My girlfriend has been getting codes on her `92 940 turbo recently, and said that it's been running "gravelly"
I popped the hood and found two codes stored.
2-3-2 (too trim or lean at idle) and
1-3-1

So for the 2-3-2 signal, i've done all sorts of research online and it looks like it may be as easy (or hard) as a new o2 sensor.

For the 1-3-1 signal, I have no idea.
Chilton's manual says "Engine speed signal from DI system absent on starting"
volvospeed.com says "RPM sensor signal missing"
k-jet.org has a ton of diagnostics for 1-3-1 codes, but no info on what to do for any of the diagnostic results.

Are Chiltons and volvospeed saying the same this? What's a DI system? Where is the RPM Sensor signal?

Thanks in advance!

 

I've been looking into this more - and have found the car has two oxygen sensors. My local parts shop quoted me $100 for one of them and $150 for the other. Do these typically need to be replaced in pairs? Or is there some way to diagnose which is sending bad information?

Still havent learned anything about the 1-3-1 code.. It's driving me crazy!

 

O2 sensors have a service life. If you don't know how old they are, replace them both. They will pay for themselves in 25k miles or less with reduced fuel consumption.

Regards, Andrew.

 

Thanks for the info on the o2's typhoon - will replace them both.

Update on the 131 code - for any one searching for this thread in the future, the 131 is the rpm sensor. I've been searching high and low for this - all over the internet, volvo forums, etc, and calling local part shops.

TURNS OUT - that this is also called the crankshaft position sensor - and it looks like it's wicked easy to replace. Here's some info.

http://www.brickboard.com/RWD/index....903&show_all=2