2002 v70 codes galore!!!! HELP

[mart1471]

Hi folks, Recently aquired a 2002 manual v70 2.4 non turbo, however heres where the fun starts!!

Engine management and warning triangle are lit, codes :

Iat sensor ckt intermittant
crankshaft position sensor a ckt range
H02 sensor bank 1 sensor 1 heater circuit high
maf or vaf A circuit high input

surely not all of these sensors could have gone down at once? Any suggestions welcome as i need my puppy carrier back!!

Thanks

[Clan]

I would clear them all and see which comes back first if any ... 2 of them could well have been caused by someone taking the air mass meter plug off whilst removing air filter box with ignition on .
However it is likely you will need a new Lambda sensor .

[mart1471]

Hi there

a friend did remove the afm plug whilst the ignition was on dohhh

all have been cleared and have come back though??

Would the lambda sensor cause it to struggle whilst cold and only rev to 3500rpm?

Thanks

[Baldwithabeard]

It could be the AFM , one or both Lambda sensors or and I hope it's not, the ETM.

[mart1471]

Thanks for the replies

Is there a way to test the afm, lambda sensor or crank sensor with a multimeter?

Iv done this before with my old bmw and found the problem??

Thanks

[Unreal master tech]

Sounds like there could be two faults the lambda probe heating element will be causing one fault for sure but I reckon it could be an etm fault as it creates problems with air flow and upsets the mar readings as a result but try a doing one thing at a time rather than fix it all in one go it makes financial sense as the lambda probe won't be effecting the cars running as the car will be running open loop when the heating element is used so focus on the other fault first

[mart1471]

Hi again

once the cars running it runs beautifully, flys up to 3500rpm, i was led to believe a failing etm would cause low idling and hesitation?

It just takes 3 turns to start in the morning and starts first time when warm?

Full volvo service history etc

Could the etm failing allow it to drive so nicely?

Thanks

[Unreal master tech]

It could as if the cars ECM can't see the signals it needs from the etm it puts it into limp mode which can differ but it could mean a limit to engine revs which could be your issue here according to the chaps on the site the fix for the etm that is available is not too dear and at least your etm should be easy enough to remove with it not being a turbo model?!

[RUTV70]

Wouldn't a 2002 model be POST-Magnetti Marelli ETM.?..thought they improved with another system after that debacle.?..which were supposed to be far more reliable/different design etc. (Bosch.?)
Are there failings there too then.?.

Neil

[Unreal master tech]

The etms were stopped in 2003-4 from memory it then changed to an actuator(it also had no software for the unit it was a slave unit from which it was controlled by the ECM)