Volvo 940SE Auto Est. (1991) Question

"Stephen Hobbs" schreef in bericht news:4KIGb.487$ snipped-for-privacy@newsfep1-win.server.ntli.net...

Steve, if it is the lamda symbol ( /\) then the cat or the sensor may be on its way out; or both. If it is not lit steadily, is there a pattern? Like, it lits only when accellarating? IIRC the lamp comes up when emissions are out of specs, e.g. when the mixture was too rich.

Hans

Hans, Thanks for the reply, I have'nt noticed any pattern so far, probably because I have not driven it enough yet! We went on a 110ml round trip the other day and I noticed it came on once whilst on the motorway. It also came on recently while driving around the city centre. I can't say it has only come on when cold or hot either. Is it worth changing the sensor, or should I "let it develop" so to speak?

Steve

Really you need to extract codes from the computer whilst the light is on. If its only intermittent and the engine and mpg performance remain normal, that will be alittle tricky to do. It would be wise however to go around the engine bay and unplug, check for corossion and replug all the multiplugs you can see. The one for the o2 sensor is abit tricky to reach though.

Tim..

I thought it stored up to 3 codes, meaning that you can look for them at your leisure. Use the brickboard 700/900 faq to see what the codes mean.

Stuart.

Car is 740, year 1990 station wagon: Motor (2.3 L) stalls when driving. Can happen when motor is warm or cold, driving slow or fast. "Check enging" light comes on. Starts up again without any problem. This has happened about 5-6 times during the last month. Seems to be some intermittent problem. Took it to dealer. The check engine light is still on. Dealer says that when computer is checked, states that engine light came on because of load sensor signal or speed (speedometer? ) input signal. Cannot repair it because signals are all OK now. Cold be problem w computer, load sensor, some loose wire, or whatever. Told me to come back when it cannot be started, because then they can diagnose it and see what is wrong. Has anyone experienced similar problem???? Cannot take car far from home, because never knows when it will act up again.

I would suspect the hall sensor, don't recall whether it's in the distributor or at the flywheel with that year though. Also wouldn't hurt to resolder the fuel pump relay.

Great dealer. I will assume your car has LH 2.4 fuel injection (B230F). I will also assume that you're talking about the engine speed sensor, which will cause the engine to stall if it fails. It also commonly fails intermittently, which seems to be your problem. On my brother's 1990 740 Turbo, he got a check engine light and the code for engine speed sensor, without stalling, without even noticing any problem, several times. We put in a new sensor (which is supposed to be improved from the original), and the check engine light has not come on since. This part is mounted on a bracket at the rear of the engine, on the top of the bell housing.

Was it "No load signal from fuel injection system" (ignition code

1-4-4)? I have a 1990 740 GLE which had been stalling out and giving that code. It had been going on for several months, getting progressively more frequent.

I replaced the fuel injection relay (a known problem with that model) about 6 months ago. It has not stalled since and no error codes stored. I have no idea why it was giving that error code for the failure, but it appears to have been the correct fix.

The part is about $35 (US) and it's an easy job. Instructions can be found at brickboard.com on the 7xx FAQ, or from a search of the archives of this newsgroup.