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.....

 

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

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

 

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.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

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.