1993 850 2.0 20v 123 code and stalling

beardface · Post by **beardface** » 21 Dec 2014, 10:53

Hello, Bought a 1993 850 2.0 20v and it has the classic stalling/cutting out problem. Changed the fuel pump relay and thought the problem was cured but sure enough had got a few miles and was doing 50mph and it cut out and nearly caused an accident and I ended up leaving it at the side of the road and walked home.

I have read the 21 page monster thread on this problem and was wondering where to try next.

When it broke down earlier I pulled the code 123 from port 2, electrical short to battery. What could cause this? My first thought was engine coolant temp sensor or maf sensor, was hoping to get the car fixed for a long journey up country to vist family but the way its going it looks like its going to be a lonely one lol.

Post by **Ozark Lee** » 21 Dec 2014, 11:23

The 1-2-3 code from port A-2 indicates an ECT problem. What does the temperature gauge read? It should go to the 3:00 position and pretty much stay pegged there.

A bad ECT sensor will cause stalling but it will usually start again unless it is flooded.

...Lee

beardface · Post by **beardface** » 21 Dec 2014, 12:32

Cheers will give it a go.

Post by **Ozark Lee** » 21 Dec 2014, 13:48

I hope I'm not giving you bum information. As I thought about it you may have a Fenix ECU since this is a 2.0 but I think they just used the Fenix on some of the 10 valve engines. I have never actually seen a 10 valve or a 2.0 since they were never an option in the US. My depth of knowledge on those engines is nil.

The 1-2-3 code may mean something different if you have the Fenix system rather than the LH 3.2 system that was on the early 20 valve engines in the US.

...Lee

beardface · Post by **beardface** » 21 Dec 2014, 14:21

Thanks for the reply lee. I am going to replace the ect sensor anyway as its cheaper that a few other things on the list I have. Like replacing the fuel relay at least I can cross them both off the list. I also have a new fuel filter as the dealer let the car run dry and im sure thats dragged some crap through also. A new air filter and plugs wouldnt go amiss as fairly cheap, I usually change them everytime I get a new car. Might try a bit of cleaner on the maf sensor too.

All of that after fitting a new ect sensor first.

Thanks again, Ben.

Post by **JimBee** » 21 Dec 2014, 19:41

Just throwing out a couple of ideas on this one. I would rule out a fuel issue as, in my experience anyway, if fuel stops flowing for whatever reason the engine will usually sputter a bit before dying. Electrical issues are on/off for the ignition and are more likely to cause what you're describing. In that regard, check your ignition switch, fiddling with it (on a safe road or in your driveway : ) to determine if it might be worn and cutting out.

You might find some useful information on this site:
http://www.volvotips.com/index.php/850- ... ir-manual/

I think the repair manuals list test specs for sensors, though not sure if they include the '93's.

If you find this is really mysterious, check all your grounds. I have read there is one that causes most mysterious electrical issues and it's near the passengers side headlight. I have not located that one, but it's worth looking into if you can't solve it.

You can test an MAF with a multimeter.
Here are some links to check out:
https://www.google.com/search?q=volvo+8 ... o+test+MAF

Good luck.

beardface · Post by **beardface** » 22 Dec 2014, 04:26

Thanks jim, will look into it.