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Sudden Stalling - (Update) 850 1993

Well, I haven't managed to solve anything. Today, its running great. Couldn't get the symptoms to appear. Yesterday it started running crappy intermittently, so I swapped out the fuel pump relay with a spare. It still had the same issues, so I know the relay is fine.

I read the diagnostic codes:

A-1 was 3-1-3 A fault code for the PNP switch. I replaced that sucker about a month ago. I was really starting to act up.

A-2 1-1-1
A-3 4-4-3 ABS Pump motor, electrical or mechanical fault
A-6 2-1-4 Engine speed (RPM) sensor signal missing sporadically
A-7 1-1-1

I cleared all the codes and when for a drive. Car ran great, no rough running or almost stalling. Then I rechecked the codes and everything read 1-1-1

Its possible the issues arise only after the engine has been running for a while. Right now there's nothing to troubleshoot, but I have some important driving on my schedule and I have to get this cleared up.

Klaus, if you're there, you mentioned "if the pressure is positive, it is time to clean the PCV...)

Any instructions as to how to clean the PCV? ... Can a clogged breather system produce these intermittent symptoms?

Thanks.

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Sudden Stalling - (Update) 850 1993

A-3 4-4-3 ABS Pump motor, electrical or mechanical fault
A-6 2-1-4 Engine speed (RPM) sensor signal missing sporadically

If the ABS light refuses to turn off after 20mph, check the electrical wiring. The ABS pump motor never fails mechanically.

Your best bet to poor running is the RPM sensor. I would check the wiring for the cam position sensor. Make sure it does not get close to any spark plug wires or the coil wire. Also check the connector for those 2 wires, plastic tends to degrade over the years.

The PCV has nothing to do with engine performance. First, clean out the flame trap, located next to the throttle body. If there is still a plastic screen in there, throw it in the garbage - there has NEVER been a backfire through the flame trap.

The problem with a clogged oil separator is that as the crank pressure increases, so does the likelihood of a seal (cam or RMS) being blown out. In order to replace the oil separator you must remove the intake manifold. Long job, lots of bending over, and for the 1993, hard to find parts. Normally, the oil separator doesn't get clogged, but the passages from there back into the block do get clogged. Also the hoses tend to get very brittle from the heat.

I believe your car has EGR, which makes it more interesting getting the manifold off.
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Keeping it running is better than buying new







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