-fiver]

Hi All,

Long time between posts.
However, since the 'dirty fuel incident' recently I have come across something worth a second look.
Sure, it is a no-brainer but after this weekend I am now convinced beyond doubt that the air filter element plays a more crucial role in the balance between economy and power than I originally thought.
The background briefly goes like this. Bit the bullet and put in a very young SH starter. Then it cranked like a new car. Fantastic!
But it would not fire. Once it did, after 30 seconds of cranking, it would catch....just...and be fine.
The car had a new fuel pump a while back. I had doubts as to the joiner pipe being split. Took the pickup out of the tank and replaced the submerged line with a more narrow ID pipe, fuel-rated of course. Then changed the fuel filter. Lots of metal particles floating about in the petrol, due to getting a batch of 98 from a recently re-furbed petrol station. Big mistake. Three tanks later and it is better but not great at this point. Without the air filter itself, the car was now an animal. Buckets of power. No control and no gentle modulation available. To the point where it was ridiculous. Full boost and very thirsty. Up to 16L/100km, which was a mild concern.
Decided to get a proper OEM SAAB air filter last week, (Made in Germany) and popped that in. The old one was black and needed changing.
Immediately the car was nice to drive. Had good modulation in heavy traffic, and best of all the economy went down to 10.9 L/100km in city stop-start driving. Even better on the highway too, 6.5L/100km. Just like it should be.
So. If your 9-5 is playing up...take the time to put in a new air filter and from there the Trionic will at least be seeing air flow values it expects. And the car will feel much more 'Saaby' than it used to.
Happy Motoring.

[sgould]

Way back, my father brought home the old works Minivan.  They were going to scrap it as it wouldn't run properly.  The garage they used said it needed a new engine. I was offered it for spares.  So I had a play.

It had one of the old type air filters.  A box of oily tangled wire.  It was virtually solid.  I washed it clean in a bowl of petrol.  After that the car ran fine....


.... Then Dad said that if that's all that was wrong, they would keep it at work!  So I never got to play with it.

It did highlight to me that "professional" garages were not the experts that they claimed to be.  From then on I trued to do as much as possible myself.  People criticised me for buying special tools, butthey were often cheaper than the labour charge in the garage.

[Audax]

It did highlight to me that "professional" garages were not the experts that they claimed to be.  From then on I trued to do as much as possible myself.  People criticised me for buying special tools, butthey were often cheaper than the labour charge in the garage.

I have major trust issues with pretty much all garages. My new tyres the other week all set to 32psi, also working in a specialists the number of cars we'd get in from other non-specialist garages where they'd really messed up the car when trying to get it running when it was actually a pretty simple fault. I've seen one where a garage had a non runner 9-3, they'd tried replacing the head gasket, lots of sensors by using guesswork, tried to stick an ecu on it and never (not even considered!) getting the fault codes read and eventually said it must be an immobiliser fault... When it first turned up we quickly checked it over and asked the apprentice what he thought was wrong with it,  he just walked into the workshop and picked up a test DI cassette, bolted it on the car and it started first time (he'd recognised the horrid burnt electronics smell). These guys had been in the trade over 30 years and had the car nearly 3 weeks. I've also seen cars with the timing chain way out, one where a (non-Saab) main dealer couldn't work out why the car was chucking plumes of oily smoke out the back due to a failed turbo, they reckoned it couldn't be the turbo as they'd "bypassed" it with a shonky bit of hose and jubilee clips on the inlet side.

Even then, I've also known the stuff that I've got wrong by missing out a basic test and it is quite easy to do, but when you get into that situation before you go down the route of tearing something to bits or replacing an expensive part you should just wander off and do something else for 30 minutes and have a think about it, very often when you come back you realise you didn't check the filter box, you didn't check the battery, you didn't check the hoses for a split etc. but it's the same way you don't get yourself into trouble by taking a break.