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94 850 engine problems and diagnostics

How much information is retained in the on-board diagnotics?

I've been getting repeated non-starts and some dies-while-driving during the recent spell of hot,humid weather up here in Toronto.

Chatting with the guys in Suter's Garage while making an appointment for my wife's S40 service, we think that it's probably that dad-blamed cam-sensor that causes simialr problems and has been talked about elsewhere.

So, I want to drop by the shop and have them do a reading for what's going on. MY question is how long will the information be retained (tiem and engine starts?)

And I may want to change the sensor myself and save the time in the shop. Just where is this sensor located and how hard is it to replace?

Thanks in advance!

Bruce Firm believer in 4x60 air conditioning until you start sticking to the seat and then it's MAX AC with FAN=4.....

Reply to
byrocat
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Is the engine error light on? If so an error is stored. If have also experienced the light going off again after some time and the error still being stored in the system.

Niels

Reply to
Niels Bengaard

If the light was on, then the code is stored for a long time, even if the light has gone off. A code is stored for 40 warmup cycles (start the car cold, drive for about 30+ minutes, turn car off) after the light has gone off, so you don't have to worry about running to the garage to get codes read. And with a 94 850, you can read codes with no special tools.

The cam sensor is on the back of the rear (exhaust) cam, and is quite easy to replace. However, from what I hear, the cam sensor will not cause stalling, just no start. Air mass meters seem to fail in this kind of intermittent manner, and the glitch can be long enough to stall the engine, but not long enough to set a code.

Reply to
Mike F

I don't remember seeing an engine error light, but will try to remember to check for it.

40 cycles? Hmmmm! Works out to 20 trips to work not counting trips. Since I'm aiming for a service in two weeks' time, I should be able to get a reading. Of course, every blow-up helps.

Will update when I get back from the shop.

Reply to
byrocat

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