Is it the rpm sensor or the cam location sensor on my 94 850

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byrocat

Standing beside the driver front wheel, I look at the engine block.
Just to the right and above the distributor is a round cover held on
with two screws, with a single wire that goes towards the distributor.

Is this the cam location sensor that you get a heat failure with (car
stalls and then will not start until it all cools off)?

My copy of Haynes has the illustration (5.47 on page 2B-6) That has the
cam sensor (14) line pointing down toards the distributor, while
there's a line pointing at where the sensor is supposed to be that says
that its the rpm sensor (16).

To top things off, I don't have a link to thae "brick" website that
deals with repairs so I can figure out what I need to do.

Also, has anyone had any experience with a used cam sensor replacing
the one that's heat-sensitive. I'm looking at about 250 Canadian for a
new one. (OUCH! -- <:-o) !)
 
byrocat said:
Standing beside the driver front wheel, I look at the engine block.
Just to the right and above the distributor is a round cover held on
with two screws, with a single wire that goes towards the distributor.

Is this the cam location sensor that you get a heat failure with (car
stalls and then will not start until it all cools off)?

My copy of Haynes has the illustration (5.47 on page 2B-6) That has the
cam sensor (14) line pointing down toards the distributor, while
there's a line pointing at where the sensor is supposed to be that says
that its the rpm sensor (16).

To top things off, I don't have a link to thae "brick" website that
deals with repairs so I can figure out what I need to do.

Also, has anyone had any experience with a used cam sensor replacing
the one that's heat-sensitive. I'm looking at about 250 Canadian for a
new one. (OUCH! -- <:-o) !)


Yes, this its the Cam Position Sensor (CPS) located on the exhaust cam
(dissy on inlet cam).

On any car with Motronic or Fenix management (not LH 3.2) i.e. those with a
single ECU for engine control, failure of the CPS will cause failure to
start.

Be careful to distinguish from a faulty crank angle sensor on the
bellhousing as this will also cause a no-start.

Arm yourself with a can of freeze spray or brake cleaner, and when it next
dies, spray one sensor at a time to cool it off and attempt a restart. See
which one needs to be cool for the engine to start.

Tim..
 
JUzt in case someone is giving this a quick scan.I've got two distinct
non-run behaviors that seem to be possible the same item.

If the car has been sitting in direct sunlight for a couple hours, I
can make a trip and get out to do some shopping. The restart for the
trip home results in a almost-run burble and then everything lights up
and I now have to go for a can of pop and then more shopping until
everythign cools down.

The second is when I'm in traffic and at an idle, burble and then dead.
Sometimes, an immediate restart works and sometimes I'm there for a
while.

However, lugging around a can of comressed air and blasting the sensor
plate and area around and giving things a retry is a good idea.

Of course, Murphy's Laws of Testing will apply: when ready for a
failure to diagnose the reason for the failure, the failure will not
occur.
 
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