Back again with a question. Call me stupid, but I jump started my 850 yesterday with the positive and negative terminals all connected. Didn't read the book first so didn't realise I should have connected the negative cable to the engine lifter or some other earth as far away from the battery as possible. After the car started, smoke started to come up from behind/under the exhaust manifold on the far side (furthest from the battery) and progressed to the near side of the exhaust manifold before I managed to get the jumper leads off. Ceased instantly once the jumper leads were disconnected. Car has driven beautifully all day yesterday after this. A warning light I had been trying to get rid of has gone out but all other dash lights seem ok. The warning light comes on when the key is turned as per normal with all the other lights. I have been hunting round trying to find out what the smoke might mean with no luck so far. The only repercussion I can find from doing what I did is that the battery may have exploded. Lucky for me that did not occur and the smoke was nowhere near the battery.
Would any of you have an idea what I may have done and what the consequences might be.
As always, I appreciate all your help.
Hello again Tracy.
Not much down there but the oxygen sensor and maybe an earth cable and neither should have been affected really. Am not an electric wizard by any means! It is a good idea to replace the earth cables if you can, not strictly necessary but there are threads on Mathews Volvo Site or TB about the benefits.
Your warning light before,which was it?
Make sure the alternator is charging properly and you can do the simple mod to it to make it charge better,look.it up.
If the oxygen sensor is bung, the car will default to a setting in the ecu of running rich cos it doesn't know what's going on fuel wise without the oxygen (O2) sensor. Mine is old and toast so.I use more fuel.Ebay have Bosch ones cheap if you search.Second hand is waste of time unless you know how to test and clean them. The main lead from battery to alternator and the earth from battery are easy enough to get to. Cable can be had cheap,ask an auto electrician how much to make up the leads and you do the work? Or at last resort, Supercheap have the bits.
You must post some pictures of your beasts!!
Thanks for the info Snoopy,
The flat battery was user error... mine again. Having a good run here eh? I left the boot slightly ajar when I removed a couple of paintings the other night and the boot light flattened the battery. So, no mystery there. Have now turned the boot light off so hopefully will stop myself from doing that again!
The light that is no longer on was the Fault in the engine electronic system light. We have a broken connector on the Engine Camshaft Position Sensor which has been wired together and is working. Car won't start without it. Thought this might have been the reason for the light and then couldn't get it to go away after wiring it. Will be replacing this Sensor in the future and didn't worry about it for now.
I have just checked my fuel consumption (with minimal driving after the jump so this may vary if I have stuffed the O2 sensor). I am getting 9litres per 100klms. Not too bad I would have thought. I do country driving - very little urban. Could be better I suppose. Let me know what you think.
My partner is convinced the smoke was electrical. It started too quickly for it to be oil or other substance to burn off the exhaust. Also stopping instantly when the jumper leads were removed. He wonders whether the O2 sensor might have got a kick in the guts which may have turned the warning light off. We looked at the 2 earth leads and they are on top - not where the smoke came from.
I have now sold the 240. After I fixed the knock sensor connector she ran like a bird. Sad to see her go actually but can't keep them all.
Thanks for your input,
Oil on the earth cable at the back of thee engine burning off? Worth replacing that earth at this age anyhow.
Thanks for that. Will replace the earth. It was a bit instant though. Nothing had time to heat up.
Flattened battery probably cleared the codes for the sensor you somewhat fixed BTW. Hence those lights going.
Cables get mighty hot real quick if they are a bit corroded at the connectors or generally corroded internally and the oil may have just finished burning? None left?
Good call @egads!
Worth doing all the cables you can with larger diameter stuff,even buy from welding supply shop it will be cheaper.
Saying that I must do mine, typical ey,full of advice,not done it myself!!
Ohh, 9l/100 is ok country for a turbo, I would expect better for the NA I think you have,is it 10 or 20 valve? Les
FWIW, I always jump start straight positive to negative from battery to battery, it should not have caused an issues...