It turns out my car might be a little bit special

Here’s a story that put a smile on my face last week.

I’ve been having ongoing problems with my 1985 Saab 900 Aero. I would drive a long and then all of a sudden the car would struggle, like it was starved of fuel. I spoke to my mechanic on the phone, describing the issue as it happened and he suggested it might be the fuel pump. If I could get it started again I was to go and fill up and then try to get it home. The fuel system in the 900 runs on a two-pot reservoir type arrangement (my description, not his) and filling it up completely should help. Which it did.

Thinking we’d discovered the problem, and said mechanic not having actually seen the car, we made plans to put a new fuel pump in. Which we did.

$300 dollars and a few kilomoters later, it died again.

So Matt the Saabologist/fudgepacker came over and diagnosed a faulty airflow sensor thingy (again, my description, not his). When the car dies, I’m supposed to lift the hood and tap on the little metal box with the black plastic top, and a few minutes later it goes again. And so it does. It’s died once or twice since and just like Matt said, a few knocks on the black box seems to do the trick.

The problem now, is that it’s happening with increasing frequency.

I brought the car into my regular mechanic’s workshop to give him a look at it and get suggestions. Being an intermittent fault, however, it followed the usual rule that binds all intermittent fauls and it refused to happen while Steve had the car.

But Steve did notice something unusual, which is where the backstory ends, and where the real story starts…..

Many of your Saabs will have a ‘check engine’ light that comes on when you turn the key. The little computer does its thing and once everything checks out to be OK, the light goes off.

My 1985 Saab 900 is supposed to have that light as well but a quick turn of the key revealed that no light would come on. Steve figured that the bulb must have expired, or had been removed. A closer inspection of the check lights on the dash, however, revealed that there wasn’t a “Check engine” light there at all.

This threw Steve into the far reaches of his memory. The car was supposed to have the light, but didn’t. And there was only one previous instance where he’s seen that situation.

Steve has been working on Saabs for a long time. A very long time. He was working on them well before 1985 when the first 16valve Saab 900s arrived in Australia.

The only other time he’d seen this situation was with a car the dealership had as a press vehicle. There were a small number of pre-release 900s with the 16 valve engine brought to Australia so that the press corps could have their drives and writeups ready prior to the model’s official release.

These press cars were duly driven and some stayed in dealerships for further tests and were supposed to eventually be gathered together and sent back to Sweden to be crushed. Some of the dealers, however, were a little tricky and ended up selling these pre-release cars as well as the stock they eventually received. Hey, 900s were hot property back then and manual stock control systems weren’t quite as timely in their reporting, I guess.

The only other time Steve saw this ‘check engine’ light missing was in one of these pre-production cars, a black one that was displayed and later sold at Kingsway Motors here in Hobart. And what’s more, neither that black car nor my silver car were/are fitted with an o2 sensor.

Of course, this is all anecdotal and from the memories of one person. But it’s a person who’s been working on them for a very long time. I don’t know if I’d ever be able to get verification from Saab as to whether or not this is actually the case, but it’s a good story nonetheless.

——

A few other stories he told me about the old days:

One dealer in Perth got hold of a car that had been used in a Saab Performance Team exhibition. It had had the diff locked off so as to be able to do the driving-on-two-wheels stunt. The dealer hadn’t realised that the modifications would make the car very unruly on the road, and sold it to a customer who was later to be most dissatisfied with his new Saab.

——

Another mainland dealer got hold of a NG900 that had been used as a test vehicle and had tried to wind back the odomoter. Being a digital unit, he hooked up the equivalent of Tech II from the time but the device would only let him wind the clock forward. He figured he’d keep winding it forward until it clocked over after 999,999 and then set the desired mileage. Only problem was that the digital system keeps it at 999,999. It doesn’t clock over.

Perhaps even more stupid was his enquiry as to why it wouldn’t clock over – a red flag if ever I heard of one. Subsequent enquiries uncovered his intended actions and it wasn’t merely a wrist-slap that resulted – his dealership was quite rightly revoked.

11 thoughts on “It turns out my car might be a little bit special

  1. Sounds like a mystery to be resolved! The C900 air mass meters can be problematic once they’re a bit long in the tooth. The only real cure is to replace it unless there is something obvious fouling it.

    Vive la C900!!

  2. Curious – how much does a Mass Airflow (MAF) sensor for an ’85 cost? Those things have always been expensive, but it sure does sound like the problem.

    Maybe Matt could hook up a meter to the sensor output terminal for you and see if output goes to zero (or lower than normal airflow) when the part fails? I assume there is no scan tool data-stream on that car, but that would achieve the same effect.

    We used to do that on older vehicles to pinpoint intermittent problems – which was always fun.

  3. They’re expensive, Ted, which is why Steve wanted to look it over first and make sure. A new one will set me back around $700 or so.

    Looks like I’m going to have keep tapping on that black box for a little while yet.

  4. Swade: we can always stop by while you’re here and pick up a rebuilt air mass meter. It might cost you less to buy one in the States and take it home w/ you.

    I’ve replaced mine before and they’re not cheap, but they’re not $700 here either! :-o

    A new (not rebuilt) one from thepartsbin.com goes for $250 but you have to trade-in your old one ($35 core fee). Eeuroparts.com is selling rebuilt ones for around $200 but you get $30 back for trading them your old one. Let me know ahead of time if you want to do this as I might have to order it to have it in time for you to be here later this week. I can inquire if there’s a local storefront I can buy an air mass meter from, as my indie has a source, I believe.

  5. I believe that no 1985 900 Aero (nor any other variant of 900) had an o2 sensor as Australia was still on leaded petrol then. It wasn,t until 1986 that we got unleaded fuel, and thus we had o2 sensors fitted in the cars. I also believe (but don’t quote me) that non-o2 sensor cars had no need for a check engine light… this was for cars running unleaded petrol only.

    Might be worth doing some research into that angle too?

    Damn nice car tho swadey… it was fun to drive when you were here in melbourne!

    sab

  6. Thanks sab, Hadn’t thought of that. It runds on unleaded with no additives or anything, but it doesn’t have the unleaded fuel filler gate.

  7. yep they will run fine on unleaded with no additives at all as the turbo 900s (and n/a too i believe) have hardened valves, and have so since 1979. No need for upper end lubrication :)

    sab

  8. Hey Swade, when I had my 85 900 Turbo some years back, the same air mass meter was failing as well. My Saab mechanic (some 20+ years with Saab) said to go grab one from a wrecker. As long as that filament and connector is intact you should be fine. I picked one up at a wrecker for $30 and the car ran fine after that – saving me some $250 for a new one.

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