couple of issues with my 156 2.0 Tspark

[deadtom]

Evening all,

I took a chance on a 2002 156 sportwagon 2.0 from fleabay the other day, and im already starting to worry that this was a mistake...

the engine cooling fans come on as soon as i start the engine, and the engine temperature gauge in the car isnt doing anything; it just sits at minimum.

also its totally gutless below around 3k rpm or above 4.5k rpm in any gear, and only adequately powerfull between those points.

the car doesnt seem to make any untoward noises, doesnt smell or feel like its overheating and coolant level is correct (at least in the header tank in the engine bay it is). it also had a new radiator fitted not long ago.

im reasonably mechanically minded, but i dont know much about electronics and cooling systems, would the fans and temp gauge work from the same sensor, or do they each have their own?


any ideas?

Thanks,

Tom

[crostonian]

Try a new air flow sensor would be my first port of call.

[deadtom]

i assume that wont do anything about the cooling system, just the lack of grunt?

[robsco]

That's correct, there's a good chance the MAF will be at fault. You might want to try a new thermostat too for the engine temp, that's if the gauge itself isn't faulty.

[OldEngineer]

This could simply be a failed connection to the temperature sender in the thermostat housing. The whole fan system is worked of the ECU (which switches on the negative side, ie, the positive is a straight connection). The fans have a high speed cicuit and a low speed cicuit. The low speed is just fed through a resistor mounted on the radiator (so it feels the temperature of the water and offers less resistance when hotter)

But here's the interesting thing; the manual says, if you want to test the fans, remove the sender connection and note if they start up. This is because the sender feeds an input to the ECU and without it the system thinks it's hot.

[deadtom]

where might i find the connector in question?

and am I likely to do any damage running the car as it is? i generally do less than 50 miles a week, so not really heavy usage

[Altosportivo]

Had similar story with a friend with a 2.0 TS Spider. Fans on constantly and temperature gauge showing nothing. He changed the thermostat the other week. Gauge now reading normal and fans kicking in as they should.

On power the MAF may well be the issue. Disconnect it and give it a run and see how it feels. If your power is back time for a new MAF.

[Paul S4]

Not sure if this is OK to post on here...but 156.net or alfaowner are very good at problem solving; I have found them invaluable if you own an Alfa...as there are no English workshop manuals...!

[Geoffcapes]

Got exactly the same on my 156. Bought a new thermostat from Euro Car Parts. 27 quid. Tell em you're trade. should sort the fans.
Sounds like the Maf for the sluggishness.

[deadtom]

well, it died.

it started with a ticking sort of noise at about half throttle (it seemed to be related to throttle position rather than engine speed), then it lost power and wouldnt even maintain speed (about 50mph at the time), then the oil light came on.

now what?

the car is still sat by the side of the road. only thing i can think of is to check if its run out of oil, and if so top it up and see if it goes again?

failing that, get it towed i suppose.

anything else anyone can think of?

[alfa pint]

It won't have run out of oil just like that - you'll have noticed / smelled it somewhere and seen it on your driveway. And if it had run out of oil, then the engine's now seized and putting more oil in it won't revive it.

It really does sound like the MAF. Common-ish fault. Have a look on the alfaowner.com technical website. You should be able to unplug it, which should allow the engine to restart and you can at least drive it to a garage to have it replaced.

The thermostat is another common fault, but one you could swap over yourself as it's not that hard. However, even it was stuck open, the engine should be heating up to some degree, so you should see something appearing on the gauge. Might well be an electrical fault that's part of the thermostat, so worth changing anyway.

Good luck!

[deadtom]

alfa pint said:

useful stuff

I wrote that last reply in a bit of a hurry as i had to go try and retrieve the car, so i shall expand on what happened to it.

like you said, it wouldnt have lost all its oil just like that and i did check under the car and in the engine bay for any oil and didnt find any. at least, not excessive amounts, just the usual you would expect. and also like you said if it had conked out due to lack of oil it would be seized solid, but even after it lost all power and the oil light came on it was still idling ok, so it certainly hadnt run completely dry.

I went back to it today and found that it was low on oil, so i added a couple of litres of oil and fired it up again. it started and idled fine, oil light wasnt on and all seemed ok, but then as i pulled out onto the road it was definitely down on power and the ticking noise started again. and so it continued for the whole 3 mile journey back to my mates house, with the ticking noise then being accompanied by a slightly heavier sounding knocking noise which happens across the whole rev range and gets worse with higher engine speeds (unlike the 'tick' which seems to only happen with a certain amount of pressure on the throttle) and the oil light is flickerign again.

so thats where i am at the moment. at idle its ok, but anything above that it rattles like a skeleton in a biscuit tin. the dipstick shows plenty of oil, but the oil light on the dash is flickering. i checked under the bonnet to see if there was anything obviously loose, but it all looks ok and the noise appears to be coming from under thet rocker cover.

what do?

Edited by deadtom on Monday 30th January 12:25

[deadtom]

i dont know much about these engines, would they have hydraulic tappets/lifters/followers/whatever they're called?

if the oil wasnt getting around the engine properly, could this result in horrible noises from under the rocker cover, and the low oil light coming on?

[yardman]

I'm new to Alfa having just bought a 147 2.0 TS but went through a lot of buyer's guides recently.

I've read a bit about how the cam variator can suffering if run low on oil - upshot: requires replacement but also means new cambelt, tensioner, the lot. There is a fair bit out there on google about it. Seems to match the symptoms you describe.

Some suggest trying an engine flush then thicker oil (10w60) first before shelling out on the above.

[deadtom]

oh dear

how much would a new variator and related gubbins be to replace?

and would it have run low enough on oil to do that much damage without the low oil light even coming on?

[alfa pint]

New variator and cambelt is a standard Alfa change and is usually about £400 all in. I'm not sure about the damage caused by lack of oil as it's not happened to me.

It is definitely definitely definitely worth looking on alfaowner.com and doing a search in the 156 technical forums for more specific, expert advice.

[deadtom]

does the cam belt have to be done at the same time as the variator? I ask ebcause the cam belt was done only a few thousand miles ago

EDIT: just looked back at some old bills and it looks like the belt, tensioners, pulleys and variator were done 12000 miles ago.

is it likely to have happened again so soon?

[alfa pint]

If the belt has stretched at all if there is any damage then it will. The belt itself doesn't cost that much, it's the variators and the labour in getting at the gubbins that makes it expensive.

[deadtom]

have signed up to alfaowner, so will see what they have to say.

-sigh-

remind me why i thought it was a good idea to buy a 10 year old alfa?

[robsco]

It sounds to me like you've ran the car low on oil, it has broken, you have topped it up too late and then driven it further while it develops a louder knocking from previous damage related to being low on oil.

To then make a sarcastic comment about 10 year old Alfas is a little silly, bearing in mind that any engine on the planet will be seriously damaged being ran without sufficient lubrication.

The MAF won't be related here as it wouldn't trigger an oil light. Cam variator is a possibility but I would doubt it, in relation to what you've told us. Best of luck with the fix.